Preparation Of Ag-based Nanocomposites And Photoelectric Catalysis

Research and development of semiconductor catalysts is an effective way to solve energy shortages and environmental pollution.In recent years,Ag-based composite materials have achieved excellent results in the fields of photocatalysis and electrocatalysis.In this paper,g-C₃N₄/Co₃O₄/Ag₂O ternary nanocomposite and Ag₈W₄O?16?/CoWO₄ binary nanocomposite were successfully prepared,and the composites were characterized by XRD,TEM,SEM,XPS etc.The photocatalytic degradation of pollutants in water and electrochemical oxygen reduction performance of g-C₃N₄/Co₃O₄/Ag₂O ternary nanocomposites and the electrocatalytic water splitting performance of Ag₈W₄O?16?/CoWO₄ binary nanocomposites were studied.The main research contents of this paper are as follows:1.In this paper,a ternary heterojunction nanocomposite g-C₃N₄/Co₃O₄/Ag₂O was successfully prepared,and their morphology,structure and composition were analyzed by TEM,EDS,XRD,XPS and BET.The photocatalytic performance of Rh B was studied through photocatalytic degradation experiments.It was proved that the ternary compound g-C₃N₄/Co₃O₄/Ag₂O has higher photodegradation efficiency?98.09%?than other compounds after 1 h of visible light irradiation,and the impact of AgNO₃ was explored on the photocatalytic performance.2.The mechanism of photodegradation of Rh B was explored by free radical capture,oxygen reduction,and detection of H₂O₂.Free radical capture experiments look for the main active substances in the photocatalytic process.Electrochemical oxygen reduction?ORR?experiments show that the electron transfer value of g-C₃N₄/Co₃O₄/Ag₂O is 2.07,which promotes the reduction reaction of O₂ to generate H₂O₂.The DPD-POD method further proves that H₂O₂ will be generated during the photocatalytic process,and the addition of Ag₂O will increase the production of H₂O₂.Based on the above results,a possible photocatalytic reaction mechanism was proposed.3.Ag₈W₄O?16?/CoWO₄ binary nanocomposite was successfully prepared by hydrothermal synthesis,and characterized by XRD,SEM,XPS.In addition,HER experiments were performed in acid electrolytes,and OER experiments were performed in neutral electrolytes and alkaline electrolytes.The experiment result shows that Ag₈W₄O₁₆ is more conducive to the HER reaction in acid electrolyte,and CoWO₄ is more conducive to the OER reaction in alkaline electrolyte.