Facile depositing strategy to fabricate a hetero-affinity hybrid film for improving gas-sensing performance.

A novel co-spray method was proposed to fabricate a reduced graphene oxide (rGO)-poly (3-hexylthiophene) (P3HT) hybrid sensing device utilizing immiscible solution for ammonia detection at room temperature. The spectrum and Scanning Electron Microscopy (SEM) results revealed uniformly crimped morphology and favorable π-π interaction for the hybrid film. The hybrid film-based sensor showed obviously enhanced ammonia sensing performance, such as increased response, reduced response time, and reinforced sensitivity, in comparison to bare rGO, P3HT, and traditional rGO/P3HT layered film-based sensors, which could be attributed to an adsorption energy barrier and the p-n heterojunction effect. The synergetic strengthened sensing mechanism is discussed. Meanwhile, recovery ratio was introduced to evaluate the abnormal baseline drift induced high-response behavior. The excellent sensing properties of the hybrid sensor indicate that the co-spray method could be an alternative process for the preparation of hetero-affinity hybrid films or functional devices.