Tailoring porous structure composed of nano indium oxide and nano zinc ferrite to be act as an efficient humidity sensor

Abstract In this work, we reported the synthesis of a high-performance humidity sensor based on an indium oxide/zinc ferrite nanocomposite. The composite was prepared by hydrothermal technique, which resulted in a homogenous nanostructure. The structural and morphological characterizations were performed using XRD, FTIR, UV-Vis, SEM, EDX, TEM and BET techniques, confirming the formation of In₂O₃/ZnFe₂O₄ composite with well-defined particle sizes in the nanometer scale. The humidity sensing performance was evaluated in a wide range of relative humidity, from 11% up to 97%. The optimal testing frequency was determined to be 100 Hz. The results demonstrate that the prepared nanocomposite exhibits an excellent dynamic response characteristic. Also, the sensor demonstrated good repeatability in its response, showing stable performance across cycles. Furthermore, due to the porosity and high surface area, water vapor absorption and desorption occurred rapidly in the nanocomposite. These results indicate that In₂O₃/ZnFe₂O₄ nanocomposite is a promising candidate for humidity-sensing applications.