A highly efficient CuO/ZrO2/Al2O3 ternary nanocomposite was synthesized using a green and cost-effective electrochemical method. The crystallinity, morphology, elemental composition, surface adsorption (BET), optical, catalytic and biological properties of the nanocomposite was systematically characterized using advanced analytical techniques. XRD analysis confirmed the presence of distinct peaks corresponding to CuO, ZrO2, and Al2O3, indicating the successful formation of a visible-light-active catalyst. SEM images revealed strong interfacial interactions between CuO and ZrO2 integrated within the porous, high-surface-area structure of Al2O3, UV-Visible and DRS analysis determined the band gap energy to be 2.5 eV. The nanocomposite demonstrated excellent photocatalytic efficiency in degrading Indigo Carmine (IC) dye, achieving up to 95  removal. The high surface area of Al2O3 (195 m²/g) facilitated dye adsorption, while the CuO– ZrO2 heterojunction enhanced charge separation: sunlight-excited electrons from p-type CuO were transferred to n-type ZrO2 reducing recombination. Additionally, the nanocomposite exhibited significant antimicrobial activity against various bacterial and fungal strains, outperforming standard references. The novelty of this work lies in the green electrochemical synthesis of a CuO/ZrO₂/Al₂O₃ ternary heterojunction photocatalyst that uniquely combines high surface area, efficient charge separation, and visible-light activity, enabling dual photocatalytic and antimicrobial functionality.
Nagaraju et al. (Thu,) studied this question.