Progressive yield of nickel cobaltite nanocubes for visible light utilization and degrading activities of methyl orange dye pollutant

In this study, pure cobalt oxide (Co₃O₄) as well as nickel cobaltite (NiCo₂O₄) were investigated with their capacity of degradation efficiency for textile dyes like methyl orange (MO) employing visible light irradiation. Two variable concentrations of nickel cobaltite (NiCo₂O₄) with 75:25 and 50:50 wt ratios along with the pure metal oxides were synthesized by thermal decomposition method and analyzed by various sophisticated instruments. Initially, the structural characteristics described the fine crystalline nature of NiCo₂O₄ and also exhibits reduced size than the pure component material (Co₃O₄). Besides, NiCo₂O₄ catalysts represented nano cubic shaped particles, and also their coordinating functional groups were evaluated. Further, the absorption wavelength confirms the two band positions of NiCo₂O₄ which leads to promote visible light absorption, and degrading efficiency of about 47.5% for NiCo₂O₄ (75:25) sample compared with NiCo₂O₄ (50:50) which produced only 26.3% degradation. This higher efficiency of the former was due to high crystallinity and interfacial charge transfer of combined Ni²⁺, Ni³⁺, Co²⁺ and Co³⁺ redox couples. This consecutively produces effective OH radicals that brought the degradation effectively under visible light. The recycling capacity up to 5 repeated cycles has been studied with the NiCo₂O₄ (75:25) and therefore the catalyst can further be used in other dye degradation.