Preparation Of Cobalt And Carbon–based Transition Metallic Hybrid Materials And Their Applications In Hydrogen Evolution Reaction

Among various catalytic reactions,electrocatalysis has gradually stood out and attracted researchers’ attention.Compared with traditional catalytic reactions which require high-temperature and high-pressure conditions,electrocatalytic reactions have better prospects because of their simple reaction conditions as well as the features of electricity of being safe,economical and environment-friendly.Studies have proved that Co based compounds possess rich storage capacity as well as catalytic properties similar to precious metal materials and are widely used in electrocatalytic reactions.As typical transition metals,cobalt-based materials are considered as one of the most promising catalysts.However,due to its lack of stability and easy agglomeration,its development is obstructed.To solve the problem,carbon-based materials are used as catalyst carriers,which can not only make the two(transition metals and carbon-based materials)produce a synergistic effect to effectively avoid agglomeration of metal particles,but also enhance the conductivity of the catalyst,promoting electrocatalytic reactions.In this research,composite nanomaterials are prepared with carbon-based materials as carriers and cobalt-based materials as the main active sites,and then are applied to electrocatalytic hydrogen evolution reactions.The main research contents and conclusions are as following:1.Using the two-step calcination method,the researcher synthetizes nitrogendoped graphene/carbon nanotube multi-stage carbon material with carbon-coated cobalt phosphide nanomaterials,and then applies the material to electrocatalytic hydrogen evolution reactions.Morphological analysis reveals that the cobalt phosphide nanoparticles are evenly distributed on the surface of the multi-level carbon material.This unique multi-level structure can provide larger catalytic active sites and excellent electrical conductivity for electrocatalytic reactions.Experimental results demonstrate that the composite material displays convincing electrochemical properties2.With ZIF-67 as a template,the dodecahedral carbon material loaded with ruthenium-doped cobalt nanoparticles is prepared using the calcination method and the ion exchange method,and the material is used in the electrocatalytic hydrogen evolution reaction.The synthetic method is simple and quick.During the calcination process,the volatilization of zinc leaves a large number of pores on the surface of the material,greatly increasing the specific surface area.The incorporation of ruthenium as catalytic sites is able to effectively increase the catalytic activity of the catalyst.