Hydrothermal Synthesis of SnO₂ Doped NiO Nanoparticles for Acute Detection of Ethanol Gas

Abstract:

The detection of ethanol (C₂H₆O), a toxic and hazardous gas, is important for environmental monitoring and industrial safety. This study synthesised a SnO₂-doped NiO (SnO₂-NiO) heterojunction via a hydrothermal method for high-performance ethanol gas sensing applications. The thick films of synthesized materials were developed by using the screen printing technique. In this work, SnO₂ is used as a dopant while NiO is base material. The concentration of SnO₂ is varied from 0.1 N, 0.3 N, 0.5 N, to 0.7 N in the NiO during synthesis. The nanostructure leverages the superior gas-sensing properties of the n-type semiconducting behavior of SnO₂ and the p-type semiconducting behavior of NiO, forming an efficient p-n heterojunction interface. The synthesized material was characterized using X-ray diffraction (XRD), TEM (Transmission Electron Microscopy), field emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy (EDS) to confirm the formation of the heterojunction and analyze its morphology and elemental composition. Gas sensing examinations demonstrated that the SnO₂-doped NiO heterojunction exhibited excellent selectivity (86.74%) and sensitivity towards ethanol at 150°C operating temperatures, with rapid response and recovery times. The enhanced gas-sensing performance is attributed to the synergistic effects between SnO₂ and NiO, which promote electron transfer and improve the interaction with ethanol gas molecules. This work highlights the potential of SnO₂-doped NiO heterojunction in developing highly sensitive and selective ethanol gas sensors for environmental and industrial applications.

• Periodical: Advanced Materials Research (Volume 1184)
• Pages: 13-34
• DOI: https://doi.org/10.4028/p-c3JQ7t
• Online since: November 2025
• Authors: Aparna Amit Kulkarni*, Gotan Hiralal Jain, Rajendra Popatrao Patil, Madhavrao Keshavrao Deore, Ganesh E. Patil, Sarika Digambar Shinde
• Keywords: Ethanol Gas, Gas Sensors, Heterojunction, Industrial Applications, Selectivity

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