Rapid and Sensitive Detection of 2-Ethylhexanol Vapor Utilizing Mesoporous Neodymium-Doped Indium Oxide for Real-Time Monitoring of Overheated Electrical Cables

Rapid and sensitive detection of 2-ethylhexanol vapor, a critical indicator of overheating in electrical cables, is essential for the early warning of potential electrical fires. However, traditional chemiresistive gas sensors are inadequate for real-time detection of 2-ethylhexanol owing to its chemical stability. Herein, a chemiresistive gas sensor based on mesoporous Nd-doped In₂O₃ is designed for rapid detection of ppb-level 2-ethylhexanol vapor. The sensor exhibits a high response (22.8@1 ppm), excellent sensitivity (4.7 ppm^-1), a short response time (29 s), and a low detection limit (760 ppb). After Nd doping, the response of the mesoporous Nd-doped In₂O₃ sensor is approximately 20 folds higher than that of the In₂O₃ sensor. Furthermore, a wireless sensing device has been developed to enable real-time monitoring of cable overheating. The outstanding sensing performance can be attributed to neodymium doping within the mesoporous framework, which enhances the accessibility of active sites on the interface of sensing materials, increases the concentration of surface-adsorbed oxygen at the gas-solid interface, and improves the adsorption capacity for 2-ethylhexanol. This work showcases an efficient semiconductor metal oxide gas sensor capable of rapidly and sensitively detecting parts per billion levels of 2-ethylhexanol induced by the overheating of electrical cables, demonstrating significant potential for early warning of electrical fires.