The combination of semiconductor heterojunction with rGO is recognized to be a promising method to improve the sensing performance in gas sensor. The 3.7 wt% rGO-NiO-BiVO₄ composite was synthesized successfully by a simple hydrothermal and metal organic decomposition method. The gas-sensing tests reveal that the highest response of the ternary composite is 4 times and 8 times higher than the rGO-NiO junction and the NiO alone, respectively towards 2 ppm NO₂ at 60 °C and the ternary composite exhibits rapid response. Moreover, the composite to NO₂ exhibits the highest response among all tested gases, such as CO, toluene, ethanol, NH₃ and formaldehyde, that is, the composite towards NO₂ has excellent selectivity. The improvement is attributed to the effective electron transfer at interface of heterojunction and to the increase of surface area and surface defect due to rGO loading. The work has reference value for improving gas sensing performance of p-type semiconductor.

半导体异质结与rGO的结合被认为是提高气体传感器传感性能的一种有前途的方法。通过简单的水热和金属有机分解方法成功合成了3.7 wt％的rGO-NiO-BiVO ₄复合材料。气敏测试表明，三元复合物在60°C下对2 ppm NO ₂的最高响应分别比rGO-NiO结和单独的NiO高4倍和8倍，并且三元复合物表现出快速响应。此外，在所有测试气体（例如CO，甲苯，乙醇，NH ₃和甲醛）中，复合材料对NO _2的响应最高，即复合材料对NO ₂的响应具有极好的选择性。改善归因于异质结界面处的有效电子转移以及归因于rGO负载的表面积和表面缺陷的增加。该工作对提高p型半导体的气敏性能具有参考价值。