Electrospun Vanadium Pentoxide (V2O5) Nanofibers for Enhanced Humidity Sensing

Adequate humidity monitoring is crucial for many industrial and consumer applications. Among various moisture-absorbing materials, 2D materials are potential contestants for fabricating humidity sensors owing to their fascinating ultra-high surface-to-volume ratio, abundant active sites, and large carrier mobilities. In this work, vanadium pentoxide (V₂O₅) nanofibers (NFs) produced by a facile electrospinning method using VO(acac)2 10% Polyacrylonitrile/Dimethylformamid are showcased for humidity sensing. The annealing temperature-dependent (400–600 °C) variations in morphology and composition of the electrospun V₂O₅ NFs are studied by structural and physicochemical characterization methods. Subsequently, the V₂O₅ NFs are effectively used for humidity sensing at room temperature (RT). It is demonstrated that the optimum RT humidity response and sensitivity of the NF sensor are obtained at an annealing temperature of 500 °C with a high surface area of 14.8 m²g⁻¹ containing large porous fibers ranging from 200 to 500 nm diameter. The synthesized V₂O₅ NF sensor exhibits high sensitivity to water at RT (max. 1.427 at 90 %RH), excellent linearity, wide range (10–90%RH), and quick response and recovery times. This work sets a benchmark for designing novel V₂O₅-based RT humidity sensing devices.