The study aims to contribute valuable insights into the potential applications of the photocatalyst, particularly in the realms of sustainable energy and environmental remediation. Here, Zn-doped NiO nanoparticles with different mole percentages of zinc ingredients are produced and analyzed. Synthesized Zn-doped NiO nanoparticles were evaluated structurally, optically, morphologically, elementally, and photocatalytically. According to X-ray diffraction analysis, cubic NiO and hexagonal Zn-doped cubic NiO nanoparticles were formed, and Fourier transform infrared spectroscopy revealed metal dopants and metal-oxygen stretching, as well as Zn substitution and stabilization. A UV analysis revealed that zinc dopants reduced visible light absorption and bandgap. A decrease in bandgap indicates the importance of zinc incorporation and its interface with NiO. Electron scanning microscopy and transmission electron microscopy confirmed that the nanoparticles exhibited quasi-spherical morphologies and contained Ni, Zn, and O elements. Photocatalytic activity of the synthesized Zn-doped NiO nanoparticles increased with increasing Zn content, achieving a maximum at 8% Zn doping into NiO lattices of 92%. Through XPS analysis, the valencies of Zn, Ni, and O elements are demonstrated, as well as electron movements and bonding between the atoms. The zinc dopants on the metal oxide surface led to charge separation and radical reactions, resulting in enhanced degradation of phorate, salbutamol, and rhoda mine B activities. Hence, Zn-doped NiO nanoparticles are proposed as effective photocatalysts for environmental remediation. The findings are expected to have implications for advancing the field of photocatalysis and addressing challenges related to pollution and energy sustainability.