One-Step Solvothermal Construction of ZnWO4/ZnO Heterostructures for Enhanced NO2 Sensing at Room Temperature

Excessive NO 2 emissions not only damage the ecological environment but also endanger human health. Therefore, developing gas sensors for efficient detection of NO 2 gas is essential. In this study, a one-step solvothermal method was used to prepare the ZnWO 4 /ZnO heterostructure for NO 2 detection at room temperature (RT). The ZnWO 4 /ZnO sensors showed an excellent response for NO 2 (174.5/3 ppm) and a low detection limit of 10 ppb at RT. The synergistic interaction between the heterostructure and oxygen vacancies contributes to the superior sensing capability of ZnWO 4 /ZnO heterostructures. The construction of the heterostructure accelerates charge separation and migration, while oxygen vacancies provide abundant active sites and adsorption sites for gas molecules. This work offers a viable strategy for developing highly sensitive ZnWO 4 /ZnO-based gas sensors at RT.