Ultrasensitive self-powered photoelectrochemical detection of methane based on a coaxial integrated carbonene fiber

Methane monitoring is imperative and crucial for the life and property safety and environmental protection. However, challenges remain pertaining to high sensitivity, exceptional stability as well as superior structural flexibility and robustness of sensing platforms. To address these issues, herein, a facile and effective strategy was proposed by constructing a coaxial integrated fiber-shaped self-powered photoelectrochemical methane sensor with a superflexible yet robust carbon nanotube (CNT) fiber as the inner electrode, continuous and thin gel as the electrolyte interlayer, and rough and transparent hybrids embedded by Ag nanowire (AgNW)-bridged interconnected conductive network as the outer electrode. The unique architectural features enabled a rapid ion/electron transport, effective methane adsorption, convenient light absorption and outstanding structural stability, thereby boosting a wide linear range (5-170 ppm) and a low detection limit (0.8 ppm). Moreover, favorable selectivity and perfect working performance during bending were available as expected. This research has shed light on new strategies for designing and fabricating photoelectrochemical sensors towards highly sensitive gas monitoring.