Enhanced low-working temperature 2-butanone gas-sensing performance of N-doped ZnO mesoporous nanosheets

In this work, N-doped ZnO (ZnON) mesoporous nanosheets were prepared via a two-step growth strategy, which consisted of a low temperature hydrothermal method and nitriding annealing process, and used to construct low-working temperature gas sensor for 2-Butanone selective detection successfully. The mesoporous nanosheets were characterized by XRD, SEM, BET, and XPS, and the effects of nitriding temperature on structure and gas sensitivity were discussed. ZnON series materials still retained channel structure, while adding an additional absorption band in the range of 500–650 nm, which was generated by N-doping. The optimal nitriding temperature was 450 °C and the related ZnON-450 gas sensor had the best response to 2-butanone vapor at a low-working temperature of 130 °C, and the sensitivity to 100 ppm 2-butanone was 23.3, which was 19 times higher than that of pure ZnO-450. The enhanced gas-sensing performance of ZnON-450 was discussed, which could be attributed to the synergy effect of shallow energy levels introduced by N-doping, nucleophilic hanging groups of -NH₂ and specific mesoporous nanosheet structure. This work provides a promising route for the well development of low-working temperature N-doped electronic devices.