Title of Invention	COMPOSITION FOR GENERATION OF HYDROGEN BY THERMAL DECOMPOSITION OF AMMONIA BORANE (AB) USING SILICON NANOPARTICLES AS CATALYST.
Abstract	The invention relates to the method for hydrogen generation from solid hydrogen storage compositions. This is achieved by thermal decomposition of ammonia borane (AB) in the presence of silicon nanoparticles. With addition of silicon nanoparticles, decomposition of AB was found to be less exothermic and the second step of decomposition was found to be slightly endothermic suggesting hydride formation. Induction period was absent with silicon nanoparticles and also increase in the amount of gas released was found.

Title of Invention

COMPOSITION FOR GENERATION OF HYDROGEN BY THERMAL DECOMPOSITION OF AMMONIA BORANE (AB) USING SILICON NANOPARTICLES AS CATALYST.

Abstract

The invention relates to the method for hydrogen generation from solid hydrogen storage compositions. This is achieved by thermal decomposition of ammonia borane (AB) in the presence of silicon nanoparticles. With addition of silicon nanoparticles, decomposition of AB was found to be less exothermic and the second step of decomposition was found to be slightly endothermic suggesting hydride formation. Induction period was absent with silicon nanoparticles and also increase in the amount of gas released was found.

Full Text	FORM 2 THE PATENTS ACT 1970 (Act 39 of 70) COMPLETE SPECIFICATION (See Section 10) TITLE OF INVENTION: Composition and Method of Generation of Hydrogen by Thermal Decomposition of Ammonia Borane (AB) using Silicon Nanoparticles as Catalyst APPLICANT(S): Name: Indian Institute of Technology (HT), Bombay Nationality: Indian University Address: Indian Institute of Technology (HT), Bombay, Powai, Mumbai - 400076 The following specification particularly describes the invention and the manner in which it is to be performed. TITLE: Composition and Method of Generation of Hydrogen by Thermal Decomposition of Ammonia Borane (AB) using Silicon Nanoparticles as Catalyst. FIELD OF INVENTION: The invention relates to a method for hydrogen generation from solid hydrogen storage compositions. This is achieved by thermal decomposition of ammonia borane (AB) in presence of silicon nanoparticles. Further the invention relates to elimination of induction period and improvement in kinetics , while increasing the amount of release of hydrogen. BACKGROUND OF INVENTION: Transition from petroleum based energy economy to hydrogen based energy economy is a major challenge today [Brown et al. 2006]. Particularly, for a fuel cell vehicle, storing sufficient amount of hydrogen on board is a troublesome issue. Other than the conventional compressed gaseous storage and storing in the form of liquid, chemical hydrogen storage in the form of solid compounds is considered a much desirable option [Hausdorf et al. 2008]. As compared to metal hydrides, chemical hydrides are composed of lighter elements and therefore offer higher gravimetric hydrogen densities. In chemical hydrides class, ammonia borane (AB, NH3BH3) is the most desirable hydrogen storage component for transportation applications [Bowden et al. 2008]. AB has highest hydrogen content per mass (19.6 wt %) as compared to any other hydrogen storage materials. It is non-toxic, stable material and can be easily and safely handled under normal atmospheric conditions [Ramchandran et al, 2007]. Further, it is a white crystalline solid at room temperature [Shore et al. 1955]. AB is a widely studied material for its decomposition by thermal route as well as hydrolysis. When heated, AB decomposes in three steps at the temperatures of about 100 °C, 140 °C and above 1000 °C [Frueh et al. 2011] respectively, for releasing one mole equivalent of hydrogen in each step. The first ever decomposition study of AB was reported in 1978 by Hu et al. [Hu et al. 1978], in which the decomposition was studied by thermo gravimetric analysis (TGA), differential thermal analysis (DTA) and thermomanometry. The solid residue was found to be BNH2.1 after heating to 170 °C and BNH(0.8 - 1.2) after heating to 200 °C. Borazine and other undesirable products were observed to be formed along with polyamino borane [Sit et al. 1987] when decomposition steps were studied by pyrolysis and products were analyzed by IR spectroscopy and deduced by mass balance calculations. Further, in another prior art reduction in the decomposition enthalpy was observed along with lowering of activation barrier and suppression of borazine when AB was loaded in mesoporous silica SBA-15 [Gutowska et al. 2005]. Thermal decomposition of AB in carbon cryogel depicted improvement in kinetics of hydrogen release as compared to neat AB [Sepehri et al., 2007]. Further, in another prior art suppression of borazine and other toxic byproducts was found. In another study on carbon-AB nanocomposites [Sepehri et al. 2008] it was shown that decomposition temperature of AB decreases with decrease in the carbon cryogel pore size. Decrease in the induction period and reduction in the activation energy has been reported when AB was destabilized using LiH [Kang et al. 2008]. Also addition of LiH caused reduction in exothermicity suggesting possibility of regeneration. Addition of diammoniate of diborane (DADB) to neat AB was found to be useful in reducing the induction period [Heldebrant et al. 2008] and it was further suggested that during decomposition of AB, formation of DADB is a key step. AB when added with nanoscale boron nitride (BN) [Neiner et al. 2009] by ball milling resulted in decrease in the dehydrogenation temperature, reduced ammonia formation and reduced exothermicity. Dehydrogenation properties further improved with increase in the nano-BN concentration. In another study [Neiner et al. 2010] it was suggested that formation of borazine can be avoided by isothermal heating upto 150 °C. AB catalyzed with nanosized cobalt and nanosized nickel was found to release hydrogen at a temperature as low as 59 °C [He et al. 2009]. Also reduction in the activation energy was observed. Use of alkaline earth metal hydrides i.e. magnesium hydride and calcium hydride [Zhang et al. 2010, Int. J. Hyd. Energy] and alkaline metal hydrides i.e. lithium hydride and sodium hydride [Zhang et al. 2010, J Phys Chem] was found useful in altering the thermodynamics and kinetics of AB decomposition. Several approaches, including use of metal organic frameworks either by mixing [Li et al. 2010] or by chemical incorporation [Li et al. 2010, Eur. Chem. J.], use of magnesium metal powder [Luo et al. 2010, J. Am. Chem. Soc], ionic liquids [Basu et al. 2011], zeolite-X and K-chabazite [Gangal et al. 2011] have been reported to improve dehydrogenation properties of AB either in terms of suppressing borazine formation, improving kinetics and thermodynamics or decreasing temperature of dehydrogenation. In general it can be stated that additives alter decomposition properties of AB to a great extent. Interaction of silicon and hydrogen is widely studied as hydrogen helps passivation of the defects in silicon and improves its properties. Hydrogenation of silicon is done to improve its opto-electric properties. Hydrogenation of polycrystalline silicon thin films can reduce grain boundary defects and improve the solar cell efficiency [Honda S. et al., 2006]. Hydrogen is readily chemisorbed on Si dangling bonds [Le T. T. Tuyen et al., 2001]. Kale et al. have shown experimentally that hydrogen can be physisorbed as well as chemisorbed on silicon nanoparticles [Kale et al., 2011]. It is reported in the literature that H-H bond length in the hydrogen molecule is about 0.764 A while N-H bond length in AB molecule is 1.024 A and B-H bond length in AB molecule is 1.218 A [Lee S. M. et al. 2009]. Thus if silicon can disrupt H-H bond in hydrogen molecule we think that it can also assist disruption of N-H and B-H bonds in ammonia borane. The silica increases the rate of hydrogen release from the ammonia borane by two orders of magnitude compared with the release of hydrogen from ammonia borane alone. Furthermore, heating the hybrid material above 3 7 OK to release the second equivalent of hydrogen gives rise to very little borazine, a volatile impurity that needs to be minimised to avoid poisoning Polymer Electrolyte Membrane Fuel cell (PEMFC). The studies so cited above shows there is problem to generate hydrogen at low temperature without improvement in kinetics of reactions. Also rate of generating hydrogen is slow with undesirable side products. US patent 7,316,788 and US patent 7963116 describes materials for storage and release of bulk quantities of hydrogen and methods of making and using same. In these patents, a way to deposit ammonia borane within the porous channels of mesoporous silica has been disclosed. The drawback of the mesoporous scaffold is its weight. The team is now studying how the scaffold improves hydrogen release to develop a hybrid material that does not significantly add to the weight or volume of the ammonia borane systems. Accordingly, there is need to generate hydrogen at much faster rate of reaction with improved kinetics and low induction period. Also there is need to suppress undesired products. The SUMMARY OF THE INVENTION: Ammonia borane found to be the desired material for the hydrogen generating material when additives are added. The present invention solves the problem of generating hydrogen in much simpler way with reduction in induction period and improvements in kinetics. The present invention discloses the composition of hydrogen generating material using catalyst and the method to synthesize this composition. Further, the present invention, thermal decomposition of neat AB and silicon nanoparticles doped AB under transient temperature conditions in a TGDTA system as well as under isothermal conditions in a constant volume standard Sievert's type apparatus is disclosed. A long induction period of 125 minutes was observed in case of neat AB decomposing at 90°C and gravimetric hydrogen storage capacity of neat AB was estimated to be 4.2wt%. With addition of silicon nanopartides to AB by ball milling, this gravimetric storage capacity at 90°C increased to 5.4 wt% without any induction period. At temperature of 110°C, 30 minutes induction period was observed in case of neat AB and for ABSi the induction period was absent. At 135°C and 150°C induction period was not observed in both the samples and also the decomposition curves depicted same nature. The wt% released was found to increase with addition of silicon nanopartides for decomposition at 90°C, 110°C and 150°C, however at 135°C it was negligibly less as compared to AB. In TGA decomposition steps in case of AB and ABSi were found to be almost same with a little higher mass loss observed in case of ABSi as compared to AB. In DTA exothermic peak corresponding to second mass loss step of ABSi was absent and instead the reaction was found to be slightly endothermic suggesting gas solid reaction forming hydride. This indicates the possibility of regeneration of AB from the residues of decomposition. XRD and FTIR studies showed presence of silicon in the residues of decomposition indicating that silicon is acting as a catalyst. Also HRTEM confirmed nanosizing of silicon suggesting successful synthesis of silicon nanoparticles by ball milling. This is the first report of using silicon nanopartides as catalyst in decomposition of AB. Ball milling of silicon nanopartides with AB resulted in reduction of induction period and increase in the amount of gas released. Besides, the addition of silicon nanoparticles suppressed the foaming and swelling phenomenon as observed in case of neat AB thermolysis. OBJECTS OF THE INVENTION: It is an object of the present invention to provide a composition consisting of hydrogen storage material such as ammonia borane in particular and Silicon Nanoparticles which acts as a decomposition catalyst for the decomposition of hydrogen storage material. It is another object of invention to use the said silicon nanoparticles as catalyst in lowering the decomposition temperature of ammonia borane along with reduction in the induction period and improvement in kinetics, It is yet another object of invention is to synthesis the said composition of hydrogen storage material such as ammonium borane and silicon nanoparticles which in turn are made by a simple technique such as ball milling of porous silicon thin films in a most cost effective way and thus have the potential to serve in the immediate application of the invention that can release hydrogen at the conditions suitable for Polymer Electrolyte Membrane Fuel cell (PEMFC). BRIEF DESCRIPTION OF THE DRAWINGS: A complete understanding of the invention may be obtained by reference to the accompanying drawings when considered in conjunction with the following detailed description, in which: Figure 1(a) is Transient Temperature decomposition behaviour of AB and ABSi examined by TGA. Figure 1(b) is Transient Temperature decomposition behaviour of AB and ABSi examined by DTA. Figure 2(a) is Isothermal decomposition of AB and ABSi at 90°C. Figure 2(b) is Isothermal decomposition of AB and ABSi at 110°C. Figure 2(c) is Isothermal decomposition of AB and ABSi at 135°C. Figure 2(d) is Isothermal decomposition of AB and ABSi at 150°C. Figure 3 is HRTEM of silicon nanoparticles, Inset: 4-5 run sized Si nanoparticles exhibiting differently oriented lattice fringes. Figure 4 is XRD pattern of AB and ABSi and decomposition products of ABSi. Figure 5a is FTIR spectra ofì¥Á 5@ ð ¿ ²u bjbjÏ2Ï2 “ X X ²m ÿÿ ÿÿ ÿÿ ˆ 6 6 6 6 6 6 6 : þ þ þ þ \ and at (e) 150°C. DETAILED DESCRIPTION OF THE INVENTION: In an embodiment of the present invention, a composition is provided consisting of hydrogen storage material such as ammonia borane in particular and inorganic nanoparticles such as silicon nanoparticles which acts as a decomposition catalyst for the decomposition of hydrogen storage material. The term "ammonia boranes" includes compounds containing N—H and B—H bonds such as compounds represented by formula NHxBHy, wherein x and y are independently an integer from 1 to 4 and do not have to be the same, including NH3BH3 In one embodiment of the present invention, thermal decomposition of neat AB and silicon nanoparticles doped AB under transient temperature conditions in a TGDTA system as well as under isothermal conditions in a constant volume standard Sievert's type apparatus is studied. The term inorganic nanoparticles catalyst includes but are not limited to, members selected from the group of porous materials, such as, silica, silicon dioxide, mesoporous silica and more particularly porous silicon thin films. The silicon nanoparticles catalyst can be effectively and efficiently dispersed in a hydrogen storage material comprising a complex hydride using a grinding technique. Non-limiting examples of grinding techniques include ball milling. The ball mill, a type of grinder, is a device used to grind materials like ores, chemicals, ceramics and paints. The ball mill may rotate around a horizontal axis, a vertical axis, or an axis inclined between the horizontal and the vertical, partially filled with the material to be ground in addition to the grinding medium. An internal cascading effect reduces the reactants to a fine powder during the process. The grinding medium can be ceramic balls, or stainless steel balls coated with a ceramic. An exemplary ceramic is tungsten carbide. (It should be emphasized that other types of grinding media are also possible). The amount and size of balls, as well as size of the vessel, are selected to provide effective grinding of insoluble solids during the reaction. Planetary ball mills such as PULVERISETTE 6 can grind mixture particles to as small as nanometer dimensions, enormously increasing surface area and reaction rates. Catalyst synthesis: Silicon nanoparticles were prepared by ball milling of porous silicon films. Freestanding porous silicon films were obtained by Two Step Separation (TSS) process. Ball milling was done in a Fritsch pulverisette-6 ball mill in 80 ml stainless steel (SS) bowl with 3 mm tungsten carbide (TC) ball set for 24 hours. Homogenised mixing of hydride storage material and catalyst: Ammonia Borane (AB) 97 % pure was obtained from Sigma-Aldrich and was used as received. In one of the embodiment, ammonia borane is provided in molar excess relative to the silicon nanoparticles. As an exemplary embodiment of composition comprising an ammonia borane, and the silicon catalyst, combined in a molar ratio of about 10 to about 1 moles respectively. The mass ratio of AB to silicon nanoparticles was kept 10:1. The mixture was ball milled for one hour using 10 mm SS ball set in 80 ml SS bowl with a milling cycle of 10 minutes milling followed by 10 minutes pause. Purpose of ball milling here was just to homogenize the mixture and no intention was there to reduce the particle size of material. This mixture of AB and silicon nanoparticles is referred as ABSi henceforth. Decomposition of ABSi: Decomposition were performed on neat AB and on AB mixed with silicon nanoparticles. Isothermal decomposition was carried out in an indigenous standard Sievert's type apparatus and transient temperature experiments were performed in a Perkin Elmer TG/DTA system under flowing argon having flow rate of 50 ml/min from room temperature to 250°C. Isothermal decomposition was studied under vacuum at 90°C, 110°C, 135°C and 150°C. On heating, the sample decomposes and releases gases which can be observed by change in the pressure. This change in the pressure of the apparatus was used to estimate the amount of gas released with the help of van der Waals equation for real gases. Decomposition of ABSi sample initiated immediately as the heating started. Endothermic melting event is observed at about 108°C which is delayed by about 8°C as compared to AB. In contrast to AB where three exothermic events were noticed after melting, only one exothermic event is observed following an endothermic melting event in case of ABSi. The weight loss steps almost coincide with that of AB except the initial weight loss observed in ABSi which is absent in case of AB. Also decomposition of ABSi is significantly less exothermic as compared to AB. Particularly, only the first decomposition step is found to be exothermic in case of ABSi and no exothermic events were found corresponding to the second major weight loss step but in contrast the reaction was observed to be slightly endothermic. The effect of silicon nanoparticles addition on thermal decomposition of AB, further volumetric measurements were carried out on AB and ABSi at constant temperature of 90 °C, 110°C, 135°C and 150°C in vacuum. Isothermal decomposition behaviour of AB and ABSi is compared in figure 2. The sigmoid nature of decomposition curve of AB at 90°C in figure 2a is similar to that reported in literature where the three stages namely induction, nucleation and growth are observed. Unlike AB, where induction period is about 125 minutes in ABSi although the decomposition curve is sigmoid in nature, no induction period is observed for 90oC decomposition. Absence of induction period is desirable property for practical hydrogen storage applications. In addition to the reduction in induction period the amount of gas released is significantly high for ABSi when compared with AB. It is found that at 90°C ABSi releases 5.4wt% whereas AB releases only 4.2 wt%. Also the time required to release 4.2 wt% in case of AB is about 350 minutes whereas the same amount is released in about 200 minutes in ABSi. Decomposition reaction is initially slow in case of ABSi till it releases about 0.7 wt% in about 100 minutes. Then the reaction accelerates for the next 100 minutes releasing a total of about 4.2 wt% in 200 minutes and finally the reaction decelerates. Absence of induction period in ABSi is in well agreement with the TGA curve in figure la where weight loss starts immediately as the heating starts. The wt% in case of ABSi is calculated by taking into account the weight of silicon nanoparticles. Similar isothermal measurements were performed at 110°C, 135°C and 150°C and the results are presented in figure 2b, 2c and 2d respectively. It is observed that at 110°C decomposition is much faster as compared to that at 90°C. Induction period of 30 minutes is observed for AB while for ABSi there is no induction period observed which is as expected. When the sample temperature and the time coordinate were carefully examined it was found that the induction period of 30 minutes observed at 110°C decomposition is the time required by the sample to attain the temperature of about 100°C. After the temperature of about 100°C is reached the sample decomposes vigorously releasing large quantity of gas in a short time and then the reaction curve becomes flat taking long time to stabilize. At 110°C AB releases about 7 wt% and takes a total time of about 400 minutes for this gas release. The same amount is released in about 100 minutes by ABSi sample. Also the total amount released by ABSi is about 7.9 wt% which is quite high as compared to AB and it is released in about 225 minutes only. Except for the little induction period in case of AB and difference in the amount of gas released, the nature of curve is same for both AB and ABSi at 110°C. At 135°C, both AB and ABSi show almost same decomposition curve. The amount of gas released is negligibly higher for AB as compared to ABSi. Both curves show rapid gas release initially for about 50 minutes where about 7.5 wt% is released and then a flat region till the end of reaction. Total amount released is about 10 wt% for both AB and ABSi which is quite higher as compared to that released at 90°C and 110°C. Decomposition curves at 150°C are similar to that at 135°C. Here too induction period is absent. AB shows faster gas release as compared to ABSi initially upto about 50 minutes after which the decomposition curve for AB is seen to stabilize releasing 12 wt% in about 300 minutes. Initial 10 wt% is released in only 25 minutes in case of AB while for the same amount to be released it takes about 50 minutes for ABSi. But the total amount released by ABSi is about 13 wt% which is quite high as compared to AB. Also the total time needed for releasing that wt% is only 150 minutes which is significantly less as compared to AB. Characterisation of Materials: Materials were characterized by X-ray diffractometry (XRD) analysis using Philips Xray Diffractometer using Cu Ka radiation having wavelength 1.54 A within the 20 range of 10° to 60°. A Fourier Transform Infra Red (FTIR) spectrum of the materials was recorded using Jasco FT/IR-6100A system in the range of 400 cm'1 to 4000 cm"1. XRD and FTIR measurements were carried out on neat AB, ABSi and on the spent ABSi sample after thermal decomposition. Nanosizing of silicon was confirmed by HRTEM. Figure 1 shows the thermal decomposition behaviour of AB and ABSi examined by TG/DTA. For AB, an endothermic melting peak is observed at about 100 °C. Following the melting event three exothermic events were noticed with the peaks observed at approximately 118°C, 149°C and 173°C. These exothermic events correspond to the decomposition steps and probably forming polymeric amidoboranes and polymeric imidoboranes respectively Silicon nanoparticles were examined by HRTEM to estimate the average particle size. Particle size calculated from HRTEM image of the as prepared Si nanoparticles powder shown in figure 3 exhibits a range of 4 to 20 nm. Figure 3 HRTEM of silicon nanoparticles, Inset: 4-5 nm sized Si nanoparticles exhibiting differently oriented lattice fringes. Porosity of the films was determined using gravimetric method and was found to be 29%. Figure 4 shows XRD pattern for AB, ABSi and the decomposition products collected after isothermal decomposition of ABSi. The XRD pattern of AB shows sharp peaks exhibiting crystalline nature and well matches with JCPDS reference no: 01-074- 0894 suggesting tetragonal structure of AB. XRD pattern of ABSi shows peaks corresponding to AB as well as silicon. This clearly indicates that no solid phase reaction occurs between AB and silicon. AB peaks can be seen clearly whereas silicon peaks are not very sharp. This may be due to low loading or poor crystallinity of silicon. But a careful observation of the XRD pattern confirms the existence of both AB and silicon separately. After decomposition at 90°C XRD peaks corresponding to AB disappeared. XRD pattern of solid residue obtained after decomposition of ABSi at 90°C referred as ABSi_90C is shown in figure 4. Two broad peaks at 2 Theta values nf 23 6° and 48.5° were observed suggesting formation of amorphous decomposition species. Absence of silicon peaks indicated participation of silicon nanoparticles in the reaction. Carefully matching the peaks and profile with JCPDS reference patterns suggested formation of a polymeric compound Borane Amide with chemical formula (BH2NH2)5 and the JCPDS reference no. 00-019-0418. Similarly XRD pattern of residue after decomposition at 110°C, 135°C and 150°C did not show any sharp peaks however the 15 OX pattern well matched with silicon (JCPDS reference no.: 00-040-0932) indicating that silicon nanoparticles worked as catalyst and remained unaffected in decomposition process. Figure 5a and 5b show FTIR transmittance spectra of AB and ABSi whereas figure 6 shows FTIR spectra of ABSi and its decomposition products. It can be seen from figure 5a that after milling AB with silicon nanoparticles N-H band near 1600cm"1 has disappeared while that near 1400cm"1 is slightly shifted. Also the B-N stretching band near 782cm'1 is affected. As seen in figure 5b, the B-H stretching frequencies in the range of 2100cm"1 to 2400cm"1 are also affected and the effect is seen in terms of broadening of the transmittance peaks. Similar effect is observed for N-H bands in the range of 3100cm'1 and 3300cm'1. Except for these few changes no appreciable change is observed in the FTIR spectra of AB and ABSi. Surprisingly no peaks were observed corresponding to silicon which may be due to small amount of silicon present in ABSi and because no solid phase reaction occurs during ball milling. FTIR spectra of ABSi decomposition residue after decomposition at 90°C} 110°C, 135°C and 150°C are shown in figure 6. As the temperature of decomposition increases from 90°C to 150°C N-H and B-H bands get broadened and finally disappear. No bands corresponding to silicon or Si-H are found in the FTIR spectra of decomposition products indicating that the silicon nanoparticles act as catalyst and do not form any chemical bond. This is in well agreement with the XRD results which also suggested that silicon nanoparticles act as catalyst only. B-N bands in the range 700cm'1 to 900cm"' are seen weakened but still exist thus ruling out the possibility of disruption of B-N bonds and ammonia formation. We claim: 1. A composition for generating hydrogen comprising, a. a solid state hydrogen storage material.; and b. an inorganic nanoparticle catalyst, wherein the amount of catalyst relative to the ammonia-borane complex is 5 wt% - 15 wt%. 2. The composition of claim 1, wherein the solid state hydrogen storage material comprises a chemical hydride. 3. The composition of claim 2, wherein the chemical hydride is ammonia borane. 4. The composition according to claim 3, wherein the chemical hydride is an ammonia borane selected from the group consisting of compounds of formula NHxBHy, wherein each of x and y is any integer from 1 to 4 and do not have to be the same. 5. The composition of claim 1, wherein the inorganic nanoparticle catalyst comprises Silicone. 6. The composition of claim 5, wherein the said Silicone consists of porous silicon films. 7. The composition of claim 5, wherein the size of said inorganic nanoparticle catalyst is in the range of 4 nm to 25 nm. 8. A method for making a hydrogen generating composition, comprising the steps of: (a) ball milling an inorganic catalyst for 24 hours providing nanoparticles of size 4 nm to 25 nm; (b) mixing ammonia borane (AB) and the said inorganic nanoparticle catalyst by ball milling thereby providing homogenised mixture; (c) thermally initiating the said homogenised mixture to generate hydrogen. 9. The method of claim 9, further comprising heating the mixture to a temperature range between 90°C to 150°C. 10. The method of claim 10, wherein weight percentage of hydrogen generated is 5 to 13 for said temperature range. 11. A system of hydrogen generation comprising: a composition having a solid state hydrogen storage material; and inorganic nanoparticle catalyst, the said composition when homogenised and then thermally decomposed, generate bulk quantities of hydrogen with reduction in the induction period of decomposition of said composition at temperature range between 90°C to 150°C and with improvement in kinetics than said solid state- hydrogen storage material when thermally decomposed in absence of said inorganic nanoparticle catalyst.

Full Text

FORM 2
THE PATENTS ACT 1970
(Act 39 of 70)
COMPLETE SPECIFICATION
(See Section 10)
TITLE OF INVENTION:
Composition and Method of Generation of Hydrogen by Thermal Decomposition of Ammonia Borane (AB) using Silicon Nanoparticles as Catalyst
APPLICANT(S):
Name: Indian Institute of Technology (HT), Bombay
Nationality: Indian University
Address: Indian Institute of Technology (HT), Bombay, Powai,
Mumbai - 400076
The following specification particularly describes the invention and the manner in which it is to be performed.

TITLE:
Composition and Method of Generation of Hydrogen by Thermal
Decomposition of Ammonia Borane (AB) using Silicon Nanoparticles as
Catalyst.
FIELD OF INVENTION:
The invention relates to a method for hydrogen generation from solid hydrogen storage compositions. This is achieved by thermal decomposition of ammonia borane (AB) in presence of silicon nanoparticles. Further the invention relates to elimination of induction period and improvement in kinetics , while increasing the amount of release of hydrogen.
BACKGROUND OF INVENTION:
Transition from petroleum based energy economy to hydrogen based energy economy is a major challenge today [Brown et al. 2006]. Particularly, for a fuel cell vehicle, storing sufficient amount of hydrogen on board is a troublesome issue. Other than the conventional compressed gaseous storage and storing in the form of liquid, chemical hydrogen storage in the form of solid compounds is considered a much desirable option [Hausdorf et al. 2008]. As compared to metal hydrides, chemical hydrides are composed of lighter elements and therefore offer higher gravimetric hydrogen densities. In chemical hydrides class, ammonia borane (AB, NH3BH3) is the most desirable hydrogen storage component for transportation applications [Bowden et al. 2008]. AB has highest hydrogen content per mass (19.6 wt %) as compared to any other hydrogen storage materials. It is non-toxic, stable material and can be easily and safely handled under normal atmospheric conditions [Ramchandran et al, 2007]. Further, it is a white crystalline solid at room temperature [Shore et al. 1955]. AB is a widely studied material for its decomposition by thermal route as well as hydrolysis.

When heated, AB decomposes in three steps at the temperatures of about 100 °C, 140 °C and above 1000 °C [Frueh et al. 2011] respectively, for releasing one mole equivalent of hydrogen in each step. The first ever decomposition study of AB was reported in 1978 by Hu et al. [Hu et al. 1978], in which the decomposition was studied by thermo gravimetric analysis (TGA), differential thermal analysis (DTA) and thermomanometry. The solid residue was found to be BNH2.1 after heating to 170 °C and BNH(0.8 - 1.2) after heating to 200 °C. Borazine and other undesirable products were observed to be formed along with polyamino borane [Sit et al. 1987] when decomposition steps were studied by pyrolysis and products were analyzed by IR spectroscopy and deduced by mass balance calculations. Further, in another prior art reduction in the decomposition enthalpy was observed along with lowering of activation barrier and suppression of borazine when AB was loaded in mesoporous silica SBA-15 [Gutowska et al. 2005].
Thermal decomposition of AB in carbon cryogel depicted improvement in kinetics of hydrogen release as compared to neat AB [Sepehri et al., 2007]. Further, in another prior art suppression of borazine and other toxic byproducts was found. In another study on carbon-AB nanocomposites [Sepehri et al. 2008] it was shown that decomposition temperature of AB decreases with decrease in the carbon cryogel pore size. Decrease in the induction period and reduction in the activation energy has been reported when AB was destabilized using LiH [Kang et al. 2008]. Also addition of LiH caused reduction in exothermicity suggesting possibility of regeneration. Addition of diammoniate of diborane (DADB) to neat AB was found to be useful in reducing the induction period [Heldebrant et al. 2008] and it was further suggested that during decomposition of AB, formation of DADB is a key step. AB when added with nanoscale boron nitride (BN) [Neiner et al. 2009] by ball milling resulted in decrease in the dehydrogenation temperature, reduced ammonia formation and reduced exothermicity. Dehydrogenation properties further improved with increase in the nano-BN concentration. In another study [Neiner et al. 2010] it was suggested that formation of borazine can be avoided by isothermal heating upto 150 °C. AB

catalyzed with nanosized cobalt and nanosized nickel was found to release hydrogen at a temperature as low as 59 °C [He et al. 2009]. Also reduction in the activation energy was observed.
Use of alkaline earth metal hydrides i.e. magnesium hydride and calcium hydride [Zhang et al. 2010, Int. J. Hyd. Energy] and alkaline metal hydrides i.e. lithium hydride and sodium hydride [Zhang et al. 2010, J Phys Chem] was found useful in altering the thermodynamics and kinetics of AB decomposition. Several approaches, including use of metal organic frameworks either by mixing [Li et al. 2010] or by chemical incorporation [Li et al. 2010, Eur. Chem. J.], use of magnesium metal powder [Luo et al. 2010, J. Am. Chem. Soc], ionic liquids [Basu et al. 2011], zeolite-X and K-chabazite [Gangal et al. 2011] have been reported to improve dehydrogenation properties of AB either in terms of suppressing borazine formation, improving kinetics and thermodynamics or decreasing temperature of dehydrogenation. In general it can be stated that additives alter decomposition properties of AB to a great extent.
Interaction of silicon and hydrogen is widely studied as hydrogen helps passivation of the defects in silicon and improves its properties. Hydrogenation of silicon is done to improve its opto-electric properties. Hydrogenation of polycrystalline silicon thin films can reduce grain boundary defects and improve the solar cell efficiency [Honda S. et al., 2006]. Hydrogen is readily chemisorbed on Si dangling bonds [Le T. T. Tuyen et al., 2001]. Kale et al. have shown experimentally that hydrogen can be physisorbed as well as chemisorbed on silicon nanoparticles [Kale et al., 2011]. It is reported in the literature that H-H bond length in the hydrogen molecule is about 0.764 A while N-H bond length in AB molecule is 1.024 A and B-H bond length in AB molecule is 1.218 A [Lee S. M. et al. 2009]. Thus if silicon can disrupt H-H bond in hydrogen molecule we think that it can also assist disruption of N-H and B-H bonds in ammonia borane. The silica increases the rate of hydrogen release from the ammonia borane by two orders of magnitude compared with the release of hydrogen from ammonia borane

alone. Furthermore, heating the hybrid material above 3 7 OK to release the second equivalent of hydrogen gives rise to very little borazine, a volatile impurity that needs to be minimised to avoid poisoning Polymer Electrolyte Membrane Fuel cell (PEMFC). The studies so cited above shows there is problem to generate hydrogen at low temperature without improvement in kinetics of reactions. Also rate of generating hydrogen is slow with undesirable side products.
US patent 7,316,788 and US patent 7963116 describes materials for storage and release of bulk quantities of hydrogen and methods of making and using same. In these patents, a way to deposit ammonia borane within the porous channels of mesoporous silica has been disclosed. The drawback of the mesoporous scaffold is its weight. The team is now studying how the scaffold improves hydrogen release to develop a hybrid material that does not significantly add to the weight or volume of the ammonia borane systems.
Accordingly, there is need to generate hydrogen at much faster rate of reaction with improved kinetics and low induction period. Also there is need to suppress undesired products. The
SUMMARY OF THE INVENTION:
Ammonia borane found to be the desired material for the hydrogen generating material when additives are added. The present invention solves the problem of generating hydrogen in much simpler way with reduction in induction period and improvements in kinetics. The present invention discloses the composition of hydrogen generating material using catalyst and the method to synthesize this composition. Further, the present invention, thermal decomposition of neat AB and silicon nanoparticles doped AB under transient temperature conditions in a TGDTA system as well as under isothermal conditions in a constant volume standard Sievert's type apparatus is disclosed. A long induction period of 125 minutes was observed in case of neat AB decomposing at 90°C and gravimetric

hydrogen storage capacity of neat AB was estimated to be 4.2wt%. With addition of silicon nanopartides to AB by ball milling, this gravimetric storage capacity at 90°C increased to 5.4 wt% without any induction period. At temperature of 110°C, 30 minutes induction period was observed in case of neat AB and for ABSi the induction period was absent. At 135°C and 150°C induction period was not observed in both the samples and also the decomposition curves depicted same nature. The wt% released was found to increase with addition of silicon nanopartides for decomposition at 90°C, 110°C and 150°C, however at 135°C it was negligibly less as compared to AB. In TGA decomposition steps in case of AB and ABSi were found to be almost same with a little higher mass loss observed in case of ABSi as compared to AB. In DTA exothermic peak corresponding to second mass loss step of ABSi was absent and instead the reaction was found to be slightly endothermic suggesting gas solid reaction forming hydride. This indicates the possibility of regeneration of AB from the residues of decomposition. XRD and FTIR studies showed presence of silicon in the residues of decomposition indicating that silicon is acting as a catalyst. Also HRTEM confirmed nanosizing of silicon suggesting successful synthesis of silicon nanoparticles by ball milling. This is the first report of using silicon nanopartides as catalyst in decomposition of AB. Ball milling of silicon nanopartides with AB resulted in reduction of induction period and increase in the amount of gas released. Besides, the addition of silicon nanoparticles suppressed the foaming and swelling phenomenon as observed in case of neat AB thermolysis.
OBJECTS OF THE INVENTION:
It is an object of the present invention to provide a composition consisting of hydrogen storage material such as ammonia borane in particular and Silicon Nanoparticles which acts as a decomposition catalyst for the decomposition of hydrogen storage material.

It is another object of invention to use the said silicon nanoparticles as catalyst in lowering the decomposition temperature of ammonia borane along with reduction in the induction period and improvement in kinetics,
It is yet another object of invention is to synthesis the said composition of hydrogen storage material such as ammonium borane and silicon nanoparticles which in turn are made by a simple technique such as ball milling of porous silicon thin films in a most cost effective way and thus have the potential to serve in the immediate application of the invention that can release hydrogen at the conditions suitable for Polymer Electrolyte Membrane Fuel cell (PEMFC).
BRIEF DESCRIPTION OF THE DRAWINGS:
A complete understanding of the invention may be obtained by reference to the accompanying drawings when considered in conjunction with the following detailed description, in which:
Figure 1(a) is Transient Temperature decomposition behaviour of AB and ABSi examined by TGA.
Figure 1(b) is Transient Temperature decomposition behaviour of AB and ABSi examined by DTA.
Figure 2(a) is Isothermal decomposition of AB and ABSi at 90°C.
Figure 2(b) is Isothermal decomposition of AB and ABSi at 110°C.
Figure 2(c) is Isothermal decomposition of AB and ABSi at 135°C.
Figure 2(d) is Isothermal decomposition of AB and ABSi at 150°C.

Figure 3 is HRTEM of silicon nanoparticles, Inset: 4-5 run sized Si nanoparticles exhibiting differently oriented lattice fringes.
Figure 4 is XRD pattern of AB and ABSi and decomposition products of ABSi.
Figure 5a is FTIR spectra ofì¥Á 5@ ð ¿ ²u
bjbjÏ2Ï2 “ X X ²m ÿÿ ÿÿ ÿÿ ˆ 6 6 6 6 6 6 6 : þ þ þ þ \ and at (e) 150°C.
DETAILED DESCRIPTION OF THE INVENTION:
In an embodiment of the present invention, a composition is provided consisting of hydrogen storage material such as ammonia borane in particular and inorganic nanoparticles such as silicon nanoparticles which acts as a decomposition catalyst for the decomposition of hydrogen storage material.
The term "ammonia boranes" includes compounds containing N—H and B—H bonds such as compounds represented by formula NHxBHy, wherein x and y are independently an integer from 1 to 4 and do not have to be the same, including NH3BH3
In one embodiment of the present invention, thermal decomposition of neat AB and silicon nanoparticles doped AB under transient temperature conditions in a TGDTA system as well as under isothermal conditions in a constant volume standard Sievert's type apparatus is studied.

The term inorganic nanoparticles catalyst includes but are not limited to, members selected from the group of porous materials, such as, silica, silicon dioxide, mesoporous silica and more particularly porous silicon thin films.
The silicon nanoparticles catalyst can be effectively and efficiently dispersed in a hydrogen storage material comprising a complex hydride using a grinding technique. Non-limiting examples of grinding techniques include ball milling.
The ball mill, a type of grinder, is a device used to grind materials like ores, chemicals, ceramics and paints. The ball mill may rotate around a horizontal axis, a vertical axis, or an axis inclined between the horizontal and the vertical, partially filled with the material to be ground in addition to the grinding medium. An internal cascading effect reduces the reactants to a fine powder during the process. The grinding medium can be ceramic balls, or stainless steel balls coated with a ceramic. An exemplary ceramic is tungsten carbide. (It should be emphasized that other types of grinding media are also possible). The amount and size of balls, as well as size of the vessel, are selected to provide effective grinding of insoluble solids during the reaction. Planetary ball mills such as PULVERISETTE 6 can grind mixture particles to as small as nanometer dimensions, enormously increasing surface area and reaction rates.
Catalyst synthesis: Silicon nanoparticles were prepared by ball milling of porous silicon films. Freestanding porous silicon films were obtained by Two Step Separation (TSS) process. Ball milling was done in a Fritsch pulverisette-6 ball mill in 80 ml stainless steel (SS) bowl with 3 mm tungsten carbide (TC) ball set for 24 hours.
Homogenised mixing of hydride storage material and catalyst: Ammonia Borane (AB) 97 % pure was obtained from Sigma-Aldrich and was used as received.
In one of the embodiment, ammonia borane is provided in molar excess relative to the silicon nanoparticles. As an exemplary embodiment of composition

comprising an ammonia borane, and the silicon catalyst, combined in a molar ratio of about 10 to about 1 moles respectively.
The mass ratio of AB to silicon nanoparticles was kept 10:1. The mixture was ball milled for one hour using 10 mm SS ball set in 80 ml SS bowl with a milling cycle of 10 minutes milling followed by 10 minutes pause. Purpose of ball milling here was just to homogenize the mixture and no intention was there to reduce the particle size of material. This mixture of AB and silicon nanoparticles is referred as ABSi henceforth.
Decomposition of ABSi: Decomposition were performed on neat AB and on AB mixed with silicon nanoparticles. Isothermal decomposition was carried out in an indigenous standard Sievert's type apparatus and transient temperature experiments were performed in a Perkin Elmer TG/DTA system under flowing argon having flow rate of 50 ml/min from room temperature to 250°C. Isothermal decomposition was studied under vacuum at 90°C, 110°C, 135°C and 150°C. On heating, the sample decomposes and releases gases which can be observed by change in the pressure. This change in the pressure of the apparatus was used to estimate the amount of gas released with the help of van der Waals equation for real gases.
Decomposition of ABSi sample initiated immediately as the heating started. Endothermic melting event is observed at about 108°C which is delayed by about 8°C as compared to AB. In contrast to AB where three exothermic events were noticed after melting, only one exothermic event is observed following an endothermic melting event in case of ABSi. The weight loss steps almost coincide with that of AB except the initial weight loss observed in ABSi which is absent in case of AB. Also decomposition of ABSi is significantly less exothermic as compared to AB. Particularly, only the first decomposition step is found to be exothermic in case of ABSi and no exothermic events were found corresponding

to the second major weight loss step but in contrast the reaction was observed to be slightly endothermic.
The effect of silicon nanoparticles addition on thermal decomposition of AB, further volumetric measurements were carried out on AB and ABSi at constant temperature of 90 °C, 110°C, 135°C and 150°C in vacuum. Isothermal decomposition behaviour of AB and ABSi is compared in figure 2. The sigmoid nature of decomposition curve of AB at 90°C in figure 2a is similar to that reported in literature where the three stages namely induction, nucleation and growth are observed. Unlike AB, where induction period is about 125 minutes in ABSi although the decomposition curve is sigmoid in nature, no induction period is observed for 90oC decomposition. Absence of induction period is desirable property for practical hydrogen storage applications.
In addition to the reduction in induction period the amount of gas released is significantly high for ABSi when compared with AB. It is found that at 90°C ABSi releases 5.4wt% whereas AB releases only 4.2 wt%. Also the time required to release 4.2 wt% in case of AB is about 350 minutes whereas the same amount is released in about 200 minutes in ABSi. Decomposition reaction is initially slow in case of ABSi till it releases about 0.7 wt% in about 100 minutes. Then the reaction accelerates for the next 100 minutes releasing a total of about 4.2 wt% in 200 minutes and finally the reaction decelerates. Absence of induction period in ABSi is in well agreement with the TGA curve in figure la where weight loss starts immediately as the heating starts. The wt% in case of ABSi is calculated by taking into account the weight of silicon nanoparticles. Similar isothermal measurements were performed at 110°C, 135°C and 150°C and the results are presented in figure 2b, 2c and 2d respectively. It is observed that at 110°C decomposition is much faster as compared to that at 90°C. Induction period of 30 minutes is observed for AB while for ABSi there is no induction period observed which is as expected. When the sample temperature and the time coordinate were carefully examined it was found that the induction period of 30 minutes observed

at 110°C decomposition is the time required by the sample to attain the temperature of about 100°C. After the temperature of about 100°C is reached the sample decomposes vigorously releasing large quantity of gas in a short time and then the reaction curve becomes flat taking long time to stabilize. At 110°C AB releases about 7 wt% and takes a total time of about 400 minutes for this gas release. The same amount is released in about 100 minutes by ABSi sample. Also the total amount released by ABSi is about 7.9 wt% which is quite high as compared to AB and it is released in about 225 minutes only. Except for the little induction period in case of AB and difference in the amount of gas released, the nature of curve is same for both AB and ABSi at 110°C. At 135°C, both AB and ABSi show almost same decomposition curve. The amount of gas released is negligibly higher for AB as compared to ABSi. Both curves show rapid gas release initially for about 50 minutes where about 7.5 wt% is released and then a flat region till the end of reaction. Total amount released is about 10 wt% for both AB and ABSi which is quite higher as compared to that released at 90°C and 110°C. Decomposition curves at 150°C are similar to that at 135°C. Here too induction period is absent. AB shows faster gas release as compared to ABSi initially upto about 50 minutes after which the decomposition curve for AB is seen to stabilize releasing 12 wt% in about 300 minutes. Initial 10 wt% is released in only 25 minutes in case of AB while for the same amount to be released it takes about 50 minutes for ABSi. But the total amount released by ABSi is about 13 wt% which is quite high as compared to AB. Also the total time needed for releasing that wt% is only 150 minutes which is significantly less as compared to AB.
Characterisation of Materials: Materials were characterized by X-ray diffractometry (XRD) analysis using Philips Xray Diffractometer using Cu Ka radiation having wavelength 1.54 A within the 20 range of 10° to 60°. A Fourier Transform Infra Red (FTIR) spectrum of the materials was recorded using Jasco FT/IR-6100A system in the range of 400 cm'1 to 4000 cm"1. XRD and FTIR

measurements were carried out on neat AB, ABSi and on the spent ABSi sample after thermal decomposition. Nanosizing of silicon was confirmed by HRTEM.
Figure 1 shows the thermal decomposition behaviour of AB and ABSi examined by TG/DTA. For AB, an endothermic melting peak is observed at about 100 °C. Following the melting event three exothermic events were noticed with the peaks observed at approximately 118°C, 149°C and 173°C. These exothermic events correspond to the decomposition steps and probably forming polymeric amidoboranes and polymeric imidoboranes respectively
Silicon nanoparticles were examined by HRTEM to estimate the average particle size. Particle size calculated from HRTEM image of the as prepared Si nanoparticles powder shown in figure 3 exhibits a range of 4 to 20 nm. Figure 3 HRTEM of silicon nanoparticles, Inset: 4-5 nm sized Si nanoparticles exhibiting differently oriented lattice fringes. Porosity of the films was determined using gravimetric method and was found to be 29%.
Figure 4 shows XRD pattern for AB, ABSi and the decomposition products collected after isothermal decomposition of ABSi. The XRD pattern of AB shows sharp peaks exhibiting crystalline nature and well matches with JCPDS reference no: 01-074- 0894 suggesting tetragonal structure of AB. XRD pattern of ABSi shows peaks corresponding to AB as well as silicon. This clearly indicates that no solid phase reaction occurs between AB and silicon. AB peaks can be seen clearly whereas silicon peaks are not very sharp. This may be due to low loading or poor crystallinity of silicon. But a careful observation of the XRD pattern confirms the existence of both AB and silicon separately.
After decomposition at 90°C XRD peaks corresponding to AB disappeared. XRD pattern of solid residue obtained after decomposition of ABSi at 90°C referred as ABSi_90C is shown in figure 4. Two broad peaks at 2 Theta values nf 23 6° and 48.5° were observed suggesting formation of amorphous decomposition species.

Absence of silicon peaks indicated participation of silicon nanoparticles in the reaction. Carefully matching the peaks and profile with JCPDS reference patterns suggested formation of a polymeric compound Borane Amide with chemical formula (BH2NH2)5 and the JCPDS reference no. 00-019-0418. Similarly XRD pattern of residue after decomposition at 110°C, 135°C and 150°C did not show any sharp peaks however the 15 OX pattern well matched with silicon (JCPDS reference no.: 00-040-0932) indicating that silicon nanoparticles worked as catalyst and remained unaffected in decomposition process.
Figure 5a and 5b show FTIR transmittance spectra of AB and ABSi whereas figure 6 shows FTIR spectra of ABSi and its decomposition products. It can be seen from figure 5a that after milling AB with silicon nanoparticles N-H band near 1600cm"1 has disappeared while that near 1400cm"1 is slightly shifted. Also the B-N stretching band near 782cm'1 is affected. As seen in figure 5b, the B-H stretching frequencies in the range of 2100cm"1 to 2400cm"1 are also affected and the effect is seen in terms of broadening of the transmittance peaks. Similar effect is observed for N-H bands in the range of 3100cm'1 and 3300cm'1. Except for these few changes no appreciable change is observed in the FTIR spectra of AB and ABSi. Surprisingly no peaks were observed corresponding to silicon which may be due to small amount of silicon present in ABSi and because no solid phase reaction occurs during ball milling. FTIR spectra of ABSi decomposition residue after decomposition at 90°C} 110°C, 135°C and 150°C are shown in figure 6. As the temperature of decomposition increases from 90°C to 150°C N-H and B-H bands get broadened and finally disappear. No bands corresponding to silicon or Si-H are found in the FTIR spectra of decomposition products indicating that the silicon nanoparticles act as catalyst and do not form any chemical bond. This is in well agreement with the XRD results which also suggested that silicon nanoparticles act as catalyst only. B-N bands in the range 700cm'1 to 900cm"' are seen weakened but still exist thus ruling out the possibility of disruption of B-N bonds and ammonia formation.

We claim:
1. A composition for generating hydrogen comprising,
a. a solid state hydrogen storage material.; and
b. an inorganic nanoparticle catalyst,
wherein the amount of catalyst relative to the ammonia-borane complex is 5 wt% - 15 wt%.
2. The composition of claim 1, wherein the solid state hydrogen storage material comprises a chemical hydride.
3. The composition of claim 2, wherein the chemical hydride is ammonia borane.
4. The composition according to claim 3, wherein the chemical hydride is an ammonia borane selected from the group consisting of compounds of formula NHxBHy, wherein each of x and y is any integer from 1 to 4 and do not have to be the same.
5. The composition of claim 1, wherein the inorganic nanoparticle catalyst comprises Silicone.
6. The composition of claim 5, wherein the said Silicone consists of porous silicon films.
7. The composition of claim 5, wherein the size of said inorganic nanoparticle catalyst is in the range of 4 nm to 25 nm.
8. A method for making a hydrogen generating composition, comprising the steps of:

(a) ball milling an inorganic catalyst for 24 hours providing nanoparticles of size 4 nm to 25 nm;
(b) mixing ammonia borane (AB) and the said inorganic nanoparticle catalyst by ball milling thereby providing homogenised mixture;
(c) thermally initiating the said homogenised mixture to generate hydrogen.
9. The method of claim 9, further comprising heating the mixture to a
temperature range between 90°C to 150°C.

10. The method of claim 10, wherein weight percentage of hydrogen generated is 5 to 13 for said temperature range.
11. A system of hydrogen generation comprising:
a composition having a solid state hydrogen storage material; and inorganic nanoparticle catalyst, the said composition when homogenised and then thermally decomposed, generate bulk quantities of hydrogen with reduction in the induction period of decomposition of said composition at temperature range between 90°C to 150°C and with improvement in kinetics than said solid state- hydrogen storage material when thermally decomposed in absence of said inorganic nanoparticle catalyst.

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Patent Number

268706

Indian Patent Application Number

2533/MUM/2011

PG Journal Number

38/2015

Publication Date

18-Sep-2015

Grant Date

14-Sep-2015

Date of Filing

09-Sep-2011

Name of Patentee

INDIAN INSTITUTE OF TECHNOLOGY, BOMBAY

Applicant Address

INDIAN INSTITUTE OF TECHNOLOGY, BOMBAY, POWAI,MUMBAI-400076,MAHARASHTRA,INDIA

Inventors:

#	Inventor's Name	Inventor's Address
1	ANEESH CHINTAMAN GANGAL	DEPT.OF ENERGY SCIENCE AND ENGINEERING,IIT BOMBAY,POWAI,MUMBAI-400076
2	PRATIBHA SHARMA	DEPT.OF ENERGY SCIENCE AND ENGINEERING,IIT BOMBAY,POWAI,MUMBAI-400076
3	PARESH KALE	DEPT.OF ENERGY SCIENCE AND ENGINEERING,IIT BOMBAY,POWAI,MUMBAI-400076

PCT International Classification Number

C07D 209/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA