Acetone vapor sensing characteristics of Cr-doped ZnO nanofibers

Various amounts of chromium (Cr) were added to zinc oxide (ZnO) nanofibers (NFs) by electrospinning (ES), and pyrolysis was performed at 600 °C to form pure and Cr-doped ZnO NFs. The morphology, structure and optical properties of the NFs were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible spectroscopy (UV-Vis). It was found that the structure of the NFs became rougher, and the diameter decreased with the increase of the Cr content. The maximum diameter of 150 nm was observed for 4 w% Cr-doped ZnO NFs. The bandgap energy decreased as the doping concentration increased. The gas-sensing properties of the Cr-doped ZnO NFs were investigated by measuring their response to acetone vapor. The results indicate that among all the samples, the 4 w% Cr-doped ZnO NFs exhibited the best sensing response to acetone vapor, with a response of 88.65–50 ppm acetone vapor. The response and recovery times were approximately 80 s and 55 s, respectively. Further, the Cr-doped electrospun NFs showed exceptional selectivity and stability, indicating their potential for high-performance gas sensor fabrication. This work reports an intriguing cost-effective lab designed gas sensor to investigate the sensing properties of pure and Cr-doped ZnO NFs.