Formation of pure and Sn-doped ZnO thin films via sol–gel spin coating technique: a study on structural, topographical, and sensing properties
摘要
In the present investigation, chemical-based sol–gel spin coating technique has been employed for the synthesis of Zn1−xSnxO thin films and modifying its structural, morphological, and humidity sensing properties with increasing Sn-doping concentration (x = 0.00, 0.02, 0.04, and 0.06 wt.%). The Zn1−xSnxO thin-film XRD patterns revealed the wurtzite hexagonal crystal structure. Through utilizing X-ray diffraction (XRD), the average size of the crystallite of Zn1−xSnxO thin films was calculated and found to be in the range of 21.08, 25.53, 28.35, and 36.57 nm. Investigation of the topological architecture of Zn1−xSnxO with (x = 0.00, 0.02, 0.04, and 0.06 wt.%) thin films using AFM micrographs revealed that nanorods-like topography has been modified into nanosheets that are uniformly dispersed across the surface of the films. The AFM micrograph of 4 wt% Sn-doped ZnO sample revealed that nanorods-shaped morphology has been altered to a nanosheet structure resembling nanorods with dense packing. Additionally, increasing the Sn-doping concentration in ZnO NPs from 0 to 6 wt% results in lesser hysteresis loss, less aging impact, and excellent sensitivity in the range of 5.82 M/%RH to 11.05 M/%RH, respectively. Sensitive materials are less expensive as the concentration of Sn doping increases, making them an excellent choice for humidity sensors.