Synthesis And Gas Sensing Properties Of C?N?Pt Co-Doped Mesoporous ZnO And Composite ZnO Nanostructures

With the rapid development of nanotechnology and the maturity of the preparation process,ZnO-based gas sensors have received widespread attention.How to enhance the performance of the sensors has become a research hotspot in this field.In this paper,three kinds of ZnO nanocomposite structures were synthesized using metal-organic framework ZIF-8 as a precursor,and their gas-sensitive properties were tested,respectively,and the corresponding gas-sensitive properties mechanism was further analyzed.The following research results have been achieved:1.C,N,Pt co-doped mesoporous zinc oxide was synthesized by a simple two-step method,and its morphology and structure were characterized.The results showed that the synthesized C,N,Pt-ZnO nanocomposite structure was uniform in size and dispersibility.better.The C,N,Pt-ZnO gas sensor was prepared and its gas sensing performance was studied.The results show that C,N,Pt-ZnO shows high sensitivity to dimethylamine gas at the optimal working temperature of 160?,reaching 1200,which is 4.3 times that of pure ZnO under the same conditions.The C,N,Pt-ZnO nanocomposite structure's high response to dimethylamine gas originates from large specific surface area,rich mesopores,high inherent defect content,and characteristic small size,while short response recovery time benefits from embedding A large number of mesopores in ZnO nanosheets.2.CeO₂-ZnO nanocomposite structure was synthesized by a simple two-step method,and its morphology and structure were characterized.The results show that the synthesized CeO₂-ZnO nanocomposite structure is uniform in size and has good dispersibility.By preparing CeO₂-ZnO gas sensor,its gas sensing performance was studied.The results show that CeO₂-ZnO exhibits high sensitivity to dimethylamine gas,fast response recovery and good selectivity at the optimal working temperature of240?.This phenomenon is caused by the formation of heterojunctions and the synergy of defects and high specific surface area.3.The Sn O₂-ZnO nanocomposite structure was synthesized by a simple two-step method,and its morphology and structure were characterized.The Sn O₂-ZnO gas sensor was prepared and its gas sensing performance was studied.The results show that Sn O₂-ZnO exhibits higher sensitivity to dimethylamine gas at 160?optimum operating temperature,fast response recovery and good selectivity.This phenomenon is caused by the formation of heterojunctions and the synergy of defects and high specific surface area.