Materials with 2D nanostructures, e.g. transition metal dichalcogenides (TMDCs) – MoS2, MoSe2, WS2, are highly promising materials for water purification technologies [Nanoscale, 2016, 8, 15115-15131]. Incorporation of these materials into tuneably porous polymer scaffolds, and accompanying large surface area:volume ratios, is expected to drastically improve performance and make these materials viable as a robust, cost-efficient technology for water treatment in the developing world. Recent developments in low-temperature (200oC) TMDC formation at NTHU [Chueh et al., Materials Today, 2023, 69, 97-106] have made this possible and opened opportunities for scalable, high-yield processing which are compatible with polymeric materials and could facilitate the in-situ formation of TMDC directly on the surface of the scaffold. Such “hybrid” materials would be expected to have superior performance across a range of water purification areas; desalination, capacity for pollutant and heavy metal ion removal and (photo-) catalytical water disinfection.
This project aims to develop and explore new materials and approaches for water treatment based on a combination of the large porosities and tuneable morphologies offered by polymeric scaffold materials (membranes) and 2D nanostructured materials (transition metal dichalcogenides), which offer promise for pollutant removal and catalytic activity and generation of reactive oxygen species. Basing the scaffolds on sustainable, low-cost biopolymers with high-yield, scalable functionalisation methods to generate TMDCs directly on the scaffold aligns this project towards development of low-cost solutions suitable for the developing world and addressing persistent challenges with clean water.
This project will involve:
- Fabrication of porous polymer scaffolds from low-cost, sustainable polymers (cellulose and derivatives) with a range of porosities through established methods (non-solvent induced phase separation and vitrification). Characterisation with optical and electron microscopies, gas sorption, calorimetry and thermal gravimetric analysis.
- Further development of surface coatings and chemical modification protocols for incorporation of 2D materials (TMDCs) onto the surface of and embedded within polymeric scaffolds: vapour deposition of oxide layers or embedding oxide particulates within the scaffold and sulfurisation/selenisation through low-temperature plasma treatment. Characterisation of scaffold surface structure and TMDC morphology will be conducted via electron microscopy and porosity will be assessed through further gas sorption measurements.
- Screening and testing materials performance in water purification. Assessment of membrane flux, fouling, biofouling, rejection of heavy metal/toxic metal ions and organic pollutants, (photo-) catalytic generation of reactive oxygen species.
- Exploration of other applications of 2D TMDCs embedded in scaffolds with complex 3D morphologies and large surface areas, for example in energy and sensing applications.