Modelling and characterisation of electron beam processed low dimensional nanomaterials

Lead Research Organisation: University of Nottingham
Department Name: Sch of Chemistry

Abstract

Scientific context and collaboration
High resolution transmission electron microscopy HRTEM has become a common tool for studying the structures of low dimensional nanomaterials, such as graphene or carbon nanotubes. Major challenges in advancing the current capabilities of TEM, beyond structural analysis on the atomic-scale, include 1 establishing TEM as the primary tool for the quantitative characterisation of material dynamic transformations; and 2 enabling novel synthetic routes for the controlled modification of low-dimensional materials using the electron beam e-beam as a direct processing tool.
A paradigm shift for HRTEM and STEM is the controlled manipulation and positioning of individual atoms within a nanomaterial, termed "The Atomic Forge". The latest advances in HRTEM are paving the way for the control of materials with atomic precision, a process currently achievable only by scanning tunnelling microscopy STM, but with the inherent advantages of stability at room temperature and accessibility throughout the 3D volume of the material, free of the low temperature surface assembly limitations associated with STM Turning the dream of using the e- beam as the ultimate synthetic tool into a reality requires comprehensive understanding, both theoretically and experimentally, of material properties at the fundamental level, in terms of their dynamic behaviour and interaction under the processing e-beam.
This PhD project will focus on the investigation of materials under e-beam irradiation, combining the insights of computational modelling and imaging with atomic scale resolution, to predict and explain the dynamic behaviour of low dimensional nanomaterials processed in the TEM. It will involve the close, iterative comparison of theoretical predictions Besley, Chemistry with experimental TEM observations Brown, Engineering. The project will take advantage of the extensive expertise, based in the Computational Nanoscience group, in the School of Chemistry, across a wide range of computational techniques, from modelling large scale systems approaching 500k atoms with classical potentials to high-level density functional theory calculations. The dynamic effects of the e-beam on structure transformations will be modelled explicitly using the group's in-house CompuTEM algorithm resulting in multislice image simulations for direct comparison with experimental TEM images with atomic resolution.

Publications

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Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/N50970X/1 01/10/2016 30/09/2021
1939779 Studentship EP/N50970X/1 01/10/2017 23/06/2021 Edward Mortimer
 
Description Erwin Schrodinger Institute Junior Fellowship 
Organisation University of Vienna
Country Austria 
Sector Academic/University 
PI Contribution During the visit I brought an outside perspesctive to the experimental work being undertaken due to my reserach background in both computational and experimental methodology. This helped to guide experiments given the limited time available on their equipment.
Collaborator Contribution The collaborators offered up their world-leading STEM microscope for the duration of the period, allowing for a large amonunt of data to be collected. When combined with their level of expertise and experience, high quality data was obtained.
Impact The images we obtained have begun to help explain the fundamental interactions taking place under electron beam irradiation. The collaboration aims to include theoretical simulations, probing the dynamics accompanying a specific transformation. This information will guide researchers to better experimental practice through understanding what is happening to their sample under the beam.
Start Year 2019
 
Description Poster Presentation - EMAG 2018 in Warick 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact One of the largest conferences in the field of electron microscopy took place in Warwick. I had the opportunity to do a poster presentation during my first year, exhibiting the work I have done and was about to undertake - focusing primarily on methodology. There was a large number of prominent figures in the field with a large level of interest in the work I was doing.
Year(s) Of Engagement Activity 2018