Preparation Of Supported NiPt Catalyst And Its Catalytic Performance For Dehydrogenation Of Ammonia Borane

Hydrogen,which is with the characteristics of high energy densities and zero pollution of combustion products,is considered as one of the most promising clean energy.Hydrogen can fundamentally be an choice for solving the problems of the dependence on traditional fossil energy and the greenhouse effect and pollution which are associated with traditional fossil energy in contemporary society.The ammonia borane（AB）,which is of higher hydrogen storage density（19.6 wt%）and can be completely dehydrogenated with the presence of catalyst,is an ideal hydrogen storage material.This thesis mainly studies the preparation,characterization and catalytic performance of NiPt metal catalyst.（1）Ni_xPt_y/g-C₃N₄catalyst was prepared by immersion-reduction method which was loading NiPt onto g-C₃N₄carrier for catalytic dehydrogenate of AB.Catalyst Ni₅Pt₅/g-C₃N₄showed the highest catalytic activity in the whole AB dehydrogenate system at 283 K.Its TOF value is 1818 h^-1,and it has excellent cycle stability.After10 cycles,the TOF value is 909.3 h^-1,which retains 50%of the initial catalytic activity and is higher than other heterogeneous catalysts of the same type.（2）Using LiCl as template and melamine as precursor,g-C₃N₄nanosheets（g-C₃N₄NSs）were prepared as carriers,and NiPt/g-C₃N₄NSs catalysts were prepared by impregnation-reduction method loading of bimetallic NiPt.The catalysts was observed by XRD,XPS,N₂adsorption/desorption,TEM and other characterization methods.The TEM results showed that the diameter of the nanoparticles was 2.6±0.8nm..Catalytic AB dehydrogenate exhibited higher catalytic activity and stability at273 K,among which Ni₅Pt₅/g-C₃N₄NSs-5 had the best catalytic performance.The TOF value is 1818 h^-1,and 52%of the initial activity is retained after 10 cycles,which is superior to the reported catalyst values.