Preparation And Photocatalytic Activity Of Zinc Oxide And Silver Compounds Composites

Semiconductor photocatalysts are widely used in photocatalytic degradation materials due to their high catalytic activity and stability.In this paper,the photocatalyst with composite structure based on ZnO/Ag compound was designed and prepared to expand the light absorption range and improve the effective carrier separation,so as to enhance the activity of the photocatalyst.The details are as follows:1.ZnO nanorods with a length of 1.8μm and a diameter of 30 nm were prepared by hydrothermal method.Ag₂S were grown on the surface of ZnO by ion layer deposition.The illumination during the experiment caused the Ag⁺adsorbed on the surface of ZnO to be reduced to form Ag nanoparticles,and finally formed a ZnO/Ag/Ag₂S heterojunction structure.The amount of Ag₂S and Ag on ZnO surface was controlled by controlling the deposition times of ion layer.The heterostructure of ZnO/Ag/Ag₂S,which has been deposited and grown for 6 times in the ionic layer,has the highest photocatalytic efficiency.The degradation rate of20 mL 2.5 ppm methylene blue solution within 100 min reaches 94.41%,the catalytic efficiency is 2.6 times that of pure ZnO nanorods.The narrow band gap of Ag₂S and the LSPR effect of Ag broaden the light absorption range of photocatalyst and improve the light absorption efficiency.In ZnO/Ag/Ag₂S z-shaped heterostructure structure,Ag compounds the electron holes with lower activity,leaving the electron holes with higher activity to participate in photocatalytic reaction,thereby improving the photocatalytic efficiency of the material.Prepare ZnO/Ag materials,thus,the photocatalytic efficiency of the material was improved.ZnO/Ag materials were used as contrast materials to prove the absorption of the composite is enhanced by surface plasmon resonance.the degradation rate of the ZnO/Ag composite to the2.5 ppm methylene blue solution reached 99.38%within 70 min.2.The photocatalytic properties of CC（Carbon Cloth）/ZnO/Ag/AgCl materials were prepared and studied.ZnO nanorods were prepared on carbon cloth by hydrothermal method,and AgCl was grown on ZnO surface by ion layer deposition method.The results show that When the number of AgCl growth and deposition was 12 times,the photocatalytic degradation efficiency of the material is the best.In 90 min,the concentration of the 20 mL 10ppm methylene blue solution is 99%.In addition,a single CC/Ag/AgCl structure was prepared for comparison.When AgCl was grown for 30 times,the photocatalytic effect was the best,and the degradation efficiency of 20 mL 10 ppm methylene blue solution within 90minutes was 97.42%.Contrast experiments show that ZnO enhances the carrier transport performance of the heterostructure material,improves the carrier separation efficiency,and further enhances the photocatalytic ability of the material.The high conductivity of carbon cloth improves the carrier transport rate.ZnO/Ag/AgCl forms z-type heterojunction structure,which enhances the light absorption of the material,inhibits the composite of electron hole pairs in a single material,promotes the carrier separation,and improves the catalytic activity.3.The properties of CC/ZnO/Ag₂CO₃/Ag materials were studied.By means of ion layer deposition,Ag₂CO₃ particles were prepared on ZnO nanorods to form CC/ZnO/Ag₂CO₃/Ag composite structureWhen the deposition times were 30 times,the photocatalytic efficiency of the sample was the best.Within 60 minutes,20 mL of 10 ppm methylene blue solution was completely degraded The experiment proved that Ag₂CO₃ micron particles did not form a good heterostructure with ZnO nanorods,and ZnO only played a supporting role and failed to effectively participate in the photocatalytic reaction.In the heterogeneous structure of Ag₂CO₃/Ag,the light absorption efficiency of Ag nanomaterials was improved by LSPR effect Ag₂CO₃/Ag heterostructure effectively inhibits the combination of photogenic electron-hole pairs.The size and content of Ag₂CO₃ have the largest impact on the catalytic efficiency.The smaller particles ensure a higher specific surface area,so higher photocatalytic efficiency can be obtained.