SnO2 nanostructured materials used as gas sensors for the detection of hazardous and flammable gases: A review

Zhang, 2020, Characterizing the toxic gaseous emissions of gasoline and diesel vehicles based on a real-world on-road investigation, J. Clean. Prod., 124957 Song, 2020, Comparative study of methanol gas sensing performance for SnO2 nanostructures by changing their morphology, Mater. Sci. Semicond. Process., 111, 104986, 10.1016/j.mssp.2020.104986 Zhang, 2020, Influence of green plants on indoor harmful gases, Heilongjiang Agricultural Sciences, 6, 68 Kar, 2014, Recent development of core–shell SnO2 nanostructures and their potential applications, J. Mater. Chem. C, 2, 6706, 10.1039/C4TC01030B Pang, 2018, The impacts of water vapour and co-pollutants on the performance of electrochemical gas sensors used for air quality monitoring, Sensor. Actuator. B Chem., 266, 674, 10.1016/j.snb.2018.03.144 Sun, 2012, Metal oxide nanostructures and their gas sensing properties: a review, Sensors, 12, 2610, 10.3390/s120302610 Qing, 2019, Development of a multi-component infrared gas sensor detection system, J. Phys. Conf., 1229 Hodgkinson, 2013, Optical gas sensing: a review, Meas. Sci. Technol., 24, 10.1088/0957-0233/24/1/012004 Tang, 2016, Enhanced gas sensing mechanisms of metal oxide heterojunction gas sensors, Acta Phys. Chim. Sin., 32, 1087, 10.3866/PKU.WHXB201602224 Yan, 1995, Preparation, structure and gas sensing properties of Fe2O3 thin films, Journal of Electronics & Information Technollgy, 17, 506 Moon, 2004, Selective gas detection of SnO2-TiO2 gas sensors, J. Electroceram., 13, 707, 10.1007/s10832-004-5180-1 Chen, 2015, Gas sensing properties of ZnO-SnO2 nanostructures, J. Nanosci. Nanotechnol., 15, 1245, 10.1166/jnn.2015.9061 Patil, 2009, Cr2O3-modified ZnO thick film resistors as LPG sensors, Talanta, 77, 1409, 10.1016/j.talanta.2008.09.038 Yu, 2015, Facile synthesis of α-Fe2O3@SnO2 core-shell heterostructure nanotubes for high performance gas sensors, Sensor. Actuator. B Chem., 213, 27, 10.1016/j.snb.2015.01.130 Das, 2014, A comprehensive review on structures and gas sensors, Prog. Mater. Sci., 66, 112, 10.1016/j.pmatsci.2014.06.003 Gracia, 2007, Characterization of the high-pressure structures and phase transformations in SnO2, a density functional theory study, J. Phys. Chem. B, 111, 6479, 10.1021/jp067443v Errico, 2007, Ab initio FP-LAPW study of the semiconductors SnO and SnO2, Physica B Physics of Condensed Matter, 389, 140, 10.1016/j.physb.2006.07.041 Xu, 2009, First principle study on the electronic structure of fluorine-doped SnO2, Solid State Commun., 149, 527, 10.1016/j.ssc.2009.01.010 Liu, 2012, A survey on gas sensing technology, Sensors, 12, 9635, 10.3390/s120709635 Liu, 2015, Nanoparticle cluster gas sensor: Pt activated SnO2 nanoparticles for NH3 detection with ultrahigh sensitivity, Nanoscale, 7, 14872, 10.1039/C5NR03585F Rawal, 2014, Facial synthesis of hexagonal metal oxide nanoparticles for low temperature ammonia gas sensing applications, RSC Adv., 5, 4135, 10.1039/C4RA12747A Wang, 2008, Fabrication of a SnO2 nanowire gas sensor and sensor performance for hydrogen, J. Phys. Chem. C, 112, 6643, 10.1021/jp8003147 Huang, 2010, Pt surface modification of SnO2 nanorod arrays for CO and H2 sensors, Nanoscale, 2, 1203, 10.1039/c0nr00159g Chen, 2017, Promotion on acetone sensing of single SnO2 nanobelt by Eu doping, Nanoscale Research Letters, 12, 405, 10.1186/s11671-017-2177-7 Hahn, 2003, CO sensing with SnO2 thick film sensors: role of oxygen and water vapour, Thin Solid Films, 436, 17, 10.1016/S0040-6090(03)00520-0 Stefanov, 2008, Preparation and characterization of SnO2 films for sensing applications, J. Phys. Conf., 100 Wu, 2013, Hydrothermal synthesis of novel SnO2 nanoflowers and their gas-sensing properties, Mater. Lett., 104, 34, 10.1016/j.matlet.2013.04.010 Wang, 2004, Mesostructured SnO2 as sensing material for gas sensors, Solid State Electron., 85, 627, 10.1016/j.sse.2003.09.015 Jin, 2015, Synthesis of hierarchical SnO2 nanoflowers with enhanced acetic acid gas sensing properties, Appl. Surf. Sci., 353, 71, 10.1016/j.apsusc.2015.06.089 Wei, 2015, Template-free synthesis of flower-like SnO2 hierarchical nanostructures with improved gas sensing performance, Sensor. Actuator. B Chem., 215, 15, 10.1016/j.snb.2015.03.042 Xu, 2020, Highly sensitive and selective electronic sensor based on Co catalyzed SnO2 nanospheres for acetone detection, Sensor. Actuator. B Chem., 304, 127237, 10.1016/j.snb.2019.127237 Wang, 2011, Facile synthesis of hierarchical SnO2 semiconductor microspheres for gas sensor application, Sensor. Actuator. B Chem., 155, 285, 10.1016/j.snb.2010.12.036 Li, 2010, Enhanced gas sensing by assembling Pd nanoparticles onto the surface of SnO2 nanowires, Talanta, 82, 458, 10.1016/j.talanta.2010.04.053 Katti, 2003, Mechanism of drifts in H2S sensing properties of SnO2:CuO composite thin film sensors prepared by thermal evaporation, Sensor. Actuator. B Chem., 96, 245, 10.1016/S0925-4005(03)00532-X Kim, 2006, SnO2 microparticles by thermal evaporation and their properties, Ceram. Int., 32, 943, 10.1016/j.ceramint.2005.06.015 Shukla, 2004, Room temperature hydrogen gas sensitivity of nanocrystalline pure tin oxide, J. Nanosci. Nanotechnol., 4, 141, 10.1166/jnn.2004.022 Shao, 2013, Heterostructured p-CuO (nanoparticle)/n-SnO2 (nanowire) devices for selective H2S detection, Sensor. Actuator. B Chem., 181, 130, 10.1016/j.snb.2013.01.067 Wang, 2010, Improved hydrogen monitoring properties based on p-NiO/n-SnO2 heterojunction composite nanofibers, J. Phys. Chem. C, 114, 6100, 10.1021/jp9100202 Fan, 2019, UV-enhanced NO2 gas sensor based on electrospinning SnO2-ZnO composite nanofibers, IOP Conf. Ser. Mater. Sci. Eng., 479, 10.1088/1757-899X/479/1/012121 Lupan, 2009, A rapid hydrothermal synthesis of rutile SnO2 nanowires, Mater. Sci. Eng., B, 157, 101, 10.1016/j.mseb.2008.12.035 Lin, 2012, Tin oxide/graphene composite fabricated via a hydrothermal method for gas sensors working at room temperature, Sensor. Actuator. B Chem., 173, 139, 10.1016/j.snb.2012.06.055 Cheng, 2016, A review of recent developments in tin dioxide composites for gas sensing application, J. Ind. Eng. Chem., 44, 1, 10.1016/j.jiec.2016.08.008 Liu, 2010, Novel sea urchin-like hollow core–shell SnO2 superstructures: facile synthesis and excellent ethanol sensing performance, Sensor. Actuator. B Chem., 151, 229, 10.1016/j.snb.2010.09.015 Chen, 2011, Nanowires assembled SnO2 nanopolyhedrons with enhanced gas sensing properties, ACS Appl. Mater. Interfaces, 3, 2112, 10.1021/am2003312 Sun, 2015, Hierarchical assembly of α-Fe2O3 nanosheets on SnO2 hollow nanospheres with enhanced ethanol sensing properties, ACS Appl. Mater. Interfaces, 7, 19119, 10.1021/acsami.5b04751 Lin, 2015, Preparation of Pd nanoparticle-decorated hollow SnO2 nanofibers and their enhanced formaldehyde sensing properties, J. Alloys Compd., 651, 690, 10.1016/j.jallcom.2015.08.174 Li, 2014, Preparation of Pr-doped SnO2 hollow nanofibers by electrospinning method and their gas sensing properties, J. Alloys Compd., 605, 80, 10.1016/j.jallcom.2014.03.182 Wang, 2015, Preparation of Yb-doped SnO2 hollow nanofibers with an enhanced ethanol–gas sensing performance by electrospinning, Sensor. Actuator. B Chem., 216, 212, 10.1016/j.snb.2015.04.040 Wang, 2020, SnO2 microrods based triethylamine gas sensor, IOP Conf. Ser. Mater. Sci. Eng., 772, 10.1088/1757-899X/772/1/012058 Ying, 2004, SnO2 nanowhiskers and their ethanol sensing characteristics, Nanotechnology, 15, 1682, 10.1088/0957-4484/15/11/053 Wang, 2010, Metal oxide gas sensors: sensitivity and influencing factors, Sensors, 10, 2088, 10.3390/s100302088 Shukla, 2004, Room temperature hydrogen gas sensitivity of nanocrystalline pure tin oxide, Nanosci. Nanotechnol., 4, 141, 10.1166/jnn.2004.022 Ebrahimi, 2012, Selective deposition of CuO/SnO2 sol–gel on porous SiO2 suitable for the fabrication of MEMS-based H2S sensors, Sensor. Actuator. B Chem., 173, 802, 10.1016/j.snb.2012.07.104 Stoycheva, 2011, Aerosol-assisted CVD of SnO2 thin films for gas-sensor applications, Chem. Vap. Depos., 17, 247, 10.1002/cvde.201106917 Liu, 2013, Aerosol-assisted CVD of SnO2 thin films for the room-temperature detection of hydrogen sulfide, Key Eng. Mater., 543, 422, 10.4028/www.scientific.net/KEM.543.422 Nakate, 2017, Gold sensitized sprayed SnO2 nanostructured film for enhanced LPG sensing, J. Anal. Appl. Pyrol., 124, 362, 10.1016/j.jaap.2016.12.029 Krishnan, 2017, Surfactant modified SnO2 nanostructured thin film for improved sensing performance of LPG and ammonia, AIP Conference Proceedings, 1832 Ma, 2013, Enhanced ethanol sensing properties of ZnO-doped porous SnO2 hollow nanospheres, Sensor. Actuator. B Chem., 188, 193, 10.1016/j.snb.2013.06.099 Liu, 2017, Highly sensitive and low detection limit of ethanol gas sensor based on hollow ZnO/SnO2 spheres composite material, Sensor. Actuator. B Chem., 245, 551, 10.1016/j.snb.2017.01.148 Hu, 2003, A room temperature indium tin oxide/quartz crystal microbalance gas sensor for nitric oxide, Sensor. Actuator. B Chem., 93, 175, 10.1016/S0925-4005(03)00186-2 Dong, 2014, Combustion synthesis of porous Pt-functionalized SnO2 sheets for isopropanol gas detection with a significant enhancement in response, J. Mater. Chem., 2 Cai, 2020, Synthesis of Pd nanoparticle-decorated SnO2 nanowires and determination of the optimum quantity of Pd nanoparticles for highly sensitive and selective hydrogen gas sensor, Sensor. Actuator. B Chem., 322, 128651, 10.1016/j.snb.2020.128651 Yao, 2020, A high sensitivity and selectivity n-butanol sensor based on monodispersed Pd-doped SnO2 nanoparticles mediated by glucose carbonization, Semicond. Sci. Technol., 35, 10.1088/1361-6641/ab9d08 Sun, 2020, Synthesis and room-temperature H2S sensing of Pt nanoparticle-functionalized SnO2 mesoporous nanoflowers, J. Alloys Compd., 842, 155813, 10.1016/j.jallcom.2020.155813 Quan, 2020, A highly sensitive and selective ppb-level acetone sensor based on a Pt-doped 3D porous SnO2 hierarchical structure, Sensors, 20, 1150, 10.3390/s20041150 Wang, 2020, SnO2 core-shell hollow microspheres co-modification with Au and NiO nanoparticles for acetone gas sensing, Powder Technol., 364, 159, 10.1016/j.powtec.2020.02.006 Fedorenko, 2020, Cerium-doped SnO2 nanomaterials with enhanced gas-sensitive properties for adsorption semiconductor sensors intended to detect low H2 concentrations, J. Mater. Sci., 55, 16612, 10.1007/s10853-020-05199-w Xu, 2017, Fabrication of Pr-doped SnO2 spherical core-shell nanostructure with wrinkly shell and the gas sensing properties, Mater. Lett., 195, 159, 10.1016/j.matlet.2017.02.104 Sohal, 2021, Modification of SnO2 surface oxygen vacancies through Er doping for ultralow NO2 detection, Mater. Res. Bull., 133, 111051, 10.1016/j.materresbull.2020.111051 Zhao, 2020, Ultrasensitive SO2 sensor for sub-ppm detection using Cu-doped SnO2 nanosheet arrays directly grown on chip, Sensor. Actuator. B Chem., 324, 128745, 10.1016/j.snb.2020.128745 Shen, 2009, Microstructure and H2 gas sensing properties of undoped and Pd-doped SnO2 nanowires, Sensor. Actuator. B Chem., 135, 524, 10.1016/j.snb.2008.09.010 Chen, 2013, Pd-doped SnO2-based sensor detecting characteristic fault hydrocarbon gases in transformer oil, J. Nanomater., 1, 2527 Li, 2017, Pd nanoparticles composited SnO2 microspheres as sensing materials for gas sensors with enhanced hydrogen response performances, J. Alloys Compd., 710, 216, 10.1016/j.jallcom.2017.03.274 Zhao, 2019, ‘Green’ prepare SnO2 nanofibers by shaddock peels: application for detection of volatile organic compound gases, J. Mater. Sci. Mater. Electron., 30, 3032, 10.1007/s10854-018-00582-5 Zhao, 2018, Pd-functionalized SnO₂ nanofibers prepared by shaddock peels as bio-templates for high gas sensing performance toward butane, Nanomaterials, 9, 13, 10.3390/nano9010013 Dong, 2018, Nonaqueous synthesis of Pd-functionalized SnO2/In2O3 nanocomposites for excellent butane sensing properties, Sensor. Actuator. B Chem., 257, 419, 10.1016/j.snb.2017.10.175 Dong, 2011, Enhanced H2S sensing characteristics of Pt doped SnO2 nanofibers sensors with micro heater, Sensor. Actuator. B Chem., 157, 154, 10.1016/j.snb.2011.03.043 Peng, 2019, Pt decorated SnO2 nanoparticles for high response CO gas sensor under the low operating temperature, J. Mater. Sci. Mater. Electron., 30, 3921, 10.1007/s10854-019-00677-7 Li, 2016, Enhanced methanol sensing properties of SnO2 microspheres in a composite with Pt nanoparticles, RSC Adv., 6, 83870, 10.1039/C6RA16636A Song, 2012, Preparation, characterization and acetone sensing properties of Ce-doped SnO2 hollow spheres, Sensor. Actuator. B Chem., 173, 839, 10.1016/j.snb.2012.07.115 Jin, 2015, One-step synthesis and highly gas-sensing properties of hierarchical Cu-doped SnO2 nanoflowers, Sensor. Actuator. B Chem., 213, 171, 10.1016/j.snb.2015.02.075 Zhao, 2020, Shaddock peels as bio-templates synthesis of Cd-doped SnO2 nanofibers: a high performance formaldehyde sensing material, J. Alloys Compd., 813, 152170, 10.1016/j.jallcom.2019.152170 Xu, 2020, Nanostructured of SnO2/NiO composite as a highly selective formaldehyde gas sensor, J. Mater. Res., 35, 3079, 10.1557/jmr.2020.239 Din, 2020, Development of high-performance sensor based on NiO/SnO2 heterostructures to study sensing properties towards various reducing gases, Nanotechnology, 31, 10.1088/1361-6528/ab98bb Zhu, 2020, Hierarchical highly ordered SnO2 nanobowl branched ZnO nanowires for ultrasensitive and selective hydrogen sulfide gas sensing, Microsystems & Nanoengineering, 6, 30, 10.1038/s41378-020-0142-6 Zhao, 2020, Construction of ZnO–SnO2 n-n junction for dual-sensing of nitrogen dioxide and ethanol, Vacuum, 181, 109615, 10.1016/j.vacuum.2020.109615 Leangtanom, 2020, Highly sensitive and selective ethylene gas sensors based on CeOx-SnO2 nanocomposites prepared by a Co-precipitation method, Mater. Chem. Phys., 254, 123540, 10.1016/j.matchemphys.2020.123540 Mou, 2020, Low-temperature hydrogen detection sensor based on CeO2-doped SnO2, J. Mater. Sci. Mater. Electron., 31, 15785, 10.1007/s10854-020-04141-9 Li, 2020, Electrospun TiO2/SnO2 Janus nanofibers and its application in ethanol sensing, Mater. Lett., 262, 127070, 10.1016/j.matlet.2019.127070 Pourfayaz, 2005, CeO2 doped SnO2 sensor selective to ethanol in presence of CO, LPG and CH4, Sensor. Actuator. B Chem., 108, 172, 10.1016/j.snb.2004.12.107 Pourfayaz, 2008, Ceria-doped SnO2 sensor highly selective to ethanol in humid air, Sensor. Actuator. B Chem., 130, 625, 10.1016/j.snb.2007.10.018 Zeng, 2010, Sensitivity improvement of TiO2 - doped SnO2 to volatile organic compounds, Phys. E Low-dimens. Syst. Nanostruct., 43, 633, 10.1016/j.physe.2010.10.010 Zhang, 2021, Enhanced selective acetone gas sensing performance by fabricating ZnSnO3/SnO2 concave microcube, Appl. Surf. Sci., 542, 148555, 10.1016/j.apsusc.2020.148555 Sun, 2020, Low-temperature H2S gas sensor based on spherical Ag3PO4-doped SnO2, New J. Chem., 44, 15966, 10.1039/D0NJ03189E Liu, 2020, Detection of Ppb-level NO2 using mesoporous ZnSe/SnO2 core-shell microspheres based chemical sensors, Sensor. Actuator. B Chem., 320, 128365, 10.1016/j.snb.2020.128365 Xiao, 2015, Enhanced formaldehyde sensing properties of SnO2 nanorods coupled with Zn2SnO4, RSC Adv., 5, 42628, 10.1039/C5RA01887K Mirzaei, 2018, Resistive-based gas sensors for detection of benzene, toluene and xylene (BTX) gases: a review, J. Mater. Chem. C, 6, 4342, 10.1039/C8TC00245B Wang, 2013, Characterization and assessment of volatile organic compounds (VOCs) emissions from typical industries, Chin. Sci. Bull., 58, 724, 10.1007/s11434-012-5345-2 Laurent, 2017, Review of portable and low-cost sensors for the ambient air monitoring of benzene and other volatile organic compounds, Sensors, 17, 1520, 10.3390/s17071520 Lin, 2019, Semiconductor metal oxides as chemoresistive sensors for detecting volatile organic compounds, Sensors, 19, 233, 10.3390/s19020233 Bahuguna, 2020, Innovative approach to photo-chemiresistive sensing technology: surface-fluorinated SnO2 for VOC detection, ACS Appl. Mater. Interfaces, 12, 37320, 10.1021/acsami.0c08847 Chen, 2011, Templating synthesis of SnO2 nanotubes loaded with Ag2O nanoparticles and their enhanced gas sensing properties, Adv. Funct. Mater., 21, 2049, 10.1002/adfm.201002701 Shan, 2013, Excellent toluene sensing properties of SnO2–Fe2O3 interconnected nanotubes, ACS Appl. Mater. Interfaces, 5, 6376, 10.1021/am4015082 Li, 2017, Hierarchical morphology-dependent gas-sensing performances of three-dimensional SnO2 nanostructures, ACS Sens., 2, 102, 10.1021/acssensors.6b00597 Yao, 2020, Construction of novel Pd–SnO2 composite nanoporous structure as a high-response sensor for methane gas, J. Alloys Compd., 826, 154063, 10.1016/j.jallcom.2020.154063 Li, 2017, Formaldehyde detection: SnO2 microspheres for formaldehyde gas sensor with high sensitivity, fast response/recovery and good selectivity, Sensor. Actuator. B Chem., 238, 264, 10.1016/j.snb.2016.07.051 Li, 2016, A high performance methanol gas sensor based on palladium-platinum-In2O3 composited nanocrystalline SnO2, Sensor. Actuator. B Chem., 237, 133, 10.1016/j.snb.2016.06.088 Zhao, 2018, Synthesis and enhanced sensing performance of g-C3N4/SnO2 composites toward isopropanol, Chem. Lett., 47, 881, 10.1246/cl.180296 Hu, 2014, SnO2 nanorods based sensing material as an isopropanol vapor sensor, New J. Chem., 38, 2443, 10.1039/c3nj01482g Hu, 2014, Novel mixed phase SnO2 nanorods assembled with SnO2 nanocrystals for enhancing gas-sensing performance towards isopropanol gas, J. Phys. Chem. C, 118, 9832, 10.1021/jp501550w Zhao, 2018, Raspberry-like SnO2 hollow nanostructure as a high response sensing material of gas sensor toward n-butanol gas, J. Phys. Chem. Solid., 120, 173, 10.1016/j.jpcs.2018.04.032 Kim, 2012, Novel growth of CuO-functionalized, branched SnO2 nanowires and their application to H2S sensors, J. Phys. Appl. Phys., 45, 205301, 10.1088/0022-3727/45/20/205301 Kumar, 2015, Growth and characterization of CuO-doped SnO2 thin films prepared by sequential electron beam evaporation method for application as hydrogen sulfide gas sensor, Res. J. Pharmaceut. Biol. Chem. Sci., 6, 471 Ghosh, 2014, Fast detection of low concentration carbon monoxide using calcium-loaded tin oxide sensors, Sensor. Actuator. B Chem., 203, 490, 10.1016/j.snb.2014.06.111 Yamaura, 2010, CuO/SnO2-In2O3 sensor for monitoring CO concentration in a reducing atmosphere, Sensor. Actuator. B Chem., 153, 465, 10.1016/j.snb.2010.10.044 Trakhtenberg, 2012, Effect of composition on sensing properties of SnO2+In2O3 mixed nanostructured films, Sensor. Actuator. B Chem., 169, 32, 10.1016/j.snb.2012.01.064 Shaposhnik, 2011, Hydrogen sensors on the basis of SnO2-TiO2 systems, Procedia Engineering, 25, 1133, 10.1016/j.proeng.2011.12.279 Li, 2013, In2O3/SnO2 heterojunction microstructures: facile room temperature solid-state synthesis and enhanced Cl2 sensing performance, Sensor. Actuator. B Chem., 185, 110, 10.1016/j.snb.2013.05.010 Vasiliev, 1999, Effect of interdiffusion on electrical and gas sensor properties of CuO/SnO2 heterostructure, Mater. Sci. Eng., B, 57, 241, 10.1016/S0921-5107(98)00432-2 Rumyantseva, 1997, Copper and nickel doping effect on interaction of SnO2 films with H2S, J. Mater. Chem., 7, 1785, 10.1039/a701896g Zhang, 2014, Facile fabrication of a well-ordered porous Cu-doped SnO2 thin film for H2S sensing, ACS Appl. Mater. Interfaces, 6, 14975, 10.1021/am502671s Tischner, 2008, Ultrathin SnO2 gas sensors fabricated by spray pyrolysis for the detection of humidity and carbon monoxide, Sensor. Actuator. B Chem., 134, 796, 10.1016/j.snb.2008.06.032 Wang, 2011, Vanadium-tin oxide nanoparticles with gas-sensing and catalytic activity, J. Am. Ceram. Soc., 94, 4471, 10.1111/j.1551-2916.2011.04733.x Li, 2015, Fabrication of SnO2-SnO nanocomposites with p–n heterojunctions for the low-temperature sensing of NO2 gas, Nanoscale, 7, 12133, 10.1039/C5NR02334C Sun, 2013, Hierarchical α-Fe2O3/SnO2 semiconductor composites: hydrothermal synthesis and gas sensing properties, Sensor. Actuator. B Chem., 182, 336, 10.1016/j.snb.2013.03.019 Das, 2008, Vanadium doped tin dioxide as a novel sulfur dioxide sensor, Talanta, 75, 385, 10.1016/j.talanta.2007.11.010 Singh, 2014, Synthesis and characterization of CuO–SnO2 nanocomposite and its application as liquefied petroleum gas sensor, Mater. Sci. Semicond. Process., 18, 88, 10.1016/j.mssp.2013.11.002 Qi, 2014, Trimethylamine sensors with enhanced anti-humidity ability fabricated from La0.7Sr0.3FeO3 coated In2O3–SnO2 composite nanofibers, Sensor. Actuator. B Chem., 203, 111, 10.1016/j.snb.2014.06.082 Leghrib, 2011, Gas sensors based on doped-CNT/SnO2 composites for NO2 detection at room temperature, Thin Solid Films, 520, 966, 10.1016/j.tsf.2011.04.186 Yu, 2016, Characteristics and preparation of gas sensors using nano SnO2: CNT, Korean Journal of Materials Research, 26, 468, 10.3740/MRSK.2016.26.9.468 Majumdar, 2014, Enhanced performance of CNT/SnO2 thick film gas sensors towards hydrogen, Mater. Chem. Phys., 147, 79, 10.1016/j.matchemphys.2014.04.009 Wu, 2008, Use of CNT/Co3O4-SnO2 in a carbon monoxide sensor operating at room temperatures, Sens. Lett., 6, 848, 10.1166/sl.2008.515 Ippommatsu, 1990, Sensing mechanism of SnO2 gas sensors, J. Mater. Sci., 25, 259, 10.1007/BF00544217