Preparation Of Multi-component Transition Metal Phosphide Composites And Its Water Splitting Performance Research

Increasing global warming and depleting fossil resources make the need to develop clean and renewable energy more urgent.Hydrogen energy,which has the advantages of high energy density,renewability,and environmentally friendly clean fuel,is expected to alleviate the energy crisis.Water electrolysis is a promising method for hydrogen production.The high energy level barriers of hydrogen evolution reaction（HER）and oxygen evolution reaction（OER）involved in water splitting reaction limit the energy conversion efficiency of HER and OER.Transition metal-based phosphide electrocatalysts with high catalytic activity that can replace traditional noble metal-based catalysts are the key to promoting the development of water electrolysis for hydrogen production.In summary,this paper takes transition metal phosphide materials as the research object,and by optimizing the element composition and structure,a series of transition metal phosphide composite materials are prepared,and their water splitting properties are studied.Electrocatalyst research provides new design ideas.The main research contents are as follows:It is proposed to obtain ternary transition metal phosphide to replace noble metal catalyst by high-throughput screening.FeCoNiP composites with different concentrations were prepared by hydrothermal synthesis and high temperature phosphating reaction using nickel foam as base.The best Fe₂₀Co₆₀Ni₂₀P was selected by contour map.It is worth noting that when the Fe₂₀Co₆₀Ni₂₀P/NF||Fe₂₀Co₆₀Ni₂₀P/NF system operates continuously and stably for 24 hours at an over potential of 1.56V in alkaline electrolyte with a current density of 10 mAcm^-2.The excellent electrocatalytic activity of Fe₂₀Co₆₀Ni₂₀P are attributed to its 3D porous skeleton structure and reduced binding energy due to the synergistic action of ternary transition metals.Fe₂₀Co₆₀Ni₂₀P composite material as a non-noble metal catalyst has a great application prospect in industrial hydrogen production.Using carbon cloth as a base,by hydrothermal synthesis method preparation of sheet Co（OH）₂ precursor,further by dimethyl imidazole solution soaking and corrosion of sodium molybdate solution preparation of sheet Mo doping Co（OH）₂,the further preparation of the two-dimensional array structure through high temperature phosphating MoP/CoP coupling water decomposition catalyst used in electrochemical decomposition reaction.In 1 M KOH solution,HER activity(η₁₀=43 mV;η₁₀₀=145mV;Tafel slope=80 mVdec^-1),OER activity(η₁₀=150 mV;Tafel slope=77 mVdec^-1).The excellent electrocatalytic activity of MoP/CoP coupled water decomposition catalyst with two-dimensional array structure is attributed to its lamellar array structure which facilitates the dissociation of hydrogen and the charge transfer of metal atoms induced by phosphating.This work provides guidance for the structural design and composition of catalysts.