Highly stable hydrogen sensing properties of Pt–ZnO nanoparticle layers deposited on an alumina substrate for high-temperature industrial applications

Platinum (Pt)-decorated zinc oxide (ZnO) nanoparticle (NP) layers were deposited on an alumina (Al2O3) substrate via a magnetron sputtering method, and the resulting Pt–ZnO NP-based sensor was used to detect hydrogen (H2) gas at a high operating temperature of 300 °C, revealing its extremely stable H2 detection properties. Samples of the sensor were characterized using scanning electron, transmission, and atomic force microscopies; X-ray diffractometry; and X-ray photoelectron spectroscopy to determine the optimal structure that exhibits the best sensing performance, prepared by changing the deposition rate and annealing conditions. At a high working temperature of 300 °C, the sensor exhibits resistance changes in the presence of H2 and perfect reversibility in the absence of H2. The fabricated device exhibits a detection range of 100–40,000 ppm and fast response (recovery) time of 133 (112) s toward 1000 ppm (1 vol%) of H2 at 300 °C, with good selectivity. Moreover, the sensor shows highly stable base resistance (~132.5 Ω) and response towards H2 (~14.9%) over long time periods. Thus, the obtained Pt–ZnO/Al2O3 material shows high potential for use in high-temperature working environments where high-performance H2 gas sensors are required. •Pt catalyst metal deposited on ZnO nanoparticle layer for stable hydrogenation and dehydrogenation analysis.•Metal interface with ZnO nanoparticle layer was optimized for enhanced smooth sensing response and recovery time.•Stable response and recovery were achieved at higher temperature range.•Sensor stability achieved in terms of response and base resistance for long term period.