Projects Available

The following projects are available for prospective DPhil students:

Deposition of organic an inorganic layers on polymer substrates by roll-to-roll coating in vacuum

Prof. Hazel Assender

The project will make use of our roll-to-roll polymer web coater to deposit under vacuum acrylate or other organic layers on polymer substrates, followed by evaporation or magnetron sputtering deposition of thin film inorganic layers such as metals or oxides. The resulting materials will then be characterized using a suite of methods. Possible applications include optical coatings, gas barrier films (often for electronics applications), or flexible electronics.

Phase separation and self-ordering in thin film polymers

Prof. Hazel Assender

The project will examine phase separation and self-ordering processes and morphological changes in thin film polymers, comparing the processes and kinetics in thin film systems with those in the bulk. The work will consider the effect of substrate interactions as well as processing characteristics on the resulting structures.

High gas barrier layers for encapsulation of flexible electronics

Prof. Hazel Assender High performance transparent gas barrier layers are required for the encapsulation of air-sensitive elements of many flexible device technologies. Recent experiments in our group have demonstrated the important role of nano-scale defects in the barrier layers that contribute to the overall transport of water vapour through the encapsulation. This project will utilize our recent developments in Ca test characterization to better understand the transport of water vapour through layered structures under a range of temperature and humidity environments, exploring both the fundementals of what controls of water vapour transport in polymer and composite layered materials, and the key transport processes, linked with the materials microstructure, in novel composite films generated both within this project and from elsewhere.

In-line patterning in vacuum roll-to-roll processing

Prof. Hazel Assender Vacuum deposition by roll-to-roll processing is attractive for some or all components of flexible functional materials and devices, but methods for in-vacuum deposition of patterned layers (i.e. coating only selected areas), using processes desirable for continuous high through-put processing, are less well developed than those based on ambient processing using solution deposition. This project will explore one or more of various options for in-line patterning based on vacuum deposition, developing the process technique on our semi-industrial scale roll-to-roll procesing equipment and characterising the properties of the layers produced.

Self-ordering in peptide thin films

Prof. Hazel Assender Peptides, typically 8 or 9 amino acid sequences long, can self-organise into helical and fibrillar structures, depending on the particular amino acid sequence. This of interest for a variety of hydrogel technologies for example. The self ordering process is highly dependant on the charge on the amino acid sequences and hence the pH and salt concentration of the solution. Thus, when making thin films, the properties of the surface on which the film is cast and the drying process will also affect the resulting morphology and properties. This project will seek to take a rather fundemental survey of these processes to better understand peptide ordering and hence how hydrogels can be tailed for materials properties both in the bulk and as thin films on a substrate.

Electron ptychographic imaging of polymer and macromolecular ordering

Prof P D Nellist, Prof H E Assender

Electron ptychography is a newly available mode of imaging in the transmission electron microscope that is somewhat related to holography. Recent work in Oxford has shown that it can provide sensitive imaging of low atomic number elements while minimising the number of illumination electrons required. A major challenge associated with electron microscopy of polymers is the damage caused to the sample by the electron beam. The development of electron ptychography creates an opportunity to overcome this challenge and to create a new method for high-resolution imaging of polymers. The project will focus on applying electron ptychography to study local molecular ordering processes in polymer thin films that cannot be studied using conventional X-ray and neutron diffraction methods. The polymer interaction with the substrate will form an important part of the study. The project would suit someone interested in applying state-of-the-art electron microscopy methods to materials that have not traditionally been widely studied using electron microscopy.

Also see a full listing of New projects available within the Department of Materials.

Prospective graduate students can also consider projects available through the CDT in plastic electronics in a partnership between Oxford and Imperial College London. CDT in Plastic Electronics