Synthesis of novel and sustainable molybdenum disulfide (MoS2)-doped biomass-carbon adsorbent with high-performance sodium diclofenac removal

Abstract

Diclofenac sodium (DCF) is widely used and ends up in water bodies, posing a serious environmental threat. Carbon-based materials are effective adsorbents for removing contaminants from polluted waters. In this study, we synthesized monolayer molybdenum disulfide-doped carbon material (MoS2@CM) via a hightemperature process to assess its efficiency as an adsorbent for DCF adsorption from aqueous solution. The characterization data indicated that MoS2 doping significantly affected the physicochemical properties of the MoS2@CM structure. MoS2-nanoparticles enabled the formation of metal–sulfur– oxygen bonds, which boosted the adsorption of DCF molecules. The suitability of MoS2@CM as an adsorbent for DCF removal was investigated. The MoS2@CM exhibited much faster adsorption kinetics, with an adsorption capacity of 424 mg g−1 at 45 °C. Based on indirect evidence from pH effect, zeta potential, kinetic, and isotherm data, as well as literature on MoS2-doped carbons, we hypothesize that the following interactions may contribute to the adsorption of DCF onto MoS2@CM: pore filling, hydrogen bonding, p–p interactions, and possible electrostatic attractions. The adsorbents were subjected to regeneration, and the results indicated that both adsorbents could be reused for at least 5 consecutive cycles, with MoS2@CM exhibiting a higher reusability than @CM. The @CM and MoS2@CM adsorbents showed excellent performance in treating a synthetic effluent, with percentage removals of 78.7% and 80.2% of the total compounds, respectively, highlighting their potential for treating real effluents. This research provides new pathways for the preparation of biomass/metal/heteroatom materials for effective application in the removal of emerging contaminants from aqueous solutions, and beyond.