Preparation Of Low Loading Noble Metal Composite Catalyst And Its Electrocatalytic Performance For Water Splitting

Nowadays,environmental pollution and energy crisis are imminent,making it more urgent for people to seek clean and sustainable new energy to replace the traditional fossil fuel.Hydrogen energy,as a new type of energy,has been widely considered as the most competitive substitute of fossil fuels because of its advantages such as environmental protection,abundant reserves and cleanliness.But until now,most of the hydrogen energy on earth has been produced by converting hydrocarbons,and the process inevitably creates waste that is not good for the environment.Therefore,electrolysis of water to produce hydrogen,which is a simple and environmentally friendly new way of hydrogen production,has been widely studied.To this end,scientists continue to explore efficient,durable and economic electrocatalysts to meet the requirements of hydrogen production.Today,the most commercially advanced catalyst materials are noble metal catalysts such as Pt electrodes for hydrogen evolution（HER）and Ru O₂ or Ir O₂ electrodes for oxygen evolution（OER）.However,their high cost and low earth abundance limit their large-scale application in the field of water electrolysis.In recent years,inexpensive and easily available transition metal-based catalysts have shown excellent electrochemical performance due to their unique electron configurations,showing the potential to replace precious metals as catalysts for electrolysis of water.This paper mainly in view of the transition metal compounds with high abundance of natural,price is low wait for an advantage,low content of precious metals by load,thus the morphology of from material,structure and the intrinsic activity of transition metal catalysts are modified,and allow it to come to the precious metal catalyst has excellent hydrogen evolution and oxygen evolution electrolysis of water performance.The specific research is as follows:1.At the same time,the study of electrocatalyst materials with efficient hydrogen evolution reaction in a wide pH range has attracted widespread attention.Using simple and gentle methods to synthesize excellent catalysts is also a commonly sought method.Based on this,trace Ir doped transition metal carbide,Ir Cu C,is designed and synthesized by a simple solid-state mixing method at room temperature.The low load of Ir nanoparticles not only increased the number of active sites of Cu C precursors,but also increased the charge transfer rate,and improved the catalytic performance of Cu C precursors from the intrinsic activity of the materials,so as to improve HER,OER and the overall water cracking performance.The results show that in 0.5 M H₂SO₄ solution with a current density of 10 m A cm^-2,it has a low overpotential of 70 m V,and in 1.0 M KOH solution with a current density of 10 m A cm^-2,it also has a low overpotential of 72 m V,and it shows a high stability.This is not much different from the single precious metal catalyst,but the cost is low and the abundance is high.This new synthesis method provides a new way to search for excellent catalysts in the whole pH range.2.It is of great significance to study the monolithic water cracking catalyst with excellent hydrogen evolution reaction and oxygen evolution reaction.However,current researches mainly focus on electrocatalyst materials with excellent catalytic activity in a single environment.In this work,the IrNPs@Fe NC nanorods is synthesized by simple pyrolysis and etching materials,which can be used as a high bifunctional catalyst for water decomposition.Due to the presence of Fe SAs coordination with N groups（Fe-N）in the carbon matrix of IR NPs@Fe NC electrocatalytic materials,large size IRNPs can be dispersed into IRSAs stabilized by N groups（IR-N4）and smaller IRNPs.Therefore,IRSAs with low hydrolytic dissociation barrier and IRNPs with appropriate hydrogen absorption/desorption intensity synergistically enhance the hydrogen and oxygen evolution performance of electrolytic water under alkaline conditions.This work provides a new idea for the synthesis of bifunctional monolithic water cracking materials under alkaline conditions.3.Nowadays,the MoS₂ material has received extensive attention due to its unique sheet structure,and there are more and more studies on its improvement to improve its water splitting ability.In this work,the MoS₂ catalyst material Fe Pt@MoS₂ loaded with Fe Pt nanoparticles is designed and synthesized by a simple hydrothermal method,which has excellent hydrogen evolution catalytic activity under alkaline conditions.By doping with a low loading of precious metal Pt,the synthesized Fe Pt@MoS₂ has good catalytic performance.The main reason is that Pt Fe doping modulates the phase transition of MoS₂and induces the transition from the semiconductor 2H-MoS₂ phase to more stable The metal 1T-MoS₂ is doped with Fe Pt to replace part of Mo atoms to introduce more S vacancies,change the morphology and structure of flake MoS₂,thereby improving its electrocatalytic hydrogen evolution activity.The Fe Pt@MoS₂ catalyst obtained under alkaline conditions has an overpotential of 130 m V and good stability at a current density of 10 m A cm^-2,which provides ideas for the future design of excellent hydrogen evolution catalysts under alkaline conditions.