Synthesis of Z-scheme BiOCI/CuFe₂O₄ Composite with Enhanced Visible Light Photodegradation of Palm Oil Mill Effluent

<jats:title>Abstract</jats:title>
<jats:p>The palm oil industry generated thick brownish liquid waste known as POME (palm oil mill effluent). POME is one of the wastes that can seriously threaten the survival of aquatic life if discharged untreated. In this study, efficient photocatalytic degradation of POME by CuFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> decorated on BiOCl (BiOCl/CuFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub>) was reported. The Z-scheme BiOCl/CuFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> composite was successfully fabricated via a precipitation-hydrothermal method. The fourier-transform infrared spectroscopy (FTIR) result clearly displayed the presence of BiOCl and CuFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> in the composite photocatalyst. Compared to pure BiOCl, the composite photocatalyst demonstrated a redshift in the wavelength absorption and great visible light absorbing ability. The photodegradation experiments indicated that the BiOCl/CuFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> demonstrated exceptional POME degradation and decolourization efficiencies of 60% and 68%, respectively after 720 min illumination when compared to the single-phase component photocatalysts. The photocatalytic enhancement of BiOCl/CuFe<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> can be attributed to the efficient charge carrier separation via the Z-scheme heterojunction.</jats:p>