Supported heterogeneous catalysts comprising nano-sized metals/metal oxides such as Cr, Ni, Co, Au, Pd, Pt and Ag dispersed on an oxide support (i.e. SiO2/Al2O3), play a central role in an industry estimated to be worth ca. 1500 billion $US/annum. They are the principle protagonists in the conversion of fractions from natural oil and gas to produce, via core catalytic processes (i.e. polymerisation, isomerisation, reduction and oxidation), a wide variety of chemicals for everyday use. A combination of dwindling supply and increasing demand on these feedstocks means it is vital that catalysts and catalytic processes operate as efficiently as possible. Optimal efficiency is normally achieved by rationalisation of structure with function and forms the basis for much catalysis research. However the characterisation performed is often incomplete and rarely performed under reaction conditions leading to contrasting conclusions as to what makes a catalyst active. This project will develop more robust structure-activity relationships by correlating how parameters that influence catalyst performance i.e. nanoparticle size, shape, redox functionality and metal-support interactions, affect and evolve in core catalytic processes of hydrogenation and oxidation. The project adopts a novel approach drawing on skills in catalyst preparation and in situ catalyst characterisation to prepare size-controlled monometallic nanoparticles, deposited on a flat oxide supports and to characterise them in operando using simultaneous time-resolved grazing incidence X-ray scattering (GIXRS) techniques. In particular small angle/wide angle grazing incidence scattering methods (GISAXS/GIWAXS) will be used although attempts will also be made to extract pair distribution function ((GI)PDF) from the data to enable a more complete characterisation of the catalyst. Such a thorough characterisation has never been previously employed and will be used to determine the salient characteristics of catalytic nanoparticles in both two-phase (hydrogenation) and three-phase (oxidation) catalytic systems. It is expected that these measurements will prove invaluable for understanding what makes a supported nanoparticle tick and an important basis for future catalyst optimisation and design.

Iron sulfides are widespread in the environment, where they regulate and control the global geochemical iron and sulfur cycles. However, despite their application as indicators for seawater anoxia and recorders of early-life isotopic and paleomagnetic data, iron sulfide minerals are still largely unexplored compared to, for example, iron oxide minerals or the silicates or carbonates. Numerous iron sulfide phases are known, but many are highly unstable or only partially stable for a short time in the environment. Even the least reactive iron sulfide, pyrite, is no longer stable once exposed to air at the Earth's surface. Its dissolution leads to the problem of acid mine drainage, where sulfuric acid and any trapped toxic metals are released with devastating effects on the environment near the mine. However, iron sulfides also have beneficial effects on the environment, as they easily incorporate metals within their structure, and thus could be sinks for toxic metals or radioactive elements. An intriguing aspect of iron sulfides is the crucial role they may have played in the Origin of Life. Thin layers of iron-nickel sulfide are believed to have formed in the warm, alkaline springs on the bottom of the oceans on Early Earth. They are increasingly considered to have been the early catalysts for a series of chemical reactions leading to the emergence of life. The oxygen-free production of various organic compounds, including amino acids and nucleic acid bases - the building blocks of DNA - is thought to have been catalyzed by small iron-nickel-sulfur clusters, which are structurally similar to the highly reactive present day iron sulfide minerals greigite and mackinawite, yet we know little about how they form. In view of the likely role of such reactive minerals in the conversion of pre-biotic CO2 on Early Earth, we may well be able to harness iron sulfides as present-day catalysts for the same process, thereby potentially aiding the slowing down of climate change by converting the CO2 we produce into useful chemicals. In today's world, the importance of such iron-nickel-sulfide clusters as catalysts has been confirmed, as several life-essential iron-sulfur proteins help transform volatiles such as H2, CO and CO2 into other useful and less harmful chemicals. In all of the above examples, it is important to understand that the reactions that lead to the formation of all these minerals which are necessary for any of the geologically stable minerals to exist (i.e., pyrite) all rely on our understanding of the nucleation and growth of unstable precursors or of the reaction transforming one phase to another. Furthermore, the structure and reactivity of each of these phase determines its role and potential application in the environment. A few research groups in the UK and abroad have carried out high quality investigations of the properties of a number of iron sulfide minerals, but it is particularly difficult to investigate events early on in the nucleation process, even though they set the scene for all subsequent transformations. In this project we propose to employ a robust combination of state-of-the-art computation and experiment to unravel the nucleation of iron sulfide mineral phases. We aim to follow the reactions from the emergence of the first building block in solution, through agglomeration into larger clusters, their aggregation into nano-particles and the eventual transformation into the final crystal. We anticipate that this project, investigating short-lived processes which are only now accessible to study through the development of high temporal and spatial resolution in-situ characterization techniques and High Performance Computing platforms, will lead to in-depth step-by-step quantitative insight into the iron sulfide formation pathways and enhance our fundamental understanding of how a mineral nucleates in solution.

Iron sulfides are widespread in the environment, where they regulate and control the global geochemical iron and sulfur cycles. However, despite their application as indicators for seawater anoxia and recorders of early-life isotopic and paleomagnetic data, iron sulfide minerals are still largely unexplored compared to, for example, iron oxide minerals or the silicates or carbonates. Numerous iron sulfide phases are known, but many are highly unstable or only partially stable for a short time in the environment. Even the least reactive iron sulfide, pyrite, is no longer stable once exposed to air at the Earth's surface. Its dissolution leads to the problem of acid mine drainage, where sulfuric acid and any trapped toxic metals are released with devastating effects on the environment near the mine. However, iron sulfides also have beneficial effects on the environment, as they easily incorporate metals within their structure, and thus could be sinks for toxic metals or radioactive elements. An intriguing aspect of iron sulfides is the crucial role they may have played in the Origin of Life. Thin layers of iron-nickel sulfide are believed to have formed in the warm, alkaline springs on the bottom of the oceans on Early Earth. They are increasingly considered to have been the early catalysts for a series of chemical reactions leading to the emergence of life. The oxygen-free production of various organic compounds, including amino acids and nucleic acid bases - the building blocks of DNA - is thought to have been catalyzed by small iron-nickel-sulfur clusters, which are structurally similar to the highly reactive present day iron sulfide minerals greigite and mackinawite, yet we know little about how they form. In view of the likely role of such reactive minerals in the conversion of pre-biotic CO2 on Early Earth, we may well be able to harness iron sulfides as present-day catalysts for the same process, thereby potentially aiding the slowing down of climate change by converting the CO2 we produce into useful chemicals. In today's world, the importance of such iron-nickel-sulfide clusters as catalysts has been confirmed, as several life-essential iron-sulfur proteins help transform volatiles such as H2, CO and CO2 into other useful and less harmful chemicals. In all of the above examples, it is important to understand that the reactions that lead to the formation of all these minerals which are necessary for any of the geologically stable minerals to exist (i.e., pyrite) all rely on our understanding of the nucleation and growth of unstable precursors or of the reaction transforming one phase to another. Furthermore, the structure and reactivity of each of these phase determines its role and potential application in the environment. A few research groups in the UK and abroad have carried out high quality investigations of the properties of a number of iron sulfide minerals, but it is particularly difficult to investigate events early on in the nucleation process, even though they set the scene for all subsequent transformations. In this project we propose to employ a robust combination of state-of-the-art computation and experiment to unravel the nucleation of iron sulfide mineral phases. We aim to follow the reactions from the emergence of the first building block in solution, through agglomeration into larger clusters, their aggregation into nano-particles and the eventual transformation into the final crystal. We anticipate that this project, investigating short-lived processes which are only now accessible to study through the development of high temporal and spatial resolution in-situ characterization techniques and High Performance Computing platforms, will lead to in-depth step-by-step quantitative insight into the iron sulfide formation pathways and enhance our fundamental understanding of how a mineral nucleates in solution.

Our proposal concerns the development of a world-leading instrument that will characterise more effectively and efficiently than ever before the intense highly collimated X-ray beams produced at Synchrotron Radiation (SR) facilities. The device will combine high-speed performance with extremely sensitive beam position measurement and beam imaging capabilities. For the first time, one instrument will provide a comprehensive set of X-ray beam characteristics: focal size, position, intensity distribution and energy (wavelength). Uniquely for the X-ray region, these measurements can be performed during an experiment: it will be an in situ - but virtually transparent - device, the product of state-of-the-art detector and signal processing technology. The high temporal resolution of the proposed device will enable the fast detection of beam defocus, vibration, shift and intensity fluctuations. Crucially this capability will be augmented by the possibility of feedback of the output signals into the surrounding optical infrastructure to facilitate correction of any beam motion or indeed accurate tracking across a target to perform a two-dimensional scan.In brief, our world-class system will exhibit several innovative features that will significantly improve the accuracy, reliability and scope of data acquired using micrometer-sized X-ray beams. Looking at the wider community of scientists using synchrotron radiation, it should be stressed that the underlying technology of this cutting-edge device is transferable. It will benefit all scientific experiments conducted at all SR facilities, irrespective of their methodology or wavelength range utilised. For example, in imaging experiments, it will lead to sharper images: any blurring and anomalies due to uneven illumination can be removed. In all experiments, energy shifts in the beam impinging on the sample due to angular drift of the beam entering the monochromator may be eliminated. In X-ray diffraction and scattering, intensities may be recorded on an absolute scale doing away with the ubiquitous scale factor and corrections between successive individual measurements taken with varying beam intensities. Experiments in the domain of microscopic imaging and spectroscopy that require the maintenance of a steady incident flux of a highly collimated beam of a microscopic target area provide a challenge for which the new technology is particularly suitable, especially if, as is often the case, a wavelength scan is also required. As examples of nascent fields that would benefit, we cite the study of biological species using fluorescence tomography and microspectrometry.The topicality of the proposed project and general level of interest in the area is indicated by the exponential increase in published research on X-ray beam position monitoring in recent years. Our approach is original and superior to existing solutions, extending the performance envelope of existing in situ beam monitors that monitor beam position alone. Our multidisciplinary research team has already demonstrated the potential of the technology in two successful proof-of-concept experiments [1-3; part 1]. Furthermore, we have dedicated academic and industrial partners on board who are committed to helping us to develop and enable take up of this novel technology.

The thermal boundary layers of a convecting system control many aspects of its style of convection and thermo-chemical history. For the silicate Earth these boundary layers are the lithosphere, whose low temperature and high rigidity induces slab-style downwellings, and the D'' region on the mantle side of the core-mantle-boundary (CMB). The D'' region is the source of plume-style convection and regulates heat exchange from the core to the silicate Earth. The lower thermal boundary is made more complex by the existance of a phase transition in the most common mineral in the lower mantle (magnesium-silicate perovskite) which changes the properties of the D'' region at the CMB. Unfortunately, most of these properties cannot be measured at the extreme pressures (120 GPa) of stabilisation of the post-perovskite phase. The best chance of constraining them is through a combination of measurements on low-pressure analogue materials (which have the same crystal structure but a different chemical composition) and ab initio simulations of both the analogue and natural systems. We have recently developed a set of ABF3 analogues whose properties are much more similar to MgSiO3 than are those of the CaBO3 analogues currently in use. We propose, therefore, to use these improved fluoride analogues to determine the properties of post-perovskite which control the dynamics of D'' (phase diagram, pressure-temperature-volume relations, viscosity, slip systems and thermal diffusivity). These measurements will allow models to be developed which accurately predict the behaviour of the lower thermal boundary layer of the mantle. This will place coinstraints on (1) the heat budget, dynamo power and start of crystallisation of the inner core, (2)the vigour of plumes, (3) the ratio of underside heating to internal heating in the mantle and, (4) the radioactive element budget of the silicate Earth.