Boosting photocatalytic efficiency through Ni–Co co-doped ZnO thin films fabricated by spray pyrolysis

Ni–Co co-doped ZnO thin films were synthesized on glass substrates via the spray pyrolysis technique to investigate the synergistic effect of dual doping on photocatalytic performance. The incorporation of Ni and Co ions effectively modified the structural, morphological, and optical properties of ZnO, as confirmed by XRD, SEM, AFM, EDX, and UV–vis spectroscopy. Photocatalytic tests under sunlight irradiation showed a remarkable enhancement in methylene blue degradation for Ni–Co co-doped ZnO films. In particular, 1.5 % Ni–Co co-doped ZnO achieves a 95 % degradation efficiency after 180 min of sunlight exposure.