Pt–SnO2 composite nanoceramics: Maintaining extraordinary room–temperature hydrogen sensing capability over 365 days in a practical way

It is important for metal oxides to continuously uphold applicable room–temperature gas sensing capability for hundreds of days for practical applications. In this study, an exploration has been conducted to maintain an extraordinary room–temperature hydrogen sensing capability for 1 wt% Pt–SnO 2 composite nanoceramics over a prolonged time in a practical way. Though as–prepared samples’ room–temperature responses to hydrogen weakened obviously with time, they were completely restored through mild heat treatments like 200 °C for 15 min using commercial Al 2 O 3 ceramic heating plates of 10 mm × 10 mm. With such ceramic heating plates to provide a periodic heat treatment of 200 °C for 15 min in every three days, a room-temperature response over 1000 to 1 % H 2 –20 % O 2 –N 2 has been continuously maintained for samples over 365 days. It is suggested that some heaters should be incorporated into future room–temperature metal oxide gas sensors, whose periodic heat treatment will be crucial to maintain room–temperature gas sensing capability at minimum energy consumption for the sensors over their lifespan of service.