Ultrathin thin-film composite membrane integrated with MoS2 conjugated with thiol ligands for isopropanol dehydration by pervaporation

In recent years, transition metal dichalcogenides (TMDs) have garnered much significant attention for their potential in fabricating high-performance membranes and applications in water treatment. In the present study, molybdenum disulfide (MoS2) nanosheets were modified using organic thiols to synthesize amino, hydroxyl, and carboxyl-functionalized MoS2. These modified nanosheets were subsequently integrated into polyamide matrix to develop thin-film nanocomposite (TFN) membranes for dehydration of isopropanol-water mixtures through pervaporation. A comprehensive examination of the impact of incorporating functionalized MoS2 on the physical and chemical properties and separation performance of the resulting TFN membranes was carried out. Embedding MoS2 created a bumpy structure with protuberances on the membrane surface. Amine groups from the modified MoS2 played a crucial role in crosslinking with trimesoyl chloride during interfacial polymerization, contributing to an enhanced crosslinking degree in the membrane. Compared with the pristine membrane, hydroxyl and carboxyl-modified MoS2, the TFN membrane incorporated with amine-modified MoS2 exhibited the highest separation performance with total flux of 1438 g m−2 h−1 and water content in permeate of 99.37 wt% for separating 70 wt% isopropanol aqueous solution. Remarkably, the TFN membrane exhibited a robust performance under high operating temperatures and high feed water concentrations, demonstrating its resilience in challenging conditions. Furthermore, the membrane exhibited stable long-term operational performance, highlighting its potential for pervaporation dehydration applications in the industry. The insights gained from this study contribute to the ongoing development of advanced membrane technologies based on TMDs. [Display omitted] •MoS2 was facilely conjugated using different organic thiols.•Functionalized MoS2 modulated the cross-linking degree and thickness of separation layer.•Amine functionalized MoS2 enhanced the separation efficiency the most.•Modified membrane exhibited a robust performance at different operating conditions.