2D material membranes allow the investigation of processes vital to the existence of life and provide a platform for developing next-generation nanofiltration, purification, and healthcare technologies. Such membranes are formed by compacting flakes of, for example, graphene oxide or molybdenum disulphide (MoS2) into micrometre-thick membranes to create a network of fine capillaries. In addition to being used to control the transportation of water and other liquids [1,2], it is possible to use an electric field applied across the membrane to turn water permeation on and off extremely quickly [2]. Recent results have shown the essential role that structure and chemistry play in determining the behaviour of a particular 2D material for a particular application. For example, the carbon/oxygen ratio in graphene oxide membranes is critical to the transport of water although surprisingly this property and its effect on permeability are not completely understood. Knowledge of the exact mechanism through which an electric field can control permeation is also lacking with in situ experiments needed to allow monitoring of material and chemical changes [2]. Water transport through other 2D material membranes such as those consisting of different phases of MoS2 also requires further understanding to enable their properties to be controlled and engineered.
This project will help resolve these issues using the world-class facilities in the York Surface Science Laboratory, in particular, electron spectroscopy and scanning probe microscopy. Building on earlier studies of 2D material membrane properties [1,2], the PhD student will help provide key insight into fundamental nanofiltration processes that will accelerate the development of smart membrane technologies for artificial biological systems, tissue engineering, energy harvesting, and filtration. Novel instrumentation will be developed to allow in situ studies of membrane behaviour whilst additional avenues for investigation such as nanoparticle interaction with 2D membranes will also be pursued [3].
For further information, please contact Dr. Andrew Pratt (
andrew.pratt@york.ac.uk).
[1] K. G. Zhou et al. Electrically controlled water permeation through graphene oxide membranes, Nature 559, 236 (2018)
[2] Q. Yang et al., Ultrathin graphene-based membrane with precise molecular sieving action and ultrafast solvent permeation, Nature Mater. 16, 1198 (2017)
[3] A. Pratt et al., Enhanced oxidation of nanoparticles through strain-mediated ionic transport, Nature Mater. 13, 26 (2014)
