Facile Synthesis of Cu(OH)2 Rods Supported on Activated Carbon as Efficient Catalyst for Nitrophenol Reduction

Abstract

Aromatic amines constitute pivotal structural motifs in fine chemicals and environmental remediation, necessitating efficient catalysts for nitroarene reduction. Inspired by commercial Pd/C, we devised a facile one-step protocol to in-situ grow needle-like Cu(OH)₂ nanocrystals on activated carbon, affording Cu(OH)₂@AC composites. Systematic XRD, XPS, and TEM characterizations elucidated their phase composition and microstructure. In aqueous NaBH₄-mediated reductions, the optimal Cu(OH)₂@AC-3 delivered activity rivaling commercial Pd/C while outperforming numerous reported non-noble-metal catalysts for the reduction of p-nitrophenol (particularly 4-nitrophenol), and showed the potential to be extended to a broader scope of nitroarene reductions. The catalyst retained robust performance over ten consecutive cycles with negligible copper leaching (0.07%), evidencing strong interfacial metal-support interaction. Kinetic analysis confirmed that the reduction followed pseudo-first-order kinetics, and the apparent rate constant k was determined accordingly. The catalyst integrates facile preparation, earth-abundant raw materials, and low cost, coupled with excellent scalability for large-scale production, holding substantial promise for applications in wastewater remediation and fine chemical synthesis.