Oat-seed-like W18O49 mesocrystals for highly sensitive low-temperature NO2 sensing application

Oat-seed-like W18O49 (OSL_W18O49) mesocrystals were synthesized through hydrothermal method based on a facile one-step procedure. The microstructure characterization based on SEM and TEM (scanning electron microscope and transmission electron microscope) shows the self-assembled nanowires for the formation of as-prepared oat-seed-like W18O49 nanomaterials. Gas sensing measurements indicate that the oat-seed-like W18O49 based sensor exhibits good response (2.6 and 9.6 toward 1 ppm NO2 at 25 degrees C and 90 degrees C, respectively) with excellent gas selectivity, rapid response speed and fast recovery time. Owing to the enhanced excellent performance, our results demonstrate the application potential of oat-seed-like W18O49 for NO2 detecting at low temperature. This work opens an easy pathway for facile preparation of mesocrystal W18O49 and it is a novel strategy to design gas-sensing materials for sensing volatile organic compounds with high performance.