Interfacial Donor−Acceptor Nanofibril Composites for Selective Alkane Vapor Detection

The detection of alkane vapors has strong implications for safety, health, and the environment. Alkanes are notoriously difficult to detect because of their chemical inertness at room temperature. Herein, we introduce a tunable photoinduced charge transfer strategy to selectively detect alkane vapors under ambient condition. A unique donor− acceptor nanofibril composite comprising a compatible interface was fabricated, which is preferential for alkane adsorption. Then the enhanced adsorption disrupts the charge transfer across the interface and decreases the photocurrent, enabling the design of alkane gas sensor. We demonstrate a critical relationship between the tunable donor−acceptor interface and alkane response. The composite sensor is able to provide specific distinction between different alkanes based on their kinetics of the response profiles, and outstanding general selectivity against the common polar solvents. The work described herein may provide a basis for a new type of sensing material for detecting inert chemicals at room temperature.