Preparation Of Electrode Materials Based On Cyanide Complex And Their Applications In Electrochemical Hydrogen Evolution Reaction

Hydrogen,as a pollution-free,high-calorie and renewable energy,is the most promising substitute of traditional fossil fuels.In recent years,electrochemical water splitting has attracted considerable attention due to its high efficiency of hydrogen generation.The process of water splitting includes two key steps,which are hydrogen evolution reaction(HER)on the cathode and oxygen evolution reaction(OER)on the anode.In this work,the cobalt disulfide/iron disulfide(FeS2/CoS2)and palladium/tricobalt tetroxide(Pd/Co3O4),two kinds of HER catalysts based on cyanide complexes,were prepared on carbon cloth(CC).And their electrocatalytic activity toward HER on the cathode were studied.In the first chapter,the relevant concepts and research progress about electrochemical hydrogen evolution reaction are briefly introduced.The classification of electrode material and the application of transition metal phosphide as HER catalyst in recent years are mainly described.In the second chapter,cobalt carbonate with uniformly spiny tructure is grown on carbon cloth(CC)by a low-temperature hydrothermal method,and then cobalt ferricyanide is converted from cobalt carbonate through partially anion exchange with potassium ferricyanide.After annealed in hydrogen sulfide,the cobalt disulfide/iron disulfide with abundant lattice defects were obtained.The cobalt disulfide/iron disulfide exhibit excellent HER catalytic activity with an overpotential of 205 mV to achieve the current density of 100 mA cm-2 in acidic solution.In the third chapter,a layer of palladium cobalt cyanogel is decorated on carbon cloth by the reaction of chloropalladic acid and potassium hexacyanocobaltate,and then the cyanogel is transformed into palladium/Co3O4 using high-press water vapor at 250?.After the electrochemical activated by continuous CV cycling in acid solution,more palladium active sites are exposed by acid leaching of cobalt species,and thus the sample shows a significantly improved HER catalytic activity.The catalyst exhibits the current density of 100 mA cm-2 at a remarkly small overpotential of 130 mV and shows a long-term stability.