Highly responsive n-butanol gas sensor based on double-shell ZnO hollow microspheres
Yuan Qu, Ziwen Ding, Xiao–Tong Yuan, Feiyu Zhang, Ke Xu, Lu Xiang, Song Liu, Si‐Qi Li, Wei Ji
Abstract
The fabrication of gas sensors based on metal oxide semiconductors (MOS) with high sensitivity and low detection limits is a crucial research domain. Modulation of microstructural features is a critical strategy to enhance gas sensing performance, owing to its controllability and inherent design flexibility. The double-shell structure amplifies active surface sites and nested effects, further heightening gas-sensor interaction for escalated adsorption efficiency and reaction rates. In this paper, we fabricated hierarchical double-shell ZnO hollow microsphere (D-ZnO) sensors via a scalable technique, incorporating uniformly spherical carbon templates. These D-ZnO-based sensors demonstrated a high response (32.42) to 100 ppm n-butanol and achieved a low detection limit (DL) of 96 ppb at the optimized temperature of 240 °C. Such excellent gas sensing performance of D-ZnO can be attributed to the unique spatial structure of hierarchical double-shell for the modulation of gas diffusion pathways and collision frequency.