Single-phase high-entropy oxide-based chemiresistor: Toward selective and sensitive detection of methane gas for real-time applications

Detecting methane (CH4) with good selectivity is one of the most important safety precautions to prevent catastrophic incidents in current industrial environment. Detection small molecular size, inert and nonpolar characteristic gases at trace levels using chemiresistive technique room temperature still challenging because weak adsorption between gas sensing material. Therefore, we fabricated a single-phase high entropy oxide based chemiresistor tested it towards various several hydrocarbons temperature, but sensor displayed higher CH4 than other gases. Further, characteristics revealed significant response gas, recovery time, long-term stability, an experimental detection limit 25 ppm. Besides, as-fabricated low-cost, size consumes 50 nW power, much lower commercialized light-based sensors. As proof concept, was utilized measure real-time atmosphere. The reflected similar controlled environment recovered without carrier gas. This facile approach sheds light on rational design high-entropy oxides, paving way for mass production commercialization ultra-trace sensors superior capability.