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NiO thin films were grown systematically using the nebulizer spray pyrolysis (NSP) method with different additions of Ag 1%, 2%, and 3% respectively. A photodetector was fabricated using NiO:Ag thin films. The structural, morphological, compositional, optical, and electrical properties of NiO:Ag thin films were studied as a function of Ag addition. XRD studies show a gradual reduction in the intensity and the broadening with Ag addition, which confirms the formation of nanoparticles. Ag phase has been formed after 3% of Ag addition. Compositional studies using EDS confirms the presence of all the elements. The energy band gap of films is found to be in the range 3.25–3.45 eV with an Ag addition of 1–3%. I–V characteristics and photoresponse of photodetectors were recorded under UV light illumination. The parameters of a photodetector such as external quantum efficiency, responsivity and detectivity were calculated. The observed photo responsivity increases with an increase of Ag (1%) and decreases further higher Ag concentrations.The maximum responsivity is observed for the NiO film with 1%Ag. The photoresponse of all samples confirmed the stable and reproducible characteristics such as external quantum efficiency, responsivity and detectivity.The enhanced properties observed for 1% of Ag-doped film may find applications in the fabrication of optoelectronic devices. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) of ZnS with different weights of CTAB (cetyltrimethylammonium bromide) have been successfully synthesized by microwave assisted co-precipitation method. The x-ray diffraction patterns exhibited cubic phase crystal structure with crystallite size of ~3 nm. The morphological studies of the grown samples have been investigated using Scanning electron microscopy (SEM). Diffused reflectance spectra were employed to calculate energy gaps for prepared samples using Kubelka-Munk theory, and the values were in the range of 3.59–3.64 eV. Raman spectra confirm the synthesis of ZnS nanoparticles at all CTAB contents and it contains two major Raman modes at ~264 and 346 cm−1 related to TO and LO modes which are shifted to lower wavenumbers indicates phonon confinement in the final products. The variations in the dielectric constant, ε' and dielectric loss were calculated. The values of ε' is higher in the low frequencies, whereas it is found almost stable between 1 MHz and 5 MHz and is increasing at higher frequencies. The dielectric study reveals that the samples possess high values of dielectric constant which are between 27 and 35 and low loss values. The electrical conductivity is noticed to be increased with increasing the frequency and also noticed to be varied with varying the CTAB content in ZnS. The synthesized low dimension NPs, high energy gap and dielectric constant and low loss values signifies that the prepared NPs are suitable for optoelectronics. [ABSTRACT FROM AUTHOR]