Fabrication of 3D Multi-Edges Cube Porous SnO2/ZnO Composites as High-Performance NOx Gas Sensor

In this study, a kind of novel porous 3D multiedges cube SnO2/ZnO composite with n-n heterojunctions was prepared through a facile hydrothermal route. A kind of ordered mesoporous ZnO must be used as precursor in the hydrothermal reaction which was fabricated by soft-template method. The surfaces of the 3D multi-edges cube SnO2/ZnO composite were distributed with ordered mesoporous of 10.2 nm. The grain refinement effect was happen by SnO2, it led to the specific surface area of thematerial reached to 135.641 m(2) center dot g(-1), which was nearly 3.9 times of ZnO matrix. At roomtemperature (25 degrees), the 3Dmulti-edgescube SnO2/ZnO nanomaterial showed excellent gas response to NOx, whose response to 100 ppm NOx reached 60.41 +/- 0.5%, the response time was only 2 s, and the detection limit was 0.2 ppm. It broke the tradition that SnO2/ZnO composite showed gas response to NOx only in relatively high temperatures.