Structure–performance insights into MoS2 adsorbents for sustainable dye-contaminated water treatment

The release of synthetic dyes into aquatic systems poses major environmental and health risks, demanding effective and sustainable treatment solutions. Here, MoS 2 nanoflowers were hydrothermally synthesized with systematically varied Mo:S precursor ratios (1:1–1:10) and reaction times (4–24 h) to investigate structure–performance relationships in dye adsorption. Comprehensive physicochemical characterization (XRD, FTIR, SEM, TEM, BET, zeta potential, elemental analysis, TGA) demonstrated that sulfur availability and synthesis time jointly govern phase composition, morphology, surface charge and porosity. Among the investigated materials, MoS 2 -(1:5)-4h exhibited the best performance, achieving maximum adsorption capacities of 160.0 mg g -1 for methylene blue and 234.5 mg g -1 for crystal violet, with >95% dye removal within 10 min at 20 mg L -1 and complete removal within 24 h. Kinetic and isotherm modeling, supported by FTIR and Raman spectroscopy, revealed a multi-step adsorption mechanism dominated by electrostatic attraction, complemented by hydrogen bonding and diffusion-controlled processes at higher dye loadings. The optimized material retained >90% removal efficiency over five adsorption-desorption cycles and remained structurally stable after four months of storage under ambient conditions. Importantly, MoS 2 -(1:5)-4h achieved complete removal of single and mixed dyes in real municipal wastewater, with the wastewater matrix buffering pH changes and supporting practical applicability. By combining controlled synthesis, mechanistic analysis and validation in real wastewater matrices, this work provides experimentally grounded structure-performance insights for the design and practical deployment of MoS 2 adsorbents for sustainable water treatment.