Study On The Performance Of Non-oxygen-evolving Metal Oxides In 2e-WOR

As an important green inorganic chemical product,hydrogen peroxide is widely used in medical,food,environmental protection,chemical and other fields.At present,the large-scale production of hydrogen peroxide in the industry mainly relies on the anthraquinone self-oxidation method,which has high energy consumption and is not environmentally friendly.At the same time,the high-concentration hydrogen peroxide produced also has huge safety hazards in transportation.Although the direct synthesis of H₂ and O₂ provides an alternative idea,there is a risk of explosion when the two are mixed,and the precious metal catalyst required for direct synthesis also hinders the practical application of this method;although oxygen reduction provides a safer and environmentally friendly production path,the high cost of oxygen reduction catalysts and the need for continuous oxygen in the production process also make it face great limitations.In contrast,the electrochemical water oxidation in-situ synthesis of hydrogen peroxide provides an attractive new route for hydrogen peroxide production due to its safety,environmental protection,simplicity and ease of use.However,electrocatalytic water oxidation to produce hydrogen peroxide is facing a huge challenge in selectivity,and it is very important to find suitable catalytic materials for water oxidation to produce hydrogen peroxide.This article focuses on the two competing reactions of hydrogen peroxide and oxygen in the electrocatalytic water split anode reaction.Based on the d-band theory,select and synthesize metal oxides that are not conducive to the oxygen evolution reaction from the perspective of thermodynamics and electrons,and carry out the electrocatalytic water oxidation of these materials.Study on the activity of hydrogen peroxide production.（1）Based on the d-band theory,metals containing d orbital active centers are beneficial to the occurrence of oxygen evolution reactions in water splitting.Select and synthesize three kinds of metal oxides Co₃O₄,V₂O₅,Cr₂O₃ with d orbital active centers and six kinds of metal oxides Mo O₃,Nb₂O₅,WO₃,Ta₂O₅,Zr O₂,Ti O₂ with no d-orbital active centers through literature research,and use B The cellulose-based film forming method coats these metal oxide powder materials without any morphology control on the surface of FTO to prepare an anode electrode for electrocatalytic water splitting,and initially electrochemically these materials in Na₂SO₄electrolyte The characterization of performance and the quantitative determination of hydrogen peroxide in the anolyte show that the metal oxide without the active center of d orbital has obvious 2e-WOR activity.（2）In order to further explore the selectivity of the six metal oxides 2e-WOR without d orbital active centers,on the basis of the previous chapter,change the cations and anions of the electrolyte,and compare these in different anion and cation electrolytes.The material was characterized by electrochemical performance and quantitative determination of hydrogen peroxide to further verify that metal oxides without d orbital active centers have 2e-WOR selectivity,and explore the possible influence of different anions and cations on the 2e-WOR selectivity of these metal oxides.After testing,in different anion and cation electrolytes,these metal oxides without d orbital active centers all show different degrees of 2e-WOR selectivity,and in CH₃COONa electrolyte,Mo O₃ materials show the best 2e-WOR optional.Further,explore the influence of CH₃COONa electrolytes of different p H on the selectivity of different metal oxides 2e-WOR,and oxidize these six metals in the CH₃COONa electrolytes of p H=5,p H=7,p H=8,and p H=10.5.The characterization of the electrochemical performance and the quantitative detection of hydrogen peroxide were carried out.It is found that the 2e-WOR selectivity of metal oxides in alkaline CH₃COONa electrolyte is better than that of acidic CH₃COONa electrolyte,but the selectivity of metal oxide 2e-WOR will decrease to a certain extent when the p H value of alkaline electrolyte is higher.