High sensitivity and selectivity of h-BN/WO n-n heterojunction to triethylamine at low-temperature.

Due to the unique properties of heterojunction interfaces, heterojunction materials have broad application prospects in gas sensors. In this work, a facile and economical two-step synthesis method was employed to fabricate h-BN/WO heterojunctions, exhibiting excellent performance in triethylamine (TEA) detection. The results indicate that compared to pure WO sensors, h-BN/WO sensors exhibit superior TEA sensing capabilities, with an excellent response of 281.45 to 20 ppm TEA at 100 °C, which is 3.4 times higher. Moreover, h-BN/WO sensors demonstrate favorable response times, low detection limits, and good stability. These significant enhancements are attributed to the increase in oxygen vacancies and the establishment of heterojunctions between h-BN and WO. Heterojunctions can regulate the concentration and transport rate of charge carriers, as well as the interface potential barrier, thereby affecting the gas sensing processes. This work may promote the further development of sensing materials and the practical application of WO sensors in TEA detection.