Construction of nickel foam-supported carbon spheres doped with copper nanoparticles for efficient nitrophenol reduction

Abstract

The efficient removal of 4-nitrophenol (4-NP) from wastewater is critical due to its environmental and health hazards. This study presents the synthesis and evaluation of a novel composite membrane for this purpose. By integrating nickel foam (NiF) with carbon spheres (CS) derived from eco-friendly jackfruit seeds and copper nanoparticles (CuNPs), the catalyst membrane (NiF/CS/Cu) leverages the unique advantages of each component. The NiF provides excellent electrical conductivity and structural support, while the CS enhances stability and dispersion of CuNPs. The NiF/CS/Cu membrane exhibited high stability, efficient electron transfer, and superior catalytic activity. The catalyst achieved an outstanding 98.49 % reduction efficiency in converting 4-NP to 4-aminophenol (4-AP) within just 15 minutes, with a high rate constant of 0.201 min⁻¹. Radical scavenger experiments revealed that the reduction mechanism primarily involves electron transfer, with superoxide and hydroxyl radicals playing significant roles. The NiF/CS/Cu composite demonstrated robust performance across multiple cycles, maintaining 92.18 % efficiency, and showed stable structural integrity, as confirmed by X-ray diffraction and scanning electron microscopy analyses. This study highlights the synergistic effects of combining NiF, CS, and CuNPs, offering a practical and effective solution for 4-NP removal and contributing valuable insights into environmental remediation strategies.