Rapid detection and good anti-humidity performance of resistive n-propanol gas sensor based on an ordered open porous ZnSnO3/ZnO heterostructures

The research on the synthesis of three-dimensional (3D) porous structures has garnered significant interest among scholars. In this study, ZnSnO 3 /ZnO heterostructures are prepared using butterfly wings as biotemplates, resulting in the formation of a hierarchical porous network structure characterized by regular ridges and pillars. Subsequently, we construct a resistive gas sensor utilizing these ZnSnO 3 /ZnO heterostructures, which exhibits not only a relatively high responses (14.7) but also rapid response and recovery speed (1 s/6 s) when exposed to 100 ppm n-propanol at 220 °C. Furthermore, the sensor demonstrates a low limit of detection (LOD) of 432 ppb, strong repeatability, good long-term stability (80 days), and excellent anti-humidity properties (S 84 % /S 33 %  ≈ 0.84). The enhanced gas sensing performance is primarily attributed to the formation of ZnSnO 3 /ZnO n-n heterostructures, the increase in oxygen vacancies, and the presence of ordered open porous structures. Consequently, ZnSnO 3 /ZnO heterostructures show significant potential for the detection of n-propanol gas in practical applications. This work also presents a promising strategy for the development of homogeneous/heterogeneous materials with a 3D open porous structure, which can be applied in surface-related fields.