The synthesis of a Cu0.8Zn0.2Sb2–polyacrylamide nanocomposite by frontal polymerization for moisture and photodetection performance

Abstract

Herein, the preparation of a Cu_0.8Zn_0.2Sb₂AAm–polymer nanocomposite synthesized via a frontal polymerization technique is reported, together with its humidity sensing and photoconductive behaviour. The surface texture was examined using scanning electron microscopy (SEM) analysis. X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies confirm the crystallinity of the as-fabricated nanocomposite thin film based sensing element. The surface area, particle size, optical absorbance, and thermal stability of the as-fabricated thin film were successively investigated using Brunauer–Emmett–Teller (BET) analysis, particle size analysis, ultra-violet absorption studies, Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and differential scanning calorimetric (DSC) analysis. The humidity sensing characteristics were also investigated based on the capacitive performance of Cu_0.8Zn_0.2Sb₂AAm film when exposed to moisture. The average sensitivity (S) of the as-fabricated sensor was found to be ∼168.477 pF/% RH at an optimum frequency of 20 Hz. The sensor exhibited rapid response and recovery times of 4.6 s and 5.6 s, respectively, with persistent stability of 96% after 60 d. Thus, the Cu_0.8Zn_0.2Sb₂AAm polymer-based capacitive humidity sensor shows its potential for reliable and safe use in the detection of humidity levels, as well as for photoconduction.