Porous carbon nanofibres with humidity sensing potential

Based on polyacrylonitrile (PAN)/poly(vinylpyrrolidone) (PVP) electrospun precursor fibres, this work developed an efficient and cost-effective pore generation approach to produce porous carbon nanofibres (PCNFs) with humidity sensing potential. PAN/PVP fibres were treated by a blend of N, N-dimethylmethanamide (DMF) and water (H2O) to generate a highly porous structure. Through the collective effects of crystallisation of PAN and dissolution of PVP, the solid PAN/PVP fibres were transformed to be porous ones with higher surface areas. Carbon nanofibres (CNFs) and PCNFs were manufactured from untreated and treated PAN/PVP fibres following air stabilisation at 260 °C and argon carbonisation at 1000 °C. Surface area and pore volume are both increased on PCNFs. To obtain a flexible carbon film for humidity sensing, the cellulose fibres were then combined with PCNFs and CNFs. After characterising the sensing performance of composite films in dynamic and static situations, experimental results demonstrated the PCNFs film's promising future as a stable and reactive humidity sensor.