Catalytic Decomposition Of Ozone On M/g-?O?C₃N₄?M=Co,Cu,Mn?

O₃ is a widely used oxidant and a common by-product in industrial production.O₃ in the human environment will harm human health and ecosystems,and will react with organic matter to form secondary pollutants such as aldehydes,acids and ultrafine particles.At present,catalytic decomposition is a method for eliminating O₃,which mainly focuses on metal oxide catalysts.Its catalytic action depends on the oxygen vacancies on the surface of the catalyst.When oxygen occupies oxygen vacancies and is difficult to eliminate,the catalyst is deactivated.The regeneration of deactivated catalyst requires the use of hydrogen reduction under high temperature conditions,so it is urgent to develop a catalyst that can overcome the above shortcomings.The two-dimensional material g-C₃N₄ has a 3-s-triazine ring structure.There are six N atoms in the ring that can coordinate with metal atoms.These coordination bonds can fix metal atoms and efficiently disperse metal atoms.It is stable and uniform for synthesis.The catalyst provides the possibility;metal atoms can be exposed on the surface of g-C₃N₄,increasing the effective contact between metal atoms and O₃;the number and method of coordination between metal atoms and N atoms can be used to affect the catalytic process and regeneration method of decomposing O₃.In this study,g-C₃N₄ supported Co sub-nano clusters,g-C₃N₄ and O-substituted g-OC₃N₄supported single-atom Mn and Cu catalysts were prepared by impregnation reduction method.The structure and properties of the catalysts were analyzed by XRD,BET,TEM,XPS,and their performance in decomposing O₃ was evaluated.Combined with density functional theory calculation,the stable adsorption structure of sub-nano Co_x?x=1-4?clusters on g-C₃N₄ and the stability of ozone on Co_x/g-C₃N₄?x=1-4?are given.Adsorption configuration;the mechanism of single atom catalyst M/g-?O?C₃N₄?M=Cu,Mn?for catalytic decomposition of ozone.Studies have shown that g-C₃N₄ and g-OC₃N₄ supported metal Co,Mn,Cu catalysts,metal loading methods and carrier doping can significantly affect the catalyst's ozone decomposition activity.Low loading Co/g-C₃N₄,Co exists as amorphous sub-nano particles,when decomposing O₃,Co generates amorphous oxide,does not depend on lattice O vacancy decomposition O₃,can be heated by low temperature Regeneration catalyst.Compared with Cu/g-C₃N₄,single-atom-supported Cu/g-OC₃N₄,doped O changes the coordination mode of Cu and N in the process of ozone decomposition,and improves the efficiency of the catalyst.Monoatomic Mn/g-C₃N₄ and Mn/g-OC₃N₄,by changing the number of Mn-N and Mn-O coordination bonds and coordination mode,to achieve the purpose of efficient decomposition of O₃,to avoid dependence on oxygen vacancies.In this experiment,a series quartz tube reactor was used as the catalytic device,and the catalyst was mixed and filled with quartz sand.When the O₃ concentration is 40ppm,the relative humidity is¹%,and the space velocity is 600L?L^-1?h^-1,the prepared Mn/g-C₃N₄and Cu/g-OC₃N₄ can be operated continuously for 1 day,and the activity still reaches 100%.