Advancing physical, dielectric, and solar photocatalytic efficiency with novel Ni0.95Cu0.03M0.02O (M = Co, Mo) semiconductors.

Cu/Mo codoped NiO semiconductors exhibited a visible light efficient photo-removal performance for diclofenac sodium and methylene blue waste. A simple and low-cost methodology was used to synthesize NiO, Ni0.95Cu0.03Co0.02O, and Ni0.95Cu0.03Mo0.02O nanocatalysts. The crystal structure verified the formation of a cubic NiO single phase. The scanning electron microscopy (SEM) micrographs of all samples have shown a homogenous spherical particle distribution. The harvesting of visible light from NiO semiconductors was significantly enhanced after the addition of Cu/Co and Cu/Mo ions. The X-ray photoelectron spectra confirmed that Cu dopant has a +2-oxidation state while Mo dopant has +3 and +4 as mixed oxidation states. Ni0.95Cu0.03Co0.02O and Ni0.95Cu0.03Mo0.02O have shown high dielectric constant values at low frequencies. For purification of wastewater, the visible light photocatalytic efficiencies of Cu/Mo codoped NiO catalyst for the removal of 20 mg/L methylene blue (MB) and 20 mg/L diclofenac sodium (DS) were 98 and 95% after 50 min, respectively. The MB and DS molecules were converted to CO2 and H2O as confirmed by total organic carbon and chemical oxygen demand analyses. Besides, this nanocatalyst showed a high reusability for MB and DS pollutants until four cycles. [ABSTRACT FROM AUTHOR]