Fabrication and Enhanced n-Butanol Gas-Sensing Performance of Au-modified SnO2/ZnO Nanoflowers

Developing high-performance n-butanol gas sensors is very important for production safety and employee health protection. Here, Au-modified SnO2/ZnO nanoflowers with high response and selectivity toward n-butanol have been fabricated using a two-step routine involving solvothermal and photochemical methods. The results show that Au-modification effectively enhanced the sensing performance of the SnO2/ZnO, and the response (88.56) of a 0.9% Au-SnO2/ZnO-based sensor to 100 ppm n-butanol at 240 degrees C was 2.3 times as much as SnO2/ZnO nanoflowers, exhibiting a fast response (3 s) and recovery time (86 s). The response to n-butanol at 240 degrees C is 2.2, 2.3, 2.6, 2.7, 3.8, 4.3, and 4.4 times that of ethanol, triethyamine, isopropanol, methanol, acetone, xylene, and ammonia, respectively, demonstrating a remarkable selectivity for n-butanol over other gases. Its sensing mechanism to n-butanol can be well attributed to the interface depletion layer and electron migration in the heterojunction. Therefore, the sensor has important application prospects in the safety management of n-butanol-related production and transportation.