Design And Performance Study Of Cobalt Molybdenum Based Electrocatalyst For Overall Water Splitting

In order to resolve the energy crisis and obtain sustainable,renewable energy.Splitting water into hydrogen and oxygen has drawn tremendous research interest as an appealing solution.There action of water splitting electrolysis consists of the oxygen evolution reaction?OER?and the hydrogen evolution reaction?HER?,but both parts require the catalyst to possess high activity,high stability and economical.The Cobalt molybdate,as an excessive metal oxide,possess stable crystal structure and strong redox,which is considered to be an electrocatalyst with great development potential.However,the low utilization of active sites and poor stability limit application of it.Therefore,we supply a gap by doping,reduction and other methods based on cobalt molybdate materials,In order to reduce the kinetic energy barrier of water decomposition,increase the specific surface area,and improve the stability,so as to build a new and efficient electrocatalyst.a series of phosphorus-doped CoMoO₄ rod bundles electrocatalysts on 3D nickel foams have been successfully synthesized and exploited as efficient hydrogen evolution reaction?HER?electrocatalyst in 1 M KOH.The incorporation of phosphorus into CoMoO₄ can significantly promote the HER activity and the CoMoO₄ bundles phosphorized at 350?C exhibited the optimum activity,which only required low overpotentials of 56 and 148 mV to deliver cathodic current densities of 10 mA cm-2 and 100 mA cm-2,respectively.This electrode also presented considerable long-term electrochemical stability with negligible delay after 30 h operation and 3000 accelerated cyclic voltammetry cycles.As the temperature phosphorized increase to 450?C,the CoMoO₄ bundles covered to CoMoO₃ and greatly enhanced its oxygen evolution reaction performance.At 10 mA cm^-2,this P-CoMoO3 exhibited superior electrocatalytic activity of low overpotentials of 267 m V for OER in alkaline media.Our study provides a superior earth-abundant catalyst for efficient HER and OER in alkaline media,which also suggests that P doping engineering is an effective way to boost the HER and OER activity of transition-metal based oxides.Otherwise,we report on our recent effort in designing and synthesizing CoO/MoO_x and CoMoO₄/MoO_x which were also based on CoMoO₄ by the high-purity hydrogen with different temperature.Under different hydrogen temperatures to prepare catalyst based on CoMoO4.The CoO/MoOx and CoMoO4/MoOx electrode exhibited excellent electrocatalytic performances for the HER and OER of 47 mV and 283 mV,respectively,at 30 mA cm^-22 in an alkaline solution.Furthermore,The water–alkali electrolyzer using CoO/MoOx as cathode and CoMoO4/MoOx as anode achieves stable overall water splitting with a small cell voltage of 1.6 V at 20 mA cm^-2.