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| The promoting mechanism of Cu doping on the gas-sensing response of SnO2 |
| HOU Haiyun1, XU Jiale1, ZHANG Haojie1, ZHANG Zinan1, ZHANG Enkang2, LIU Songtao2 |
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 |
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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.
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Received: 08 June 2026
Published: 12 November 2026
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[1] KULKARNI S N, LOKANATH N K.Advances in SnO2 based S-scheme heterojunctions for photocatalytic energy conversion and environmental remediation[J]. Solar Energy, 2026, 315: 114758. [2] 陈思璐, 李丽, 雷霆. Nb掺杂SnO2负载RuO2酸性析氧催化剂的制备和性能[J]. 粉末冶金材料科学与工程, 2026, 31(3): 297-309. CHEN Silu, LI Li, LEI Ting.Preparation and performance of Nb-doped SnO2 supported RuO2 acidic oxygen evolution catalysts[J]. Materials Science and Engineerying of Powder Metallurgy, 2026, 31(3): 297-309. [3] GAO C B, SONG X Q, CHENG T T, et al.Review: modulation preparation and performance optimization of one-dimensional SnO2 gas sensitive nanomaterials[J]. Journal of Materials Science, 2026, 61(19): 12967-12994. [4] SU Z J, DU P, HOU W, et al.Synthesis, characterization, and gas-sensitive properties of SnO/SnO2 core-shell homojunction by vapor-oxidate-solid process[J]. Applied Surface Science, 2025, 712: 164231. [5] SNEHA C, VARGHESE S.Nickel-sensitized Sb: SnO2 thin films for enhanced room temperature hydrogen gas sensing[J]. Surfaces and Interfaces, 2025, 64: 106352. [6] HUNG N P, QUAN T N A, TIEN L T, et al. Enhanced ammonia sensing using Pt-decorated single-crystalline SnO2 nanowires prepared by sputtering[J]. RSC Advances, 2026, 16(18): 16694-16702. [7] SHAHNAZARYAN G, ALEKSANYAN M, SAYUNTS A, et al.Study of a nanostructured Co-doped SnO2 sensor for hydrogen peroxide vapor detection using impedance spectroscopy[J]. ACS Omega, 2025, 10(14): 14452-14465. [8] LI J Q, ZHAO X, LI D, et al.Innovative bifunctional SnO2:La3+//CeO2:Eu3+ Janus nanofibers sensor: exceptional n-butanol gas-sensitive with red fluorescent properties for convenient detection of sensing films breakage[J]. Sensors and Actuators B: Chemical, 2025, 442: 138173. [9] BOROUN Z, GHORBANI M, MOHAMMADPOUR R, et al.Origin of working temperature in H2S sensing process of SnO2-CuO thin bilayer: a theoretical macroscopic approach[J]. Sensors and Actuators B: Chemical, 2017, 252: 944-950. [10] LIU J Q, LU Y T, CUI X, et al.Gas-sensing properties and sensitivity promoting mechanism of Cu-added SnO2 thin films deposited by ultrasonic spray pyrolysis[J]. Sensors and Actuators B: Chemical, 2017, 248: 862-867. [11] ZHANG G, LIU M L.Effect of particle size and dopant on properties of SnO2-based gas sensors[J]. Sensors and Actuators B: Chemical, 2000, 69(1/2): 144-152. [12] WANG C X, ZENG W, LUO L J, et al.Gas-sensing properties and mechanisms of Cu-doped SnO2 spheres towards H2S[J]. Ceramics International, 2016, 42(8): 10006-10013. [13] REN F M, GAO L P, YUAN Y W, et al.Enhanced BTEX gas-sensing performance of CuO/SnO2 composite[J]. Sensors and Actuators B: Chemical, 2016, 223: 914-920. [14] BABU B, KADAM A N, RAVIKUMAR R V S S N, et al. Enhanced visible light photocatalytic activity of Cu-doped SnO2 quantum dots by solution combustion synthesis[J]. Journal of Alloys and Compounds, 2017, 703: 330-336. [15] LIU S T, SUN Q Y, WANG J B, et al.Charge imbalance induced oxygen-adsorption enhances the gas-sensing properties of Al-doped SnO2 powders[J]. Journal of Physics and Chemistry of Solids, 2019, 124: 163-168. [16] XI L J, QIAN D, HUANG X H, et al.Fine nanoparticles of Al-SnO2 prepared by a co-precipitation route in water/oil microemulsion[J]. Journal of Alloys and Compounds, 2008, 462(1/2): 42-46. [17] KIRSZENSZTEJN P, SZYMKOWIAK A.Thermal analysis of binary system Al2O3-SnO2 obtained by sol-gel technique[J]. Journal of Thermal Analysis and Calorimetry, 2005, 81(1): 35-39. [18] FUJIHARA S, MAEDA T, OHGI H, et al.Hydrothermal routes to prepare nanocrystalline mesoporous SnO2 having high thermal stability[J]. Langmuir, 2004, 20(15): 6476-6481. [19] CHEN A Q, XIA S J, JI Z G, et al.Effects of Cu doping on the structure, electronic and optical properties of SnO2 thin films by spray pyrolysis: an experimental and density functional study[J]. Surface and Coatings Technology, 2017, 322: 120-126. [20] CHETRI P, SAIKIA B, CHOUDHURY A.Structural and optical properties of Cu doped SnO2 nanoparticles: an experimental and density functional study[J]. Journal of Applied Physics, 2013, 113(23): 233514. [21] NILAVAZHAGAN S, MUTHUKUMARAN S, ASHOKKUMAR M.Structural, optical and morphological properties of La, Cu co-doped SnO2 nanocrystals by co-precipitation method[J]. Optical Materials, 2014, 37: 425-432. [22] GALDIKAS A, JASUTIS V, KAČIULIS S, et al. Peculiarities of surface doping with Cu in SnO2 thin film gas sensors[J]. Sensors and Actuators B: Chemical, 1997, 43(1/2/3): 140-146. [23] CHETRI P, CHOUDHURY A.Investigation of structural and magnetic properties of nanoscale Cu doped SnO2: an experimental and density functional study[J]. Journal of Alloys and Compounds, 2015, 627: 261-267. [24] GAO Y, ZHAO H B, ZHAO B Y.Monolayer dispersion of oxide additives on SnO2 and their promoting effects on thermal stability of SnO2 ultrafine particles[J]. Journal of Materials Science, 2000, 35(4): 917-923. [25] KOCEMBA I, RYNKOWSKI J M.The effect of oxygen adsorption on catalytic activity of SnO2 in CO oxidation[J]. Catalysis Today, 2011, 169(1): 192-199. [26] CHANG S C.Oxygen chemisorption on tin oxide: correlation between electrical conductivity and EPR measurements[J]. Journal of Vacuum Science and Technology, 1980, 17(1): 366-369. [27] CHOWDHURI A, GUPTA V, SREENIVAS K.Fast response H2S gas sensing characteristics with ultra-thin CuO islands on sputtered SnO2[J]. Sensors and Actuators B: Chemical, 2003, 93(1/2/3): 572-579. |
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