Scheme: University Research Fellowship
Organisation: University of Oxford
Dates: Oct 2011-Sep 2014
Summary: The properties of materials are governed by their structure, i.e. the way the atoms are arranged. For example, while both diamond and graphite are forms of carbon, their physical and chemical properties are distinct. Nanomaterials can consist of carbon and include fullerenes, carbon nanotubes, and graphene, and of most other elements as well as their combinations. They exhibit relatively few atoms and therefore their properties are even more influenced by the precise position of individual atoms. The formation and resulting structure of nanomaterials are affected by parameters such as the chemical environment, temperature, gas flow rates during production. If we understand how exactly these parameters influence the structure of nanomaterials as they form we will be able to control the properties of nanomaterials - a challenge that has yet to be solved before the potential of nanomaterials can be efficiently exploited. Therefore, we have developed and patented a tool suitable to operate in harsh environments that allows us to selectively collect chemical information and map the reactor environment in situ. By mapping the synthesis reactor we can correlate growth parameters with the different nanostructures that form. With state-of-the-art characterisation techniques, such as atomic-resolution analytical electron microscopy we can also identify the precise chemical composition these individual nanostructures that formed under certain conditions. With this information at hand we can then tune the growth parameters in order to selectively produce nanomaterials with desired properties that we then use for highly efficient gas sensing applications, energy storage devices such as supercapacitors which are used in start and stop systems for hybrid vehicles, or implant materials. Solving challenge of controlled nanomaterials manufacturing is fundamental importance for the development of novel nanomaterials applications in order to address current and future societal needs.
Dates: Oct 2006-Sep 2011
Summary: Nanostructures such as carbon nanotubes (CNTs) and related 1D inorganic nanostructured materials have generated much interest in recent years due to their one-dimensional nature and their extraordinary properties. For example, such nanomaterials can be exceptionally strong, hard, ductile at high temperatures, wear-resistant, erosion-resistant, corrosion-resistant, and chemically very active. However, the properties of nanomaterials are highly dependent on their atomic structure and the way they are produced. Together with my team, we have achieved control over nanotube morphology (e.g. length, diameter) by using techniques that allow us to produce CNTs with lengths in the millimetre range (typical lengths for CNTs are one order of magnitude lower). Moreover, through the modification of carbon network in-situ, i.e. while the nanostructures grow, we have been able to show that the CNT diameter can also be tailored. Such long CNTs can be used to improve the properties of glass. Therefore, we have developed and produced glass composite materials containing continuous, aligned CNTs. The composites show improved thermal and electrical conductivities compared to glass alone which makes them suitable, for example, as heat sinks for microprocessors.
Over the years, different production methods have been developed to produce carbon nanomaterials and the development of the field brings an urgent need for a systematic nomenclature, because carbon nanostructures can range from structurally well defined molecules (fullerenes) to larger ‘macromolecules’ for which the atomic arrangement can not be precisely defined. Therefore, conventional IUPAC chemical notation is insufficient. Together with colleagues based in France and Australia we have developed a simple approach to a standardised nomenclature based on the morphology which is sufficiently general to conveniently group materials, while remaining specific enough to describe local structural variations.
Scheme: Dorothy Hodgkin Fellowship
Organisation: University of Sussex
Dates: Sep 2003-Sep 2006
Summary: This project summary is not available for publication.