Enhanced NOx Gas Sensing Properties of Ordered Mesoporous WO3/ZnO Prepared by Electroless Plating

A kind of novel n-n combined ordered mesoporous WO3/ZnO (OM-WO3/ZnO) sensor are successfully fabricated in this study. A soft-template method is used to synthesize the ordered mesoporous ZnO matrix. Surfaces of the ZnO matrix are innovatively modified using silane coupling agent (mark as: OM-ZnO-Si), and then a layer of WO3 film is assembled on the surfaces of the OM-ZnO-Si by chemical plating method for the first time, and the OM-WO3/ZnO material is obtained. The prepared OM-WO3/ZnO sample shows a kind of regular hexagon-sheet structure. The prepared OM-WO3/ZnO sensor shows the much better response, much shorter response time, much lower detection limit, and the more excellent selectivity toward NOx gas. When oxynitride (NOx) gas concentration is 100 ppm, the response reaches to 82.64%, the response time is only 6 s at room temperature. The detection limit is only 0.01 ppm. The unique loose porous structure and the synergistic effect of the n-n heterojunction structure endow the prepared OM-WO3/ZnO material with the superior gas sensing properties. The n-n combined OM-WO3/ZnO material shows the vast development potential in gas sensor field.