In-situ growth of well-ordered ZnO nanowire-networks with interconnected junctions for enhanced SO2 gas sensing properties

SO2 gas sensors based on ZnO nanostructures under wild conditions are used widely yet an insufficient electron transfer channels limit the enhancement of the gas-sensing performance. Herein, we report well-ordered ZnO nanowire-networks with interconnected junctions via a simple solution-processing method by adjustment of additive to produce remarkable SO2 gas-sensing performance: low detection limit of 200 ppb, fast response-recovery speed (102 and 58 s) and high response value (8.28) to 10 ppm SO2 at work temperature of 200 degrees C. The 3D net-work ZnO arrays with fully interconnected junctions, rich oxygen vacancies, and high conductivity are confirmed. Furthermore, the SO2 gas mechanism related to the interjunctions is also clarified. This research offers a novel strategy for designing high performance ppb-level SO2 gas sensor.