Au nanoparticles decorated ZnIn2S4/WO3 core-shell heterostructures as highly sensitive and selective ethylene glycol gas sensors

Ethylene glycol (EG) is extensively utilized as anti-freezer and deicer, which would bring potential health risk under unintentional exposures especially with hazardous inhalation of EG aerosols or vapors. In this study, ZnIn 2 S 4 (ZIS)/WO 3 core-shell nanofibrous heterostructure loaded with optimized Au nanoparticles (NPs) was prepared for superiorly sensitive and selective EG gas sensing. The ternary Au/ZIS/WO 3 heterostructures exhibited an excellent response ( Ra/Rg =98.92) to 50 ppm EG, demonstrating an enhancement of 3.5 times compared to the binary ZIS/WO 3 , and a substantial improvement of 59.5 and 24.1 times compared to pure WO 3 and ZIS, respectively. The ternary Au/ZIS/WO 3 heterostructures also possessed an extremely low detection limit of 6 ppb, as well as excellent selectivity , repeatability, and long-term stability. This exceptional gas sensing performance can be attributed to its distinctive ternary Au/ZIS/WO 3 heterostructures with high specific surface areas . This unique structure not only facilitate the activation of abundant active oxygen species, but also promote the spillover effect of Au and enhance effective electronic distribution, thereby providing more EG adsorption sites, which was confirmed by density functional theory calculation. The synergistic effect arising from the metal-semiconductor interface and the core-shell heterostructure presents a novel avenue for advancing high-performance sensor technologies.