HYDROTHERMAL SYNTHESIS OF POROUS ZnO NANO/MICRORODS FOR HIGHLY SENSITIVE NO2 GAS SENSING | Minh | TNU Journal of Science and Technology

HYDROTHERMAL SYNTHESIS OF POROUS ZnO NANO/MICRORODS FOR HIGHLY SENSITIVE NO2 GAS SENSING

About this article

Received: 08/07/25                Revised: 21/11/25                Published: 25/11/25

Authors

1. Luu Hoang Minh, Hanoi University of Civil Engineering
2. Pham Thi Thuy Thu, Hanoi University of Civil Engineering
3. Pham Van Tong Email to author, Hanoi University of Civil Engineering

Abstract


This study presents a simple, low-cost hydrothermal synthesis method for fabricating porous ZnO nano/microrods without the use of surfactants, combined with a thermal treatment process. The resulting material exhibits a highly porous structure, which significantly increases the specific surface area and enhances effective interactions with gas molecules. When applied in gas sensors, the material demonstrates excellent NO2 detection capabilities at low concentrations (0.1–2.0 ppm), with a high response and an optimal operating temperature of only 150 °C. The sensor also shows fast response time, stable repeatability, good recovery, and high selectivity toward NO2 compared to reducing gases and volatile organic compounds such as H2, CO, NH3, ethanol, and acetone. These results affirm the potential of porous ZnO nanorods for developing high-performance NO2 gas sensors, paving the way for practical applications in air quality monitoring.

Keywords


Gas sensor; ZnO; Hydrothermal; NO2; Nano/Microstructures

References


[1] N. Elsayed, "Toxicity of nitrogen dioxide: an introduction," Toxicology, vol. 89, pp. 161–174, 1994.

[2] Y.O. Khaniabadi, G. Goudarzi, S. M. Daryanoosh, A. Borgini, A. Tittarelli, and A. De Marco, "Exposure to PM10, NO2, and O3 and impacts on human health," Environ. Sci. Pollut. Res., vol. 24, pp. 2781-2789, 2017.

[3] Z. Fan and J. G. Lu, "Chemical Sensing with ZnO Nanowire," IEEE Sensors, vol. 158, pp. 834–836, 2005.

[4] S. Kundu, M. Sarkar, J. Shaji, and R. Ghosh, "Resistive sensor for tetradecane and H2S based on SnO2 nanoparticles," Sensors Actuators A Phys., vol. 391, pp. 116635-116643, 2025.

[5] Ü. Özgür, Y. I. Alivov, C. Liu, A. Teke, M. A. Reshchikov, S. Doğan, V. Avrutin, S.-J. Cho, and H. Morkoç, "A comprehensive review of ZnO materials and devices," J. Appl. Phys., vol. 98, pp. 041301-041403, 2005.

[6] Y. H. Navale, S. T. Navale, N. S. Ramgir, F. J. Stadler, S. K. Gupta, D. K. Aswal, and V. B. Patil, "Zinc oxide hierarchical nanostructures as potential NO2 sensors," Sensors Actuators B Chem., vol. 251, pp. 551–563, 2025.

[7] X. Chen, Y. Shen, W. Zhang, J. Zhang, D. Wei, R. Lu, L. Zhu, H. Li, and Y. Shen, "In-situ growth of ZnO nanowire arrays on the sensing electrode via a facile hydrothermal route for high-performance NO2 sensor," Appl. Surf Sci., vol. 435, pp. 1096–1104, 2018.

[8] T. V. A. Kusumam, V. S. Siril, K. N. Madhusoodanan, M. Prashantkumar, Y. T. Ravikiran, and N. K. Renuka, "NO2 gas sensing performance of zinc oxide nanostructures synthesized by surfactant assisted Low temperature hydrothermal technique," Sensors Actuators A Phys., vol. 318, pp. 112389-112397, 2021.

[9] J. Zhang, S. Wang, Y. Wang, M. Xu, H. Xia, S. Zhang, W. Huang, X. Guo, and S. Wu, "ZnO hollow spheres: Preparation, characterization, and gas sensing properties," Sensors Actuators B Chem., vol. 139, pp. 411–417, 2009.

[10] V. T. Pham, T. T. T. Pham, and M. T. Luong, "Synthesis of WO3 nanorods by hydrothermal method for CO gas sensor applications," Sci. J. Tan Trao Univ., vol. 7, pp. 22–29, 2021.

[11]H. M. Luu, T. T. T. Pham, Q. T. Bui, T. H. Nguyen, T. T. H. Do, V. T. Nguyen, M. H. Chu, V. D. Nguyen, V. T. Pham, and D. H. Nguyen, "Hollow ZnO nanorices prepared by a simple hydrothermal method for NO2 and SO2 gas sensors," RSC Adv, vol. 11, pp. 33613–33625, 2021.

[12] J. Huang, C. Shi, G. Fu, P. Sun, X. Wang, and C. Gu, "Facile synthesis of porous ZnO microbelts and analysis of their gas-sensing property," Materials Chemistry and Physics, vol. 144, pp. 343–348, 2014, doi: 10.1016/j.matchemphys.2013.12.050.

[13] H. M. Luu, T. T. T. Pham, V. D. Nguyen, and V. T. Pham, "Excellent NO2 sensor based on porous Pd-ZnO nanorods prepared by a facile hydrothermal method," Adv. Nat. Sci. Nanosci Nanotechnol, vol. 15, pp. 035005-035016, 2024.

[14] T. Q. Chu, X. T. Nguyen, D. H. Nguyen, T. T. L. Dang, M. H. Chu, V. D. Nguyen, and V. H. Nguyen, "C2H5OH and NO2 sensing properties of ZnO nanostructures: correlation between crystal size, defect level and sensing performance," RSC Adv, vol. 8, pp. 5629–5639, 2018.

[15] S. Peng, G. Wu, W. Song, and Q. Wang, "Application of flower-like ZnO nanorods gas sensor detecting decomposition products," J. Nanomater, vol. 2013, pp. 1–7, 2013.




DOI: https://doi.org/10.34238/tnu-jst.13189

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