Integrating ZnO/BiOCl@rGO Derived S-Scheme Photocatalyst: Characterization and Mechanistic Insight for Environmental Remediation

Abstract

With the contemporary phenomenon of excessive industrialization, safeguarding and conserving the environment has ascended to the forefront of humanity’s most critical challenges. This investigation delineates the successful synthesis of a novel S-scheme ternary ZnO/BiOCl@rGO photocatalyst via a straightforward hydrothermal method. It is employed to proficiently degrade the carcinogenic dyes of methylene blue and malachite green in industrial effluents. The synthesized photocatalysts were characterized utilizing advanced analytical methodologies to examine their crystallinity, vibrational modes of bonds, surface morphology, elemental composition, chemical oxidation states, optical absorption characteristics, the recombination dynamics of photogenerated charge carriers, specific surface area, and structural attributes. The absorbance of visible light and the catalytic performance of the ternary ZnO/BiOCl@rGO (5% RBZ) photocatalyst exhibited a substantial enhancement in comparison to both the pure ZnO and the ZnO/BiOCl composite. The degradation efficiency of ZnO/BiOCl@rGO (5% RBZ) (93.73%, k = 0.0318 min⁻¹) was found to be 1.7 times superior to that of ZnO/BiOCl and 4.4 times greater than that of pure ZnO in the degradation of methylene blue after 60 min. In a similar vein, the degradation efficiency of ZnO/BiOCl@rGO (5% RBZ) (99.68%, k = 0.0503 min⁻¹) was 1.9 times more effective than ZnO/BiOCl and 3.8 times higher than pure ZnO in the degradation of malachite green after 60 min. The photocatalytic efficacy of ZnO/BiOCl@rGO (5% RBZ) was augmented due to the superior electron transport properties of the rGO layers, which proficiently facilitate the separation of electron–hole pairs. The findings substantiate that the novel S-scheme ternary ZnO/BiOCl@rGO (5% RBZ) photocatalyst represents a cost-efficient solution for the remediation of contaminated water and has the potential to serve as an exemplary material for the reduction of water pollution.