The transition to clean renewable energy requires cheaper and more efficient means of both harnessing and storing energy. This is limited by the functional properties of the materials used in devices such as solar cells and batteries. To design new materials with better performance, we must understand the structure of the material and how they work in a given application. In particular, the atomic-level structure and chemistry uniquely determine the material attributes and how well they perform. In this project, I will use solid-state nuclear magnetic resonance (NMR) spectroscopy to identify the mechanisms and structure of functional materials. NMR measures the magnetism of atomic nuclei, which is highly sensitive to the local arrangement of atoms, as well as to motion of the atoms over a wide range of timescales, from picoseconds to minutes. Correlation experiments further measure the interaction between the magnetic moments of different nuclei, enabling spatial proximities of different species to be determined. NMR is particularly well-suited to complex, multicomponent, and/or nanoscale materials, which are challenging to study with other techniques. I will focus on two important classes of materials, hybrid perovskites and MXenes. Hybrid perovskites offer the promise of next-generation solar cells with higher efficiency and lower production costs than current silicon-based photovoltaics. However, their commercialisation is held back by their propensity to degrade under environmental conditions, particularly exposure to light. I will study the effects of light illumination on the structure and dynamics of perovskite materials, to understand how they degrade and, therefore, how to protect against degradation. This will require new experiments to measure the NMR spectra of device-relevant thin-film samples on exposure to light. MXenes are a class of layered 2D materials, reminiscent of graphene, that can be used as batteries or gas sensors and separators. The surfaces of the MXene layers are covered in a disordered array of functional groups which are hard to characterise, but which critically determine the functional properties such as the battery capacity and charging rate, or the gas separation selectivity and sensing limits. To optimise the performance of MXenes in these applications, I will investigate how ions and gas molecules fit between the layers and how this is affected by the surface groups. Advanced NMR methodologies will be used to perform these experiments while charging/discharging the material in-situ, and with in-situ introduction of gas molecules. These ambitious experiments will reveal the structural factors that limit the performance of both sets of materials in real-world applications, thereby guiding the design of improved materials via new formulations, processing methods, and treatment strategies. Overall, this will push the materials towards commercialisation. Moreover, the methodological development and expertise can subsequently be applied to other novel materials with new functional challenges.

The key objectives of this proposal focus on investigating different configurations of domain bundles, or hierarchies found in ferroelectrics; as well as their evolution at the micro and nanoscale, under the application of different external stimuli such as heating and electric bias. The data obtained will be contrasted with classical theories in order to get an insight into their formation mechanisms and dynamics. Queen's University Belfast (QUB) has a strong group investigating a wide range of functional materials, especially ferroelectrics and this project seeks to build upon this experience. However, the principal component of this research relies on performing in-situ transmission electron microscopy (TEM) experiments, heating and electrical biasing, which are not available at QUB. The samples for this project are already being characterized at a basic level at QUB using the existing electron microscopy facilities. The intention of this project is to take these samples to advanced electron microscopy centres, specialising in in-situ TEM experiments for the central part of the project. Four experiments in two different international laboratories are being designed as part of this proposal. The intention is for them to be carried out in summer (July-Sept) 2014. The international visits will provide experience and the opportunity to obtain new expertise in a new and exciting technique for studying dynamics of functional materials.

The solid rocks within Earth's interior can flow, analogous to ice in a glacier, given sufficient time and temperature. This flow, or viscous deformation, has a strong influence on a variety of processes over short and long time scales. Over long time scales, the viscous deformation of rocks controls the motion of Earth's tectonic plates. Over short timescales, the viscous deformation of rocks controls the rate at which stresses buildup on overlying, earthquake-generating faults. However, there are major gaps in our understanding of how these rocks deform, which results in significant uncertainties in modeling these large-scale processes on Earth. One of the largest sources of uncertainty is in understanding how grain boundaries, that is the regions between crystals, deform at extreme conditions. This lack of understanding has major implications for predicting processes in Earth. For instance, if grain boundaries are weak relative to the interiors of crystals, then the rates at which stresses build up on large, earthquake-generating faults may increase tenfold. To address this shortcoming, we will carry out experiments at extreme conditions in which we slide two crystals past each other. In some cases, we will add water to the boundary to test if water increases how fast the crystals slide. The data from many experiments will be used to create an equation that describes how fast the crystals slide under a wide range of conditions. To investigate how individual grain boundaries influence the properties of a rock made up of many crystals, these equations will be incorporated into numerical simulations that predict the behavior of an aggregate of crystals. These simulations will be used to understand the importance of grain boundaries in a variety of important large-scale geologic processes.