Gas sensing performances of commercial carbon fibers functionalized by NiO/SnO2 composite

Abstract Commercial carbon fibers (CFs) were functionalized with NiO/SnO 2 composite powders via a simple liquid phase deposition method followed by heat treatment and the influences of CFs content on the micro-structure and gas sensing performances of the CFs/NiO/SnO 2 gas sensor were investigated. The results indicate that the distinctive one-dimensional CFs overlapped with each other, forming a large number of pores inside the CFs/NiO/SnO 2 composite, which increases the effective reaction area between sensitive materials and target gases greatly. The CFs/NiO/SnO 2 gas sensor with 0.5 wt% CFs exhibits a good sensitivity, selectivity and excellence response-recovery characteristic to formaldehyde at lower operation temperature of 170 °C. Notably, the detectable concentration of HCHO is as low as 1 ppm, indicating a certain application prospect in formaldehyde detection. And the electronic transmission bridge mechanism is performed to explain the gas sensing mechanism, which plays a certain role in the functional application of CF.