Abstract The objective of this work is to synthesize new set of nanoceramics that improves structural integrity and dielectric performance while maintaining the desired characteristics of ZnO with the introduction of regulated Ni-doping. By using the sol-gel process, Ni-doped ZnO nanoceramics were successfully synthesized. Zn1–xNixO (x = 0, 0.05, 0.01, 0.15) wt % of Ni in to Zn precursor salts were added. Doping levels are considered to be low to moderate level, which typically lead to considerable changes in structural, optical, morphological and dielectric properties without modification of the nature of host ZnO. Higher concentrations greater than 15 % can result in the precipitation of isolated Ni or NiO phases which may negatively influence uniformity and consistency of the doped material. By using XRD for structural study, phase purity and the hexagonal wurtzite structure were confirmed. The integration of Ni2+ ions into the ZnO lattice is indicated by the change in lattice parameters and bond length for the Ni-doped ZnO sample. Samples follow almost same c/a ratio of an average of 1.601. An increase in “Ni” content results a decrease in crystallite size. Average crystallite size has been calculated ranging from 43.88 nm to 17.01 nm for ZnO to Zn0.85Ni0.15O samples. According to SEM analysis, the grains of the samples are uniformly dispersed. When the produced NPs were examined for purity using EDAX analysis, it was found that the beginning stoichiometries and the chemical composition of Zn, Ni, and O agreed well. The development of the ZnO phase was verified by the presence of a peak at 523 cm−1 in the FTIR spectra. According to the findings of X-ray photoelectron spectroscopy (XPS), Ni was observed to be present in the ZnO lattice in the form of Ni2+.The Koops phenomenological theory and the Maxwell-Wagner model provide an explanation for the observed dielectric behaviour. It is noted that for pure ZnO, the dielectric constant and dielectric loss have maximum values, whereas for doped samples, these values decreases. Our sample is suitable for high frequency device application due to a negligible dielectric loss of 0.047 at 15 % Ni concentration in the high-frequency region. Ni-doping affects AC conductivity. At 10 MHz, Zn0.9Ni0.1O has the highest AC conductivity (2.654 × 10⁻⁴ (Ω cm)⁻1), while Zn0.85Ni0.15O shows a lower value (1.048 × 10⁻⁴ (Ω cm)⁻1), indicating a balance between doping level and grain boundary influence on conduction. The impedance study reveals that just one semicircle in all samples, indicating that the influence of grain boundaries is more significant than the contribution of individual grains.
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