CoP Nanoarrays For Efficient Furfural Oxidation Assisted Hydrogen Evolution

Mass consumption of non-renewable fossil fuels has caused serious global energy crisis and environmental pollution problems,which has triggered plenty of researches on alternative,sustainable and clean energy sources.Hydrogen can be obtained from water splitting,which has been considered to be the most promising alternative to fossil fuels.Electriccatalytic hydrogen production can take advantage of the electricity obtained from renewable energy,such as solar,wind and so on,to power the production of hydrogen,therefore it is widely considered as one of the most promising hydrogen production technologies.Electrochemical water splitting includes two half reactions,namely the oxygen evolution reaction（OER）and hydrogen evolution reaction（HER）.However,OER is a slow dynamic process,by which the rate of water splitting is severely hindered.Based on this,it is necessary to develop novel and efficient electrocatalysts as well as the corresponding synthetic strategies towards hydrogen production.The chemical-assisted hydrogen electrocatalytic evolution strategy,for substituting for the kinetically slow OER process with more favorable oxidation reactions,has been developed to lower the energy consumption and favor the large scale production of hydrogen production by electrocatalytic water splitting.Furfural is one of the most important derivatives of furan ring system,from which we can obtain various value-added derivatives.Having the advantages of relatively low cost and high abundance compared with precious metal,environment-friendliness and high catalytic performance,cobalt-based materials have been found to be competitive candidates for the overall water-splitting among various transition metal-based electrocatalysts.In these catalysts,due to the good conductivity and electrocatalytic activity,cobalt phosphide shows promising performance for water splitting.Therefore,the strategy of furfural oxidation assisted hydrogen evolution has been proposed and cobalt phosphide nanoarray growing on carbon cloth（CoP/CC）has been developed as both anodic and cathodic electrocatalysts.（1）Facile synthesized Co-OH-F/CC material as electrocatalyst for Furfural Oxidation Assisted Hydrogen EvolutionCo-OH-F nanoarraies were grown on carbon cloth by a simple hydrothermal strategy.The morphology and composition of prepared Co-OH-F/CC was characterized by SEM and XPS and the electrocatalytic performance was characterized through cyclic voltammetry.When serving as the anodic electrocatalyst,Co-OH-F/CC material needs a voltage of voltage 1.587 V to obtain the current density of 10 mA cm^-2in 1 M KOH solution,which reduces to 1.458 V after furfural addition into the electrolyte,which suggests that furfural oxidation has replaced the anodic OER process.（2）Facile synthesized CoP/CC for efficient Furfural Oxidation Assisted Hydrogen EvolutionCoP/CC can be obtained by one-step phosphorization of Co-OH-F/CC.The obtained CoP/CC material keeps the original morphology of the precursor,which is in favor of the enhancement of electroactivity.The electrochemical performance of CoP/CC material towards OER,HER as well as furfural oxidation were tested in 1 M KOH electrolyte.Especially,when serving as anodic electrocatalyst,CoP/CC presents much reduced voltage from 1.596 V to1.234V to obtain a current density of 10 mA cm^-2 after adding furfural to the electrolyte,which demonstrates that the kinetically slow OER process has been replaced by furfural oxidation reaction.Moreover,value-added products,e.g,furfuryl alcohol and furfuryl acid,can be obtained at the anode.