Recent advances in NiO-based gas sensors have been reported, but high working temperatures and dry conditions are usually required. Herein, we report the volatile organic compound (VOC) sensing performance of… Click to show full abstract
Recent advances in NiO-based gas sensors have been reported, but high working temperatures and dry conditions are usually required. Herein, we report the volatile organic compound (VOC) sensing performance of flower-like (FL) NiO hierarchical structures modified with reduced graphene oxide (RGO) sheets under high humidity. RGO/FL-NiO composites were synthesized by a simple and template-free microwave-assisted hydrothermal method and subsequent calcination at 250 °C. The VOC-sensing properties were investigated for several VOCs, such as acetone, ethanol, methanol, m-xylene, and toluene, at 90% relative humidity. The RGO/FL-NiO composites exhibited a decrease in the optimal operating temperature and enhanced methanol responses compared to pure FL-NiO. In addition, the 5% RGO/FL-NiO composite exhibited the highest response of 61.51% to 100 ppm of methanol at 180 °C, which was 1.4–9.9 times superior to responses to other VOCs, indicating the sensor's great selectivity. The improved methanol sensing properties could be attributed to the NiO/RGO heterointerface.
               
Click one of the above tabs to view related content.