Enhanced room temperature formaldehyde gas sensing properties of hydrothermally synthesized WO3/TiO2 hetero-nanostructures
Source abstract
Abstract
Tungsten trioxide (WO3)-based gas sensors are promising candidates for volatile organic compounds (VOCs) detection, but they suffer from limitations such as baseline drift and poor stability at room temperature. To address these issues, WO3/TiO2nanocomposites were synthesized using the hydrothermal technique. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) confirmed the presence of monoclinic WO3and anatase TiO2with strong interfacial coupling, forming nanoscale heterojunctions. X-ray photoelectron spectroscopy (XPS), photoluminescence, Raman, and FTIR analyses verified heterojunction formation and UV-Vis diffuse reflectance revealed band gap variations between 2.85 and 3.15 eV. The 80%WO3/20%TiO2composite showed excellent formaldehyde gas sensing performance at room temperature, with a high response of 172 to 51 ppm, a detection limit of 5 ppm, and response/recovery times of 36 and 11 s, respectively. Baseline drift was less than 15%. The enhanced sensing properties are attributed to efficient charge separation at the WO3/TiO2interface, demonstrating strong potential for VOC sensing applications.Graphical abstract
Source: expertdata · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Gas Sensing Nanomaterials and Sensors · Transition Metal Oxide Nanomaterials · Advanced Chemical Sensor Technologies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (86)
Show source-provided references
1. X. Yu, T.J. Marks, A. Facchetti, Metal oxides for optoelectronic applications. Nat. Mater. 15(4), 383 (2016)10.1038/nmat4599 ↗
2. H. Ji, W. Zeng, Y. Li, Gas sensing mechanisms of metal oxide semiconductors: a focus review. Nanoscale 11(47), 22664 (2019)10.1039/C9NR07699A ↗
3. S. Uma, M.K. Shobana, Metal oxide semiconductor gas sensors in clinical diagnosis and environmental monitoring. Sens. Actuators A Phys. 349, 114044 (2023)
4. I. Concina, Z.H. Ibupoto, A. Vomiero, Semiconducting metal oxide nanostructures for water splitting and photovoltaics. Adv. Energy Mater. 7(23), 1700706 (2017)10.1002/aenm.201700706 ↗
5. Y. Yao, D. Sang, L. Zou, Q. Wang, C. Liu, A review on the properties and applications of WO3 nanostructure-based optical and electronic devices. Nanomaterials 11(8), 2136 (2021)10.3390/nano11082136 ↗
6. I.M. Szilágyi, B. Fórizs, O. Rosseler, Á. Szegedi, P. Németh, P. Király, G. Tárkányi, B. Vajna, K. Varga-Josepovits, K. László, WO3 photocatalysts: influence of structure and composition. J. Catal. 294, 119 (2012)10.1016/j.jcat.2012.07.013 ↗
7. H.H. Hau, Z. Zahran, D. Chandra, T. Katsuki, Y. Tsubonouchi, N. Hoshino, H. Shiroishi, M. Ishizaki, M. Kurihara, C.M. Hung, Highly stable and efficient photoelectrochemical water oxidation at an anisotropically crystallized monoclinic WO3 film with predominant growth of (202) plane. J. Mater. Chem. A Mater. 2025, 1–12 (2025)
8. X. Wen, J. Luo, K. Xiang, W. Zhou, C. Zhang, H. Chen, High-performance monoclinic WO3 nanospheres with the novel NH4+ diffusion behaviors for aqueous ammonium-ion batteries. Chem. Eng. J. 458, 141381 (2023)
9. X. Chang, X. Dong, X. Liu, Y. Tong, K. Li, Z. Li, Y. Lu, Constructing a hexagonal/orthorhombic WO3 phase junction for enhanced photochromism. Opt. Mater. 142, 114131 (2023)10.1016/j.optmat.2023.114131 ↗
10. S. Wang, H. Xu, T. Hao, P. Wang, X. Zhang, H. Zhang, J. Xue, J. Zhao, Y. Li, In situ XRD and operando spectra-electrochemical investigation of tetragonal WO3−x nanowire networks for electrochromic supercapacitors. NPG Asia Mater. 13(1), 51 (2021)10.1038/s41427-021-00319-7 ↗
11. P. Guo, B. Tian, J. Liang, X. Yang, G. Tang, Q. Li, Q. Liu, K. Zheng, X. Chen, W. Wu, An all-printed, fast-response flexible humidity sensor based on Hexagonal-WO3 nanowires for multifunctional applications. Adv. Mater. 35(41), 2304420 (2023)10.1002/adma.202304420 ↗
12. C. Nomellini, A. Polo, C.A. Mesa, E. Pastor, G. Marra, I. Grigioni, M.V. Dozzi, S. Giménez, E. Selli, Improved photoelectrochemical performance of WO3/BiVO4 heterojunction photoanodes via WO3 nanostructuring. ACS Appl. Mater. Interfaces 15(45), 52436 (2023)
13. K. Kato, Y. Uemura, K. Asakura, A. Yamakata, Role of oxygen vacancy in the photocarrier dynamics of WO3 photocatalysts: the case of recombination centers. J. Phys. Chem. C 126(22), 9257 (2022)10.1021/acs.jpcc.2c01662 ↗
14. D. Bonardo, N.L.W. Septiani, F. Amri, S. Humaidi, B. Yuliarto, Recent development of WO3 for toxic gas sensors applications. J. Electrochem. Soc. 168(10), 107502 (2021)10.1149/1945-7111/ac0172 ↗
15. M. Modak, S. Rane, S. Jagtap, WO3: a review of synthesis techniques, nanocomposite materials and their morphological effects for gas sensing application. Bull. Mater. Sci. 46(1), 28 (2023)10.1007/s12034-022-02864-5 ↗
16. Shreya, P. Phogat, R. Jha, S. Singh, Microwave-synthesized γ-WO3 nanorods exhibiting high current density and diffusion characteristics. Transit. Metal Chem. 48(3), 167 (2023)10.1007/s11243-023-00533-y ↗
17. S. Ma, F. Chen, Y. Liu, H. Zhang, P. Jia, D. Zhang, Pd-doped WO3 nanoplates for hydrogen sensing: experimental studies and density functional theory investigations. ACS Appl. Nano Mater. 7(13), 15298 (2024)10.1021/acsanm.4c02114 ↗
18. M. Abbaspoor, M. Aliannezhadi, F.S. Tehrani, High-performance photocatalytic WO3 nanoparticles for treatment of acidic wastewater. J. Solgel Sci. Technol. 105(2), 565 (2023)10.1007/s10971-022-06002-9 ↗
19. A. Staerz, C. Berthold, T. Russ, S. Wicker, U. Weimar, N. Barsan, The oxidizing effect of humidity on WO3 based sensors. Sens. Actuators B Chem. 237, 54 (2016)10.1016/j.snb.2016.06.072 ↗
20. X. Li, L. Fu, H. Karimi-Maleh, F. Chen, S. Zhao, Innovations in WO3 gas sensors: nanostructure engineering, functionalization, and future perspectives. Heliyon 10, e27760 (2024)10.1016/j.heliyon.2024.e27760 ↗
21. A. Khan, M.A. Gaikwad, J.H. Kim, A. Kadam, An overview and experimental analysis of WO3/TiO2 composite with enhanced electrochromic properties for smart windows application. Tungsten 6(4), 732 (2024)10.1007/s42864-024-00269-x ↗
22. Z. Li, W. Zeng, Q. Li, SnO2 as a gas sensor in detection of volatile organic compounds: a review. Sens. Actuators A Phys. 346, 113845 (2022)
23. M. Waqas Alam, A. Sharma, A. Sharma, S. Kumar, P. Mohammad Junaid, M. Awad, VOC detection with zinc oxide gas sensors: a review of fabrication, performance, and emerging applications. Electroanalysis 37(1), e202400246 (2025)10.1002/elan.202400246 ↗
24. S. Ramanavicius, A. Ramanavicius, Insights in the application of stoichiometric and non-stoichiometric titanium oxides for the design of sensors for the determination of gases and VOCs (TiO2−x and TinO2n−1 vs TiO2). Sensors 20(23), 6833 (2020)10.3390/s20236833 ↗
25. H. Liu, L. Duan, K. Xia, Y. Chen, Y. Li, S. Deng, J. Xu, Z. Hou, Microwave synthesized 2D WO3 nanosheets for VOCs gas sensors. Nanomaterials 12(18), 3211 (2022)10.3390/nano12183211 ↗
26. A. Kumar, Structural and gas sensing properties of nanocrystalline WO3: TiO2-based hydrogen gas sensors. Int. J. Adv. Educ. Res. 3, 383 (2018)
27. V. Galstyan, N. Poli, V. Golovanov, A. D’Arco, S. Macis, S. Lupi, E. Bolli, S. Kaciulis, A. Mezzi, E. Comini, Tunable chemical reactivity and selectivity of WO3/TiO2 heterojunction for gas sensing applications. Adv. Mater. Technol. 7(12), 2201751 (2022)10.1002/admt.202201751 ↗
28. H. Li, C.-H. Wu, Y.-C. Liu, S.-H. Yuan, Z.-X. Chiang, S. Zhang, R.-J. Wu, Mesoporous WO3-TiO2 heterojunction for a hydrogen gas sensor. Sens. Actuators B Chem. 341, 130035 (2021)
29. M. Kumaresan, M. Venkatachalam, M. Saroja, P. Gowthaman, TiO2 nanofibers decorated with monodispersed WO3 heterostruture sensors for high gas sensing performance towards H2 gas. Inorg. Chem. Commun. 129, 108663 (2021)10.1016/j.inoche.2021.108663 ↗
30. G. Mathankumar, P. Bharathi, M.K. Mohan, S. Harish, M. Navaneethan, J. Archana, P. Suresh, G.K. Mani, P. Dhivya, S. Ponnusamy, Synthesis and functional properties of nanostructured Gd-doped WO3/TiO2 composites for sensing applications. Mater. Sci. Semicond. Process. 105, 104732 (2020)10.1016/j.mssp.2019.104732 ↗
31. Z. Wu, Z. Chen, Z. Deng, N. Dai, Y. Sun, M. Ge, A high-performance room-temperature NH3 gas sensor based on WO3/TiO2 nanocrystals decorated with Pt NPs. RSC Adv. 14(17), 12225 (2024)10.1039/D4RA00881B ↗
32. W. Li, B. Zhang, X. Dong, Q. Lu, H. Shen, Y. Ni, Y. Liu, H. Song, Electrospun WO3/TiO2 core-shell nanowires for triethylamine gas sensing. Chemosensors 13(2), 45 (2025)10.3390/chemosensors13020045 ↗
33. K. Ahmad, D.T. Nde, R.A. Khan, Hydrothermal synthesis of bismuth-doped tungsten trioxide (Bi-WO3) for photocatalytic hydrogen production application. React. Kinet. Mech. Catal. 137(6), 3487 (2024)10.1007/s11144-024-02679-x ↗
34. Y. Masuda, K. Kato, Synthesis and phase transformation of TiO2 nano-crystals in aqueous solutions. J. Ceram. Soc. Jpn. 117(1363), 373 (2009)10.2109/jcersj2.117.373 ↗
35. S. Chalotra, K. Seth, P. Kaur, S. Kaur, D.P. Singh, Structural and optical studies of TiO2 doped tungsten oxide. AIP Conf. Proc. 2220(1), 20078 (2020)10.1063/5.0002713 ↗
36. R. Wahyuono, L. Ernawati, I.K. Maharsih, N. Widiastuti, H. Widiyandari, Mesoporous WO3/TiO2 nanocomposites photocatalyst for rapid degradation of methylene blue in aqueous medium. Int. J. Eng. 32(10), 1345 (2019)
37. D.T.T. Le, N.D.H. Long, C.T. Xuan, N. Van Toan, C.M. Hung, N. Van Duy, L.T. Theu, V.A. Dinh, N.D. Hoa, Porous CoFe2O4 nanorods: VOC gas-sensing characteristics and DFT calculation. Sens. Actuators B Chem. 379, 133286 (2023)10.1016/j.snb.2023.133286 ↗
38. N. Ta, J. Liu, S. Chenna, P.A. Crozier, Y. Li, A. Chen, W. Shen, Stabilized gold nanoparticles on ceria nanorods by strong interfacial anchoring. J. Am. Chem. Soc. 134(51), 20585 (2012)10.1021/ja310341j ↗
39. B.B. Wang, X.X. Zhong, J. Zhu, Y. Wang, Y. Zhang, U. Cvelbar, K. Ostrikov, Tuned structures and enhanced photoluminescence of WO3−x nanomaterials by TiO2. Mater. Sci. Eng. B 275, 115516 (2022)
40. Y. Zhang, C. Cheng, F. Xing, Z. Li, C. Huang, Transient metal centers at the covalent heterointerface favor photocatalytic hydrogen evolution. ACS Appl. Mater. Interfaces 15(26), 31364 (2023)10.1021/acsami.3c02662 ↗
41. I. Kavre Piltaver, R. Peter, K. Salamon, M. Micetic, M. Petravic, In situ X-ray photoelectron spectroscopy study of initial stages of tungsten trioxide reduction by low-energy hydrogen bombardment. J. Phys. Chem. C 128(12), 5345 (2024)10.1021/acs.jpcc.4c00448 ↗
42. M. Hunsom, N. Kunthakudee, P. Ramakul, K. Serivalsatit, S. Sangkhanak, P. Wongyongnoi, K. Pruksathorn, Rapid photocatalytic gold recovery from industrial cyanide-based gold plating wastewater via TiO2/WO3 nanocomposites: role of mixed hole scavengers and operating conditions. J. Environ. Chem. Eng. 11(5), 110534 (2023)10.1016/j.jece.2023.110534 ↗
43. W. Gan, X. Fu, J. Jin, J. Guo, M. Zhang, R. Chen, C. Ding, Y. Lu, J. Li, Z. Sun, Nitrogen-rich carbon nitride (C3N5) coupled with oxygen vacancy TiO2 arrays for efficient photocatalytic H2O2 production. J. Colloid Interface Sci. 653, 1028 (2024)10.1016/j.jcis.2023.09.136 ↗
44. H. Shi, S. Zhang, X. Zhu, Y. Liu, T. Wang, T. Jiang, G. Zhang, H. Duan, Uniform gold-nanoparticle-decorated {001}-faceted anatase TiO2 nanosheets for enhanced solar-light photocatalytic reactions. ACS Appl. Mater. Interfaces 9(42), 36907 (2017)10.1021/acsami.7b12470 ↗
45. Q. Wang, W. Zhang, X. Hu, L. Xu, G. Chen, X. Li, Hollow spherical WO3/TiO2 heterojunction for enhancing photocatalytic performance in visible-light. J. Water Process Eng. 40, 101943 (2021)
46. S. Sun, J. Zhang, P. Gao, Y. Wang, X. Li, T. Wu, Y. Wang, Y. Chen, P. Yang, Full visible-light absorption of TiO2 nanotubes induced by anionic S22− doping and their greatly enhanced photocatalytic hydrogen production abilities. Appl. Catal. B 206, 168 (2017)10.1016/j.apcatb.2017.01.027 ↗
47. M. Farhadian, P. Sangpour, G. Hosseinzadeh, Morphology dependent photocatalytic activity of WO3 nanostructures. J. Energy Chem. 24(2), 171 (2015)10.1016/S2095-4956(15)60297-2 ↗
48. M. Abaker, A. Umar, S. Baskoutas, S.H. Kim, S.W. Hwang, Structural and optical properties of CuO layered hexagonal discs synthesized by a low-temperature hydrothermal process. J. Phys. D Appl. Phys. 44(15), 155405 (2011)10.1088/0022-3727/44/15/155405 ↗
49. H.D. Cho, I.T. Yoon, K.B. Chung, D.Y. Kim, T.W. Kang, S.U. Yuldashev, Low-temperature photoluminescence of WO3 nanoparticles. J. Lumin. 195, 344 (2018)10.1016/j.jlumin.2017.11.053 ↗
50. A. Yordanova, L. Aleksandrov, M. Milanova, R. Iordanova, P. Petrova, N. Nedyalkov, Molecules 29, 1 (2024)
51. J. Liu, J. Li, A. Sedhain, J. Lin, H. Jiang, Structure and photoluminescence study of TiO2 nanoneedle texture along vertically aligned carbon nanofiber arrays. J. Phys. Chem. C 112(44), 17127 (2008)10.1021/jp8060653 ↗
52. J.C. Yu, J. Yu, W. Ho, A. Jiang, A. Zhang, Effects of F- doping on the photocatalytic activity and microstructures of nanocrystalline TiO2 powders. Chem. Mater. 14(9), 3808 (2002)10.1021/cm020027c ↗
53. F.B. Li, X.Z. Li, The enhancement of photodegradation efficiency using Pt–TiO2 catalyst. Chemosphere 48(10), 1103 (2002)10.1016/S0045-6535(02)00201-1 ↗
54. Y. Lei, L.D. Zhang, G.W. Meng, G.H. Li, X.Y. Zhang, C.H. Liang, W. Chen, S.X. Wang, Preparation and photoluminescence of highly ordered TiO2 nanowire arrays. Appl. Phys. Lett. 78(8), 1125 (2001)10.1063/1.1350959 ↗
55. C. Wei, X. Chen, D. Li, H. Su, H. He, J.-F. Dai, Bound exciton and free exciton states in GaSe thin slab. Sci. Rep. 6(1), 33890 (2016)10.1038/srep33890 ↗
56. X. Lao, Z. Yang, Z. Su, Z. Wang, H. Ye, M. Wang, X. Yao, S. Xu, Luminescence and thermal behaviors of free and trapped excitons in cesium lead halide perovskite nanosheets. Nanoscale 10(21), 9949 (2018)10.1039/C8NR01109E ↗
57. M. Mersal, G.G. Mohamed, A.F. Zedan, Promoted visible-light-assisted oxidation of methanol over N-doped TiO2/WO3 nanostructures. Opt. Mater. 122, 111810 (2021)10.1016/j.optmat.2021.111810 ↗
58. Y. Yang, G. Ma, X. Hu, W. Wang, Z. Du, Y. Wang, X. Gong, H. Tan, F. Guo, J. Tang, Hollow flower-like WO3@ TiO2 heterojunction microspheres for the photocatalytic degradation of rhodamine B and tetracycline. RSC Adv. 15(16), 12629 (2025)10.1039/D5RA01412C ↗
59. T. Yang, H. Jiang, O. Hai, Y. Dong, S. Liu, S. Gao, Effect of oxygen vacancies on the persistent luminescence of Y3Al2Ga3O12:Ce3+, Yb3+ phosphors. Inorg. Chem. 60(23), 17797 (2021)10.1021/acs.inorgchem.1c02420 ↗
60. S. Mochizuki, T. Shimizu, F. Fujishiro, Photoluminescence study on defects in pristine anatase and anatase-based composites. Phys. B Condens. Matter. 340–342, 956 (2003)10.1016/j.physb.2003.09.172 ↗
61. H. Zheng, C. Wang, X. Zhang, L. Kong, Y. Li, Y. Liu, Y. Liu, Ultrasonic spray pyrolysis assembly of a TiO2–WO3–Pt multi-heterojunction microsphere photocatalyst using highly crystalline WO3 nanosheets: less is better. New J. Chem. 40(4), 3225 (2016)10.1039/C5NJ02981C ↗
62. V.V. Ganbavle, G.L. Agawane, A.V. Moholkar, J.H. Kim, K.Y. Rajpure, Structural, optical, electrical, and dielectric properties of the spray-deposited WO3 thin films. J. Mater. Eng. Perform. 23(4), 1204 (2014)10.1007/s11665-014-0873-3 ↗
63. M. Giarola, A. Sanson, F. Monti, G. Mariotto, M. Bettinelli, A. Speghini, G. Salviulo, Vibrational dynamics of anatase TiO2: polarized Raman spectroscopy and ab initio calculations. Phys. Rev. B Condens. Matter Mater. Phys. 81(17), 174305 (2010)10.1103/PhysRevB.81.174305 ↗
64. B. Orel, N. Grošelj, U.O. Krašovec, R. Ješe, A. Georg, IR spectroscopic investigations of gasochromic and electrochromic sol-gel - Derived peroxotungstic acid/ormosil composite and crystalline WO3 films. J. Solgel Sci. Technol. 24(1), 5 (2002)10.1023/A:1015147530846 ↗
65. O. Sadek, S. Touhtouh, M. Rkhis, A. Hajjaji, Study of the hydroxylation of the TiO2 thin layer prepared by spin-coating method using FTIR analysis and DFT theory. Inorg. Chem. Commun. 161, 112092 (2024)10.1016/j.inoche.2024.112092 ↗
66. C. Balázsi, J. Pfeifer, Long-term behaviour of tungsten oxide hydrate gels in an alkali containing aqueous environment. Sol. Energy Mater. Sol. Cells 76(4), 577 (2003)10.1016/S0927-0248(02)00268-4 ↗
67. A. Chemseddine, F. Babonneau, J. Livage, Anisotropic WO3·nH2O layers deposited from gels. J. Non Cryst. Solids 91(2), 271 (1987)10.1016/S0022-3093(87)80311-3 ↗
68. M. Deepa, M. Kar, S.A. Agnihotry, Electrodeposited tungsten oxide films: annealing effects on structure and electrochromic performance. Thin Solid Films 468(1), 32 (2004)10.1016/j.tsf.2004.04.056 ↗
69. A. Gutiérrez-Alejandre, J. Ramírez, G. Busca, A vibrational and spectroscopic study of WO3/TiO2−Al2O3 catalyst precursors. Langmuir 14(3), 630 (1998)10.1021/la970993n ↗
70. K.-I. Choi, S.-J. Hwang, Z. Dai, Y. Chan Kang, J.-H. Lee, Rh-catalyzed WO3 with anomalous humidity dependence of gas sensing characteristics. RSC Adv. 4(95), 53130 (2014)10.1039/C4RA06654E ↗
71. X. Li, L. Fu, H. Karimi-Maleh, F. Chen, S. Zhao, Innovations in WO3 gas sensors: nanostructure engineering, functionalization, and future perspectives. Heliyon 10(6), e27740 (2024)
72. N. Barsan, U. Weimar, Conduction model of metal oxide gas sensors. J. Electroceram. 7, 143 (2001)10.1023/A:1014405811371 ↗
73. Z. Yuan, C. Yang, F. Meng, Chemosensors 9, 1 (2021)10.3390/chemosensors9070179 ↗
74. C. Lou, G. Lei, X. Liu, J. Xie, Z. Li, W. Zheng, N. Goel, M. Kumar, J. Zhang, Design and optimization strategies of metal oxide semiconductor nanostructures for advanced formaldehyde sensors. Coord. Chem. Rev. 452, 214280 (2022)
75. C. Liu, J. Hu, G. Wu, J. Cao, Z. Zhang, Y. Zhang, Carbon nanotube-based field-effect transistor-type sensor with a sensing gate for Ppb-level formaldehyde detection. ACS Appl. Mater. Interfaces 13(47), 56309 (2021)10.1021/acsami.1c17044 ↗
76. Z. Lou, F. Li, J. Deng, L. Wang, T. Zhang, Branch-like hierarchical heterostructure (α-Fe2O3/TiO2): a novel sensing material for trimethylamine gas sensor. ACS Appl. Mater. Interfaces 5(23), 12310 (2013)10.1021/am402532v ↗
77. N. Zhang, X. Li, Y. Guo, Y. Guo, Q. Dai, L. Wang, W. Zhan, Crystal engineering of TiO2 for enhanced catalytic oxidation of 1, 2-dichloroethane on a Pt/TiO2 catalyst. Environ. Sci. Technol. 57(17), 7086 (2023)10.1021/acs.est.3c00165 ↗
78. Y. Lu, H. Deng, T. Pan, L. Wang, C. Zhang, H. He, Interaction between noble metals (Pt, Pd, Rh, Ir, Ag) and defect-enriched TiO2 and its application in toluene and propene catalytic oxidation. Appl. Surf. Sci. 606, 154834 (2022)
79. Y. Li, N. Chen, D. Deng, X. Xing, X. Xiao, Y. Wang, Formaldehyde detection: SnO2 microspheres for formaldehyde gas sensor with high sensitivity, fast response/recovery and good selectivity. Sens. Actuators B Chem. 238, 264 (2017)10.1016/j.snb.2016.07.051 ↗
80. X. Ma, J. Shen, D. Hu, L. Sun, Y. Chen, M. Liu, C. Li, S. Ruan, Preparation of three-dimensional Ce-doped Sn3O4 hierarchical microsphere and its application on formaldehyde gas sensor. J. Alloys Compd. 726, 1092 (2017)10.1016/j.jallcom.2017.08.079 ↗
81. J. Huang, H. Liang, J. Ye, D. Jiang, Y. Sun, X. Li, Y. Geng, J. Wang, Z. Qian, Y. Du, Ultrasensitive formaldehyde gas sensor based on Au-loaded ZnO nanorod arrays at low temperature. Sens. Actuators B Chem. 346, 130568 (2021)
82. D. Meng, D. Liu, G. Wang, Y. Shen, X. San, M. Li, F. Meng, Low-temperature formaldehyde gas sensors based on NiO-SnO2 heterojunction microflowers assembled by thin porous nanosheets. Sens. Actuators B Chem. 273, 418 (2018)10.1016/j.snb.2018.06.030 ↗
83. Z. Cai, J. Park, S. Park, Porous In2O3–ZnO nanofiber-based sensor for ultrasensitive room-temperature detection of toluene gas under UV illumination. J. Market. Res. 24, 2482 (2023)
84. M.D. Fernández-Ramos, L.F. Capitán-Vallvey, L.M. Pastrana-Martínez, S. Morales-Torres, F.J. Maldonado-Hódar, Chemoresistive NH3 gas sensor at room temperature based on the carbon gel-TiO2 nanocomposites. Sens. Actuators B Chem. 368, 132103 (2022)10.1016/j.snb.2022.132103 ↗
85. A. Chattopadhyay, J. Nayak, Enhanced room temperature sensitivity of undoped HfO2 nanoparticles towards formaldehyde gas. Appl. Phys. A 127(12), 904 (2021)10.1007/s00339-021-05072-w ↗
86. A. Chattopadhyay, J. Nayak, Hafnium oxide nanoparticles synthesized via sol-gel route for an efficient detection of volatile organic compounds at room temperature. Mater. Sci. Semicond. Process. 139, 106336 (2022)10.1016/j.mssp.2021.106336 ↗