Hierarchical WO<sub>3</sub> Nanofibers for Ultrasensitive Gas Detection via Pore-Creating and Inner Anchoring Silver Nanoparticles
Chuanxuan Zhou, Shaowei Li, Fuchao Yang, Zhiguang Guo
Abstract
Ultrasensitive detection of triethylamine (TEA), a characteristic volatile in seafood, is particularly important for food safety and human health. The preparation of nanosensing materials with special structures is an important step toward high-performance TEA detection. This study introduces a novel method of loading noble metal catalysts onto the inner walls of WO 3 macroporous nanofibers (MNFs) to prepare high-performance TEA sensing materials by using core–shell nanospheres with glucose-coated Ag particles as sacrificial templates. After high-temperature calcination, WO 3 MNFs loaded with Ag particles on the inner wall (Ag-WO 3 MNFs) were obtained by decomposition of organic components and oxidation of W precursors. The abundant porous structure, large number of oxygen vacancies and strong sensitizing effect of Ag particles give Ag-WO 3 MNFs excellent sensing performance. Gas sensing measurements reveal that 1.5% Ag-WO 3 -based sensor responds to 1 ppm TEA with a response time of 1 s, a response value as high as 1054.17 ( R a / R g ), and a low detection limit (12.8 ppb) at 185 °C. The adsorption process of gas molecules on the surface of Ag-WO 3 MNFs is revealed using density-functional theory (DFT) calculations. The integration of this distinctive design concept with an in-depth mechanistic investigation offers a novel strategy for engineering high-performance TEA sensing materials.