Surface Modification of MoS2 Via Fluorine and Bromine Doping for Efficient Catalysis in Oxygen Evolution and Dye Degradation

Abstract

Tailoring highly efficient and robust bifunctional catalysts for enhanced oxygen evolution reaction (OER) as well as organic dye degradation is intriguing but still a triggering concern. Herein, variable concentrations (1 and 3 wt.%) of fluorine (F) with a fixed amount (3%) of bromine (Br) are effectively synthesized in doped molybdenum disulfide (MoS₂) nanosheets by a facile hydrothermal strategy. This research aimed to efficiently degrade Rhodamine B (RhB) dye together with significant OER kinetics. Optical properties, structural morphology, functional group analysis, elemental composition, and crystallinity of synthesized catalysts are investigated by employing cutting-edge techniques. Among all samples, the optimized sample (3% F/Br-MoS₂) exhibited maximum RhB reduction efficacy in a basic medium. Linear sweep voltammetry (LSV), cyclic voltammetry (CV), Tafel plot, and electrochemical impedance spectroscopy (EIS) are conducted to evaluate the electrochemical OER performance of synthesized electrocatalysts. The optimized sample exhibited minimal overpotential, Tafel slope, and charge transfer resistance, indicating the highest OER activity. First-principles calculations of OH⁻ adsorption energies on pristine and F/Br-doped MoS₂ monolayers suggest that F/Br doping may enhance OER activity. This work paves a pathway to the design of unique, cost-effective, and promising materials for synthetic dye removal and high-performance catalysts for water splitting.