Biomass hydrothermal carbonization solution-assisted synthesis of intercalation-expanded core–shell structured molybdenum disulfide for efficient adsorption of Cr (VI) in electroplating wastewater treatment

Cr (VI) is a common heavy metal pollutant in electroplating wastewater. This study introduces the liquid-phase product from the hydrothermal reaction of coffee grounds (CGHCL) into the synthesis process of molybdenum disulfide, assisting in the fabrication of an intercalated, expanded core–shell structured molybdenum disulfide adsorbent (C-MoS2), designed for the adsorption and reduction of Cr (VI) from electroplating wastewater. The addition of CGHCL significantly enhances the adsorption performance of MoS2. Furthermore, C-MoS2 exhibits exceedingly high removal efficiency and excellent regenerative capability for Cr (VI)-containing electroplating wastewater. The core–shell structure effectively minimizes molybdenum leaching to the greatest extent, while the oleophobic interface is unaffected by oily substances in water, and the expanded interlayer structure ensures the long-term stability of C-MoS2 in air (90 days). This study provides a viable pathway for the resource utilization of biomass and the application of molybdenum disulfide-based materials in wastewater treatment.