Background Nanoscience and nanotechnology explore the special properties and processes that occur in the nanoscale: the size range conventionally considered as 1-100nm. These fields have emerged as enabling and disruptive, influencing and cutting across all current scientific domains, from medicine to technology, whether fundamental or applied. The central concept underpinning all nanotechnology research is that the properties of matter within the conventionally defined nanoscale are different from those of larger (“bulk”) materials, but also distinct from those of individual atoms. Many significant scientific and technological breakthroughs, from the discovery of graphene, to the development of contrast agents for medical applications, have relied on these unique properties. However, the effective boundaries of nanoscale currently remain poorly defined. To better understand where true novel behaviour starts, and where it ends, this PhD project will focus on experimentally tracking size related transformations of silver, gold and platinum nanoparticles. Computational studies1 of nanoscale transformation of silver nanoparticles, for example, suggest that size-related structural changes to ultra-small (sub-10nm) particles have an influence on their overall physicochemical properties, and can change their reactivity, especially by affecting the nanoparticle surface energy. These studies also showed that at the smaller end of the nanoscale range, nanoparticles transition through several hybrid structures, that have varying stabilities and surface energies; if such structures are indeed stable, and given their high reactivity, they may have an important role in determining overall particle properties. However, to date, they have never been observed in experimental systems. As a result, these theoretical changes in nanostructure are currently not taken into consideration by most researchers, and nanoparticles in the literature are generally viewed as having simple morphologies and smoothly changing reactivity as a function of size. The supervisory team has already showed in preliminary experiments that the most reactive range of silver, gold and platinum nanoparticles differs amongst the three elements and across the nanoscale size range. Through this PhD project, further work will allow us to capture hybrid structures, in space and time, and study them in more detail.
Aim • To establish whether computational predictions agree with physical transformations in cluster morphology and reactivity, beginning with models based on silver and continuing with gold and platinum. • To establish the constraints on reactivity of small nanoparticles and seek rules that apply beyond individual elements in defining the actual boundaries of nanoscale reactivity.
Methodology Four analytical approaches will be used for the experimental work: • Formation of nanoclusters using spark technology and/or magnetron sputtering inert gas aggregation method with size selection capability. • Observations of nucleation and growth of clusters using aberration-corrected Scanning Transmission Electron Microscopy (STEM) and Small Angle X-ray scattering. • In vitro testing of spark generated particles for cell internalization in cell cultures. • The work will be underpinned by computational calculations of particle stability.
Timeline The PhD project is planned for 42 months: M1-3 training needs analysis, literature review, assessment of existing literature on molecular simulations and experimental cluster formation; M3-6 training in analytical methods in Birmingham, especially aberration corrected STEM; M6-12 in depth analytical training in Birmingham; M12-16 experimental design; M16-26 experimental work on cluster development; M26-30 revision of work and refining of experiments - submit as paper; M30-34 design and execute experiments on gold cluster formation; M34-38 design and execute experiments on platinum cluster formation; review of data and consideration of wider implications; submission of further journal paper(s). M38-42 finish write-up.
Requirements Interested applicants should hold a very good BSc degree (2:1 at least) or Masters degrees (desirable) in chemical, physical or environmental sciences or other relevant subjects. Students with an experience of research at undergraduate or Masters level are encouraged to apply. An ability to work both independently and as part of a team and willingness to travel to national and international facilities for research is required. The supervisory team for this studentship includes Professor Éva Valsami-Jones and Dr Ziyou Li. This 3.5 year studentship is funded via a Royal Society Wolfson Fellowship to Professor Valsami-Jones
Please note that only UK and EU citizens are eligible to apply for this studentship. For further enquiries contact Prof. Valsami-Jones ([email protected]). Deadline for applications, 30 August, 2020. To be considered, make sure that you apply through the University of Birmingham online application link. The studentship will start as soon as possible or in October 2020.
1. Martin, P., Zhang, P., Rodger, P.M., Valsami-Jones, E. 2019.Simulations of morphological transformation in silver nanoparticles as a tool for assessing their reactivity and potential toxicity. NanoImpact, 14, 100147.
Insert previous message below for editing?
You haven’t included a message. Providing a specific message means universities will take your enquiry more seriously and helps them provide the information you need. Why not add a message here
The information you submit to University of Birmingham will only be used by them or their data partners to deal with your enquiry, according to their privacy notice. For more information on how we use and store your data, please read our privacy statement.
* required field
Send a copy to me for my own records.
Your enquiry has been emailed successfully
Based on your current searches we recommend the following search filters.