High-performance nitrogen dioxide gas sensor for ppb-level detection based on GaN nanoshuttles

Abstract

GaN nanoshuttles have been successfully fabricated via facile hydrothermal and further nitridation method. The morphology and structure indicate that GaN nanoshuttles have large specific surface area and plentiful oxygen adsorption sites. The sensor based on GaN nanoshuttles has the most superior response of 14.56 towards 100 ppm NO2 at optimum temperature of 250 °C, meanwhile exhibiting rapid response and recovery time of 31 s and 36 s. The GaN nanoshuttles gas sensor also possesses a low detection limit (5 ppb), outstanding anti-interference performance, excellent selectivity and stable repeatability. Finally, the gas sensing mechanism is interpreted in detail. The GaN nanoshuttles gas sensor was verified to have the potential for ppb-level NO2 gas detection.