Synthesis of 1D SnO2 nanorods / 2D NiO porous nanosheets p-n heterostructures for enhanced ethanol gas sensing performance

The microstructure and composition of materials have significant impacts on the gas sensing performance of sensors. In this work, a well-constructed 1D SnO2 nanorods/2D NiO porous nanosheets heterostructure were successfully prepared for the detection of ethanol gas. The SnO2 nanorods with a diameter of 10-15 nm uni-formly grew on the surface of NiO nanosheets, increasing the number of active sites. The space charge region formed at heterointerfaces controlled electron transfer, benefiting for improving sensor response. Gas test results showed that, at the optimum operating temperature of 300 C, NiO/SnO2 (Ni:Sn = 1:0.5) reached a high response of 25.7 to 100 ppm ethanol, which was about 15 times higher than pure NiO (1.65). In addition, the NiO/SnO2 displayed a fast response-recovery speed, good selectivity, and excellent long-term stability. The enhanced gas sensing mechanism of NiO/SnO2 was proposed by analyzing the surface chemical states, surface area, and electronic structure of materials.

Automated summary

The microstructure and composition of materials have significant impacts on the gas sensing performance of sensors. In this study, a well-constructed heterostructure of 1D SnO2 nanorods and 2D NiO porous nanosheets was successfully prepared for the detection of ethanol gas. The heterostructure exhibited increased number of active sites and controlled electron transfer, resulting in high response and fast response-recovery speed.