The present investigation deals with the NO2 gas detection via nanostructured zinc oxide (ZnO) thin films harvested over a glass substrate via a simple and facile successive ion layer adsorption and reaction (SILAR) approach. ZnO nanostructured thin films are developed by different SILAR cycles (ZnO:15, ZnO:30, ZnO:45, ZnO:60). The physicochemical, optical, and morphological properties of prepared thin films are explored by various characterization techniques. The phase purity and grains size are confirmed by X‐ray diffraction (XRD) and Scherrer formula, which reveal the hexagonal phase structure with variant grain size (≈16–21 nm). The surface morphology of deposited films shows the well‐dispersion of ZnO nanoparticles, which is picturized by field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), attenuated total reflectance (ATR). UV–Vis and FTIR spectroscopy elaborates on the optical properties and functional groups of ZnO films, respectively. Further, the sensing ability of ZnO thin films is studied with different concentrations (50–250 ppm) of NO2 gas in the span of 50 ppm by recording the resistance transient. The ZnO:30 thin‐film displays an enhanced gas sensing response of 1.42 GΩ at 100 °C compared to other synthesized films and at different temperature ranges. The ZnO:30 film shows the highly selective response toward the NO2 gas compared to other interference gas species. Thus, the present study highly recommends the investigated method for the ZnO thin film formation to be employed toward NO2 gas sensing.

Present study we reported the structural, optical and functional group study of copper-doped zinc oxide nanoparticles (NPs) synthesized by chemical co-precipitation method. In this study doping concentration of copper (0.2, 0.4, 0.6) was incorporated in zinc oxide. All the synthesized samples were characterized by X-ray diffraction (XRD) as well as Fourier transform infrared (FTIR) and studied the photo luminance (PL) property. XRD study confirms the structural and purity of ZnO and Cu doped ZnO nanoparticles. The average grain size of pure ZnO was calculated by Scherrer formula and it varied according to doping concentration from 25.10 to 20.26 nm. The average grain size of pure ZnO was decreased for Cu-doped samples. The presence of functional groups and chemical bonding were confirmed by FTIR. Due to the doping concentration of copper the structural, functional group and photo luminance properties of ZnO was changed drastically.

In this study, Mg doped ZnO thin films were successfully prepared using the modified SILAR approach throughout various numbers of deposition cycles. XRD data shows the prepared films have a ZnO wurtzite hexagonal structure. The crystalline size and crystallinity were found to be increased by increasing the number of deposition cycles. FESEM showed there are nanoparticles and nanorods on the surface, with random distribution in the case of the sample synthesized with 30 cycles, while the agglomeration of nanoparticles to form a maize-like structure and flower-like morphology was predominant in the case of the sample with 40 cycles. The UV-VIS transmittance spectra showed a decrease in transmittance by increasing the number of deposition cycles, and the increment of energy band gap by increasing the number of deposition cycles was found. The response of the samples towards NO2 gas at 200 °C operating temperature was found to be enhanced in the case of the sample prepared at 40 cycles as compared to the sample prepared at 30 cycles.

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In the present work, synthesis of CuO, ZnO and CuO/ZnO Nonocomposites and their properties have been investigated. CuO, ZnO and CuO/ZnO NC were synthesized using the co-precipitation method. The nanocomposite materials were structural, morphological and optical properties characterized by X-ray diffraction (XRD), Field Emission Scanning Electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), UV-Vis Spectroscopy. The results of the XRD analysis exhibited that the pure CuO, ZnO and CuO/ZnO NC has a nanometer size with an average of 15.19 nm. The UV-vis analysis showed that the CuO, ZnO and CuO/ZnO NC has a band-gap of 3.31 and 2.35 eV. FTIR investigation revealed that the vibration of ZnO was observed at 561 cm-1 whereas CuO was at 602 cm-1 and composites 612 cm-1. The FESEM-EDX analysis revealed that the ZnO has a hexagonal structure whereas the CuO has a monoclinic structure. HIGHLIGHTS Present investigation deals with CuO, ZnO, and CuO/ZnO composites nanoparticles harvested as Co-Precipitation Method Various characterisation techniques were used to investigate the structural, optical, and morphological features of produced nanoparticles composites Investigation the effects of different properties of the CuO, ZnO and CuO/ZnO composites nanoparticles as well as Co-Precipitation method GRAPHICAL ABSTRACT