Study On Preparation And Catalytic Performance Of Supported Ni-Pt Catalysts For Dehydrogenation Of Hydrous Hydrazine

In light of the upcoming energy crisis and the increasingly severity of environmental pollution it is desirable to use sustainable, renewable and clean energies. Hydrogen, whose only byproduct is water, is an environmentally attractive and ideal energy carrier, especially for electricity generation in low-temperature fuel cells. However, despite the numerous studies conducted over several decades, the hydrogen economy has not been fulfilled due to the challenges in safely and efficiently storing hydrogen. Chemical hydrogen storage is a promising solution because it can be conveniently transported and has a considerable hydrogen content.Hydrous hydrazine, such as hydrazine monohydrate, is considered a promising candidate for storing hydrogen. It is advantageous due to its high hydrogen storage capacity(8.0 wt%), the production from complete decomposition of hydrous hydrazine is only hydrogen in addition to nitrogen. Therefore, the above two kinds of hydrogen storage materials. In this thesis, the main results are divided into two parts as following:Firstly, Here we demonstrate that the combination of NiPt alloy nanoparticles with a graphitic carbon nitride(g-C3N4) support facilitates H2 production from hydrous hydrazine in an alkaline solution under moderate conditions. Of all the heterogeneous catalysts tested, Ni37Pt63/g-C3N4 shows superior catalytic performance with a maximum initial turnover frequency(TOF) of 570 h- 1at 323 K and the hydrogen selectivity can reached 100%, N2H4?H2O can be completely decomposed during 5 minutes and showed superior catalytic performanceSecondly, We report for the first time a facile method by which bimetallic PtNi nanoparticles with various molar ratios were successfully immobilized on SBA-15, to be used as catalysts for hydrogen release by dehydrogenation of N2H4 ? H2 O. The performance of these catalysts, as indicated by the turnover frequency(TOF),depended on the composition of the prepared catalysts. Research results show that,Pt6Ni4/SBA-15 exhibited exceedingly high activity for decomposing hydrous hydrazine into high-quality H2 at 323 K, with 100% selectivity and the maximum TOF of 1132 h-1. N2H4·H2O can be completely decomposed during 3minutes.Therefore, the Pt6Ni4/SBA-15 catalysts have broad application prospects.