Synthesis Of Transition Metal Phosphides Based On Template Conversion Strategy And Their Electrocatalytic Hydrogen Evolution Properties

Hydrogen fuel is a green and renewable energy resource that could replace fossil fuels in the future.Electrolysis of water is a clean and sustainable approach for hydrogen production.To date,Pt is still considered as the best electrocatalyst toward hydrogen evolution reaction(HER);however,the high cost,scarcity,and poor stability in alkaline greatly limit its widespread application.In recent years,transition metal phosphides(TMPs)have been discovered to exhibit excellent HER catalytic activities.Although some progress has been made with TMPs as HER catalysts,there are still some problems to be resolved.For example,a few of TMPs can exhibit comparable to,or even better activities than commercial Pt/C,but most had poor activity and stability in alkaline.Given that,in this thesis we aim to explore new routes to prepare TMPs and to investigate their activities and stabilities when used as catalysts for HER.The main contents are summarized as follows:(1)Amorphous ruthenium nanoparticles(Rh)with an average size of 2 nm were synthesized in large scale through a simple solvothermal route.After Rh was loaded on activated carbon,the composite of Rh2P nanoparticles and activated carbon(Rh2P/C)was prepared by a gas-solid method.The experimental results revealed that the as-prepared Rh2P/C exhibited excellent catalytic activity and stability at pH-universal HER.Strikingly,the activity and stability of catalyst in HER under alkaline condition were obviously higher than that of the commercial Pt/C.(2)Octahedral particles of metal-organic framework HKUST-1 were used as template to synthesize hollow carbon doped Cu3P and carbon-coated CU3R by means of direct phosphorization method and carbonization/phosphorization two-step method,respectively.The experimental results showed that the CU3R with hollow structure had better HER activity and excellent stability.And we found that the incorporation of Ru nanoparticles in the composites could effectively improve the HER activity of carbon-coated Cusp catalysts.(3)Cu-MOF-74 coated copper nanowires with core-shell structure were synthesized by the self-sacrificial template method.Experiments indicated that the thickness of Cu-MOF-74 layers could be tuned by controlling the reaction time.The H2O2 sensing tests demonstrated that the Cu-MOF-74 layer on the surface of copper nanowires could enrich H2O2,thereby enhancing the response signal.However,TEM observation revealed that the Cu-MOF-74 shell had been destroyed to a certain extent after testing.