An experimental investigation into malachite green degradation using highly active NiFe₂O₄/Bi₄O₅I₂ photocatalyst under visible light

¹ Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, Jalan Universiti, Bandar Barat, 31900 Kampar, Perak, Malaysia
² School of Chemical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysia
³ College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China

^* Corresponding author: lamsm@utar.edu.my

Abstract

In this study, a highly efficient NiFe₂O₄/Bi₄O₅I₂ (NFO/BOI) photocatalyst has been successfully synthesized through the two-step hydrothermal method. Various characterization techniques, including X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), and Mott-Schottky (M-S) analysis were employed to scrutinize the physical, chemical, optical, and electrical characteristics of the as-synthesized photocatalyst. The photocatalytic performance of NFO/BOI was assessed through the degradation of malachite green (MG). The findings revealed that both the weight percent of NiFe₂O₄ loaded and catalyst loading significantly influenced the degradation efficiency of NFO/BOI on MG. Under 1 hour of visible light irradiation, MG achieved an impressive removal rate of 95.04% using NFO/BOI as the catalyst. Radical trapping experiment confirmed that superoxide anion radical plays a pivotal role in the MG degradation progress. This work introduces a novel direction for designing efficient catalysts for the treatment of water pollution using visible light.