TS Science

This work presents the synthesis of Sn doped NiO nanostructures with varying doping concentrations (0 %, 1.25 %, 2.5 %, 5 %, and 10 %) using a hydrothermal method, aiming to explore the impact of Sn incorporation on their structural, optical, and photoelectrical behavior. X-ray diffraction (XRD) patterns confirmed the retention of the face-centered cubic phase across all samples, with a notable reduction in crystallite size from 16.02 nm (undoped) to 11.90 nm (10 % Sn-doped), attributed to the partial substitution of Ni²⁺ by Sn⁴⁺ ions. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) revealed a progressive decrease in particle size and improved morphological uniformity as the Sn content increased. UV–Vis spectral analysis exhibited a redshift in the absorption edge with increasing Sn concentration, corresponding to a narrowing of the optical band gap from 3.16 eV to 2.68 eV, which facilitates enhanced photon absorption. Under UV illumination, the photocurrent response improved significantly, with the 10 % Sn-doped sample demonstrating a peak photocurrent of 25.09 nA at 3 V bias, compared to 16.28 nA for the pristine NiO. The highest photosensitivity and photoresponsivity were recorded for the 10 % Sn-doped sample, reaching 0.16 μA/W. These results underscore the potential of Sn doping as a viable strategy to enhance the photoelectrical performance of NiO-based nanostructures for optoelectronic device applications, particularly in UV photodetection technologies.