Ultra-sensitive SnO₂ aerogel in nano-trace ethanol detection

SnO₂ is a charming contributor to sensors, while the intrinsic deficiencies, like facile conglomeration, hard stimulation, and poor stability, limit its potential prospects. The SnO₂ aerogel (SA) is proposed through an achievable fabrication, effectively solving the difficulties and exhibiting a satisfactory ability in ethanol detection. The SA450 behaves as the spearhead, which owns the narrowest bandgap of 3.2 eV and the largest double-layer capacitance of 559 μF/cm², symbolizing the most prone electronic transitions and active sites. Besides, SEM, TEM, and AFM are served to obtain the nanoparticle size and the rough surface. The SA450 exhibits an outstanding sensing ability at 150 ℃, and the DFT calculation is taken as evidence. Interestingly, the SA0 without calcination can exhibit a satisfying SERS detection towards 4-MBA, which applies to explosive detection. Finally, the bandgap structure and response process are discussed. This work introduces a brand-new preparation of metal oxide semiconductors (MOSs), overcoming plenty of aporias in gas sensors and simultaneously producing the SERS response, which can lead to a fresh direction for sensing materials.