Water is one of the most claimed resources around the world. Due to population increase, the need for clean water is needed. One alternative for wastewater treatment is the use of reactive membranes. Reactive membranes have shown excellent results in pollutant removal and water purification but suffer from the phenomenon known as “fouling”. Fouling occurs due to the accumulation of contaminants on the membrane surface, causing deterioration in its performance. Photocatalysis is a high-performance procedure that uses sunlight for organic molecule degradation. Photocatalytic membranes can be a feasible solution to the fouling phenomenon. Reactive membranes generally have two layers (substrate and active layer) with different functions. In this work, we studied molybdenum disulfide (MoS2) nanosheets as a promising photocatalyst to degrade organic compounds. Our first objective was to synthesize 2D MoS2 nanosheets as they have shown to be the optimal structure for organic molecule degradation. Herein, we studied different parameters such as solvents and sonication amplitude to physically exfoliate the MoS2 nanosheets from their bulk counterpart. Significant differences were found while using water and ethanol as solvents and using 20%, 40%, 60%, 80%, and 100% sonication amplitudes. The UV-Vis spectra showed four maximum peaks characteristic of the MoS2 nanosheets. Few nanosheets were measured by analyzing their morphology with AFM and SEM. The Raman spectroscopy and the XRD results showed that the MoS2 was arranged in its 2H hexagonal phase. Finally, the nanosheets were immobilized over a membrane and tested photodegradation activity using organic dyes under UV-Vis radiation. Our results showed a significant decrease in concentration when cationic dyes were studied. These findings confirm the feasibility of the MoS2 nanosheets, thus we will continue our efforts to perform in-situ decontamination tests.

Synthesis and characterization of 2D molybdenum disulfide nanosheets for organic molecules photodegradation: A water decontamination approach

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.