NiFe₂O₄/Multi-walled carbon nanotubes composite for catalytic reduction of p-Nitrophenol

p-nitrophenol (p-NP) is a toxic and persistent compound found widely in industrial wastewater. Hence, an efficient treatment technology that is benign to the environment is needed. This study aimed to develop a cost-effective and efficient catalyst for the removal of p-nitrophenol (p-NP), a toxic pollutant commonly found in industrial wastewater. A novel nickel ferrite/multi-walled carbon nanotube (NiFe₂O₄/MWCNTs) nanocomposite was synthesized via a hydrothermal route, with MWCNTs functionalized through acidic oxidation. Characterization techniques confirmed the uniform dispersion of NiFe₂O₄ nanoparticles on the MWCNTs surface. Notably, the NiFe₂O₄ nanoparticle nanoparticles were uniformly dispersed on the surface of the MWCNTs, resulting in an enhanced surface area and pore volume. A significant enhancement in catalytic performance was observed for the NiFe₂O₄/MWCNTs composite compared to individual NiFe₂O₄ and MWCNTs, achieving a 97.5 % reduction of p-NP within 12 min. This exceptional efficiency is attributed to the synergistic interaction between NiFe₂O₄ and MWCNTs with an expansive surface area of 194 m²/g, which facilitates enhanced adsorption and electron transfer. Ultimately, the reduction adhered to pseudo-first-order kinetics, with observed rate constants of 0.2908 min⁻¹, 0.2144 min⁻¹, and 0.1636 min⁻¹ for NiFe₂O₄/MWCNTs, MWCNTs, and NiFe₂O₄, respectively. Furthermore, the nanocomposite maintained stable catalytic activity of up to 94 % efficiency until the third cycle in reusability tests. These findings demonstrate the potential of NiFe₂O₄/MWCNTs nanocomposites as highly efficient and reusable catalysts for the remediation of p-NP and other environmental pollutants.