Controlled growth of novel carbon polymorphs

Graphite and diamond are two allotropes of the same element: carbon. Despite having the same composition, they differ significantly in terms of properties: hardness, visual appearance and conductivity. These properties are controlled by differences in structure. Diamond displays a three-dimensional network in which each atom is attached to four nearest-neighbours in a tetrahedral geometry. In contrast, graphite has a two-dimensional layered structure in which each atom is connected with only three others in aplanar geometry. Usually, these two are considered and used separately in distinct areas. However, some samples of diamond and graphite subjected to extreme conditions, like high pressure or temperature, have been shown to have both graphite- and diamond-like phases, forming so-called nanocomposites. Composite, as the name suggests, is acomposition, usually of two materials, in which one still can differentiate between each component despite being mixed. The distinct areas/volumes occupied by different components are called domains. Nano refers to the scale of the observed domains: they cannot be seen with the naked eye; a specialised microscope (e.g., an electron microscope) is necessary. The main property of (nano)composites is the combination of characteristics of both components, hence potentially making use of the best out of each. As aresult, nanocomposites of graphite and diamond are expected to display conducting or semi-conducting properties and similar, or even improved toughness and hardness. There are various hypothetical ways in which diamond-graphite nanomaterials can be modified. These include the amount of each phase, size and distribution of the domains with the composite and how graphitic and diamond domains are attached. At the moment, there is limited knowledge about any of these. This research project aims to answer the following questions:
- What is the scope of diamond-graphite nanocomposite materials?
- What are their potentially useful static and dynamic material properties?
- How is their structure related to their properties? Can they be predicted based on that?
- How to synthesise them in a controlled manner?
The area of diamond-graphite nanocomposites is still in its infancy; previous work focuses on the analysis of natural samples (e.g., meteorites), minuscule laboratory- produced quantities or theoretical considerations. The thorough computational study, in collaboration with the advanced material synthesis lab, has the potential to develop acontrolled synthesis method. While simulations provide insight and suggest sensible reaction conditions without wasting physical resources, performing the reaction in the lab can verify computational findings and result in physical products. The practical aspect leverages the project and allows its future discoveries to be commercialised. Additionally, AI technologies in simulations can expedite the process, allowing for the exploration of more materials within the same timeframe. This project falls within the EPSRC Advanced Materials Research area. It aims to explore, get insight into and develop novel carbon-based nanomaterials with a unique combination of mechanical and electronic properties, which might be of future use in manufacturing, engineering, electronics or customer goods.
The proposed research is interdepartmental, featuring the Wilson and the Grobert groups (Chemistry and Materials Departments, respectively). As the project evolves, it might involve collaboration with the Deringer and Tew groups (both in Chemistry).