Copper Nanoparticles Decorated Alginate/Cobalt-Doped Cerium Oxide Composite Beads for Catalytic Reduction and Photodegradation of Organic Dyes

Cobalt-doped cerium oxide (Co-CeO₂) was synthesized and wrapped inside alginate (Alg) hydrogel beads (Alg/Co-CeO₂). Further, copper nanoparticles (Cu) were grown on Alg/Co-CeO₂ beads. Cu decorated Alg/Co-CeO₂ composite beads (Cu@Alg/Co-CeO₂) were tested as a catalyst for the solar-assisted photodegradation and NaBH₄-assisted reduction of organic pollutants. Among different dyes, Cu@Alg/Co-CeO₂ was found to be the best catalyst for the photodegradation of acridine orange (ArO) under solar light and efficient in reducing methyl orange (MO) with the aid of NaBH₄. Cu@Alg/Co-CeO₂ decolorized ArO up to 75% in 5 h under solar light, while 97% of MO was reduced in 11 min. The decolorization efficiency of Cu@Alg/Co-CeO₂ was further optimized by varying different parameters. Thus, the designed catalyst provides a promising way for efficient oxidation and reduction of pollutants from industrial effluents.