Morphology genetic 3D hierarchical SnO₂ microstructures constructed by Sub 5 nm nanocrystals for highly sensitive ethanol-sensor

SnO2 is widely used for ethanol-sensing applications due to its excellent physicochemical properties, low toxicity and high sensitivity. However it a challenge construct 3D-hierarchical structures with sub 5 nm primary grain particle, which the optimized size ethanol sensor. Herein, genetic tri-level hierarchical microstructures are synthesised by conversion of 3D SnS2 flowers assembled ultrathin nanosheets. The nanosheets morphology converted porous nanoparticles during calcination process. When detection ethanol, sensor exhibits sensitivity 0.5 ppm (Ra/Rg = 6.8) gas-sensing response 183 100 ppm) short response/recovery time (12 s/11 s). gas sensing performance much better than that previous reported SnO2-based sensors. highly attributed large surface area derived from recrystallization volume changes, offers more active sites SnO2. Furthermore, flower-like structure enhances stability materials beneficial mass diffusion dynamics ethanol.