ABSTRACT Hematite (α‐Fe 2 O 3 ) application as a photocatalyst is limited by the short lifetime of its photogenerated charge carrier. Common strategies to address this issue, including metal or non‐metal doping and nanocomposite engineering, involve complex synthesis routes, high cost, and potential toxicity. The photocatalytic activity of hematite/goethite nanocomposites produced using a simple, one‐pot hydrothermal method is examined in this study. The hematite/goethite composite with an 81/19 content ratio increased the photocatalytic activity (zero‐order k app : 0.0073 min −1 ) toward methylene blue (MB) degradation compared to pure hematite (k app : 0.0050 min −1 ). The photocatalytic performance of the composite was influenced by the hematite to goethite ratio, H 2 O 2 concentration, and solution pH. The reaction using H 2 O 2 up to 30 mM followed the zero‐order reaction kinetics, while higher amounts of H 2 O 2 changed the reaction kinetic to the first‐order due to the Fe 3+ leaching that accelerates the ●OH production through Fe 3+ /Fe 2+ redox cycling with H 2 O 2 . Furthermore, after the reusability test, approximately 1.4 weight% of the leached Fe compared to the initial catalyst was observed as an indication of the gradual release of Fe, which increased the MB degradation rate. This study highlights the potential of hematite/goethite composites as low‐cost, efficient, and eco‐friendly photocatalysts for wastewater treatment.
Basuki et al. (Wed,) studied this question.