1. School of Environmental & Chemical Engineering, Xi’an Polytechnic University, Xi’an 710048, China; 2. School of Materials Science & Engineering, Xi’an Polytechnic University, Xi’an 710048, China
Abstract：To determine the main influence mechanism of Cu doping on the gas-sensing performance of SnO2, SnO2, Cu-doped SnO2, and CuO powders were prepared by the sol-gel method, and the gas-sensing response of Cu-doped SnO2 to ethanol gas was systematically studied. The results show that when the molar ratio of Cu/Sn is 0-0.15, the gas-sensing response degree of Cu-doped SnO2 to ethanol gas slightly increases with the increase of Cu-doping content. When the molar ratio of Cu/Sn reaches 0.18, the gas-sensing response degree of Cu-doped SnO2 to ethanol gas shows a sudden increase and reaches its maximum value. Continuing to increase the molar ratio of Cu/Sn, the gas-sensing response degree of Cu-doped SnO2 to ethanol gas decreases. When the molar ratio of Cu/Sn is 0-0.15, Cu2+ replaces Sn4+ in the SnO2 lattice to form a solid solution, increasing the oxygen vacancies on the surface of SnO2 grains and thereby slightly improving the gas-sensing response of SnO2. When the molar ratio of Cu/Sn reaches 0.15, the solid solubility of Cu2+ in the SnO2 lattice reaches its maximum. Continuing to increase the Cu-doping content, excess Cu2+ adhere to the surface of SnO2 grains to form CuO quantum dots, catalyzing the reaction between SnO2 and ethanol gas, thereby greatly improving the gas-sensing response of SnO2. This is the main reason why Cu-doping promotes the gas-sensing response of SnO2.
侯海云, 徐佳乐, 张豪杰, 张子楠, 张恩康, 刘松涛. Cu掺杂对SnO2气敏响应的促进机制[J]. 粉末冶金材料科学与工程, 2026, 31(5): 557-564.
HOU Haiyun, XU Jiale, ZHANG Haojie, ZHANG Zinan, ZHANG Enkang, LIU Songtao. The promoting mechanism of Cu doping on the gas-sensing response of SnO2[J]. Materials Science and Engineering of Powder Metallurgy, 2026, 31(5): 557-564.
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2026, Vol. 31 
