Facile fabrication of CuO-CeO2/rGO nanocomposite for enhanced photocatalytic removal of alizarin red textile dye under UV light

Abstract

In this work, a ternary CuO-CeO₂/rGO nanocomposite was successfully synthesized via a simple chemical precipitation method and evaluated as an efficient photocatalyst for the degradation of Alizarin Red (AR) dye under UV-light irradiation. The novelty of this study lies in the integration of CuO and CeO₂ nanoparticles onto reduced graphene oxide sheets to construct a heterostructured photocatalyst with enhanced surface area and improved charge-separation efficiency. Structural and morphological analyses confirmed the successful formation of the CuO-CeO₂/rGO nanocomposite with an average particle size of approximately 50 nm. BET analysis revealed a high specific surface area of 117.47 m² g⁻¹ and a mesoporous structure, providing abundant active sites for photocatalytic reactions. The photocatalytic investigations demonstrated that the nanocomposite achieved approximately 90% degradation of AR dye within 90 min of UV irradiation under optimized conditions. Scavenger studies revealed that superoxide radicals (•O₂⁻) were the dominant reactive species responsible for dye degradation. Furthermore, the photocatalyst exhibited excellent stability, retaining more than 93% of its initial activity after five consecutive cycles. The enhanced photocatalytic performance was attributed to the synergistic interaction among CuO, CeO₂, and rGO, which promoted efficient charge separation and suppressed electron–hole recombination. These findings demonstrate the potential of the CuO-CeO₂/rGO nanocomposite as a stable and efficient photocatalyst for wastewater remediation applications.