Microfluidic Assembly of Patchy and Janus Particles

How can we control 3D assemblies of colloidal particles? Development of smart, reusable self-assembling colloids will be a critical aspect of future sustainable materials. Self-assemblies are already attracting interest for applications such as catalysis and photonic crystals, but the potential range of functionality and application is near-limitless; see e.g. Chung and Willmott, “3D assembly of Janus spheres: potentials, dynamics, and experiments”, Adv. Phys.: X 9, 2341759 (2024). Our team has interest and expertise in creating and understanding assemblies based on asymmetric micrometer-scale Janus (or ‘patchy’) particles. We have a funded PhD project which will aim to experimentally study passive assembly in microfluidic devices, but we are also interested in hearing from talented students working in this area on an ongoing basis.

Students will be based in our Dynamic Microfluidics Laboratory, which has access to a microfabrication facility that allows us to design and fabricate prototype microfluidic chips, as well as various types of Janus particle. We have a bespoke optical analysis setup which has been designed to observe interactions between small numbers of particles as they occur. The lab also features e.g. high speed cameras, image analysis tools, environmental control, and tensiometry. This project will be based on experimental work, with strong quantitative analysis of results, with the potential to focus further on either theoretical descriptions or technological developments. There is scope for a student to define their own specific areas of interest.

We are a friendly, diverse group and any student will have opportunities for international travel, and we anticipate high-impact research outputs. We are looking for students with a strong Honours or Masters degree in physics, chemistry, engineering, or a related field. Experience with one or more of experimental physical chemistry, microfabrication, experimental fluid dynamics, or optics and image analysis would be beneficial.

The project is funded by the MacDiarmid Institute, one of New Zealand’s Centres of Research Excellence, which provides access to excellent academic and practical training, and to a comprehensive range of tools and expertise throughout New Zealand. The student will benefit from the MacDiarmid Institute’s thriving postgraduate community which delivers various opportunities for personal development. For example, the CRISP programme offers vocational training to enable a smooth transition into an exciting career beyond the PhD.