Transition Metal Phosphide As A Catalyst For The Hydrolytic Dehydrogenation Of Ammonia Borane And Sodium Borohydride

With the merits of abundance,high energy density and environmental friendliness,hydrogen is recognized as one of the desired green energy resource.In order to achieve widespread application,the main problem should be solved is how to efficiently and safely store and transport hydrogen.Due to the high hydrogen storage density and small volume,chemical hydrogen storage materials?NaBH₄,NH₃BH₃,N₂H₄,CH₃OH,etc.?can effectively solve the mentioned problems.To achieve fast and efficient release hydrogen,the most effective way is to find a cheap and efficient catalyst.Transition metal phosphides are widely used to catalysis for hydrogen generation from hydrolysis of chemical hydrogen storage materials.In this paper,we aim to develop a series of cheap and efficient transition metal phosphide as the hydride hydrolysis catalysts for ammonia borane and NaBH₄.Meanwhile,we modified the optimum hydrolysis conditions for hydrogen production.The results are as follows:1.Introducing cheap sodium phosphate,nitric acid cobalt,cobalt chloride as the precursors,a series of transition metal phosphides?CoP,Co₂P,Ni₂P,Cu₃P and FeP?nanoparticles were synthesized and characterized by XRD,SEM and TEM.2.Co₂P was used as the catalyst for hydrolysis of ammonia borane.The reaction conditions were optimized.The results show that the amount of catalyst,the concentration of ammonia borane,alkali concentration and reaction temperature have a great influence on the hydrolysis efficiency of ammonia borane.3.We compared the catalytic efficiency of different transition metal phosphides under the same condition and the results showed that the best catalystic efficiency was CoP,Co₂P was the second and FeP was the worst.4.Compared with other reported Co-P catalysts for hydrolysis of NaBH₄,CoP nanoparticels demonstrated a better catalytic efficiency and stability.At 25 ?and 35?,the TOF values of CoP catalyzed hydrolysis of NaBH₄ were 3097.62 mL×min^-1×g^-1 and 4704.14 mL×min^-1×g^-1,respectively.5.Co₂P nanoparticles were used to catalyze the hydrolysis of sodium borohydride aqueous solution to produce hydrogen,and the reaction conditions were optimized.The relative TOF values measured at 30 ?and 35? were 2307.2 mL×min^-1×g^-1 and 3323.4 mL×min^-1×g^-1,respectively.