Enzymes have established as a new class of catalysts in the field of modern synthetic chemistry and continue to gain in importance. Directed evolution is currently one of the most promising approaches aiming at enzymes with desired catalytic activities and it's potentially directly correlates with the library size that can be screened. One of the most powerful approaches to overcome these limitations is arguable the recently introduced microfluidic droplet technology; this methodology not only allows to quickly screen millions of clones in a cost effective manner, but is also broadly applicable since fluorometric as well as colorimetric assays can be used. Interestingly, even though numerous publication highlight its potential, an unambiguous evidence of its ability to provide synthetically relevant biocatalysts still needs to be furnished. In addition, access to this technology is currently limited to a few academic research groups and thus, this approach requires further implementation to evolve as an easily manageable lab routine in the near future. This project is designed to unite three competencies: i) the expertise of the Hollfelder Group in regarding micro-engineering and protein engineering in droplets, ii) the empirical knowledge of (bio)chemists at Johnson Matthey in view of economically successful industrial applications of biocatalysts and iii) the strong track record of the experienced researched to successfully solve problems at the biology/chemistry-interface. The objective of the project is to perform a proof-of-principle study by improving a well-known alcohol dehydrogenase for the selective desymmetrization of a meso-diol, thereby giving access to a synthetically sophisticated alcohol. In addition, the final aim is not only to obtain an improved mutant which allows to perform the selected biotransformation efficiently, but also a comparison of varying evolution paths differing in the criteria of hit selection between mutagenesis rounds.

Despite the high thermodynamic stability of CO2, biological systems are capable of both activating the molecule and converting it into a range of organic molecules, all of which under moderate conditions. It is clear that, if we were able to emulate Nature and successfully convert CO2 into useful chemical intermediates without the need for extreme reaction conditions, the benefits would be enormous: One of the major gases responsible for climate change would become an important feedstock for the chemical and pharmaceutical industries! Iron-nickel sulfide membranes formed in the warm, alkaline springs on the Archaean ocean floor are increasingly considered to be the early catalysts for a series of chemical reactions leading to the emergence of life. The anaerobic production of acetate, formaldehyde, amino acids and the nucleic acid bases - the organic precursor molecules of life - are thought to have been catalyzed by small cubane (Fe,Ni)S clusters (for example Fe5NiS8), which are structurally similar to the surfaces of present day sulfide minerals such as greigite (Fe3S4) and mackinawite (FeS).Contemporary confirmation of the importance of sulfide clusters as catalysts is provided by a number of proteins essential to modern anaerobic life forms, such as ferredoxins, hydrogenases, carbon monoxide dehydrogenase (CODH) or acetyl-coenzyme A synthetase (ACS), all of which retain cubane (Fe,Ni)S clusters with a greigite-like local structure, either as electron transfer sites or as active sites to metabolise volatiles such as H2, CO and CO2. In view of the importance of (Fe,Ni)S minerals as catalysts for pre-biotic CO2 conversion, we propose employing a robust combination of state-of-the-art computation and experiment in a grand challenge to design, synthesise, test, characterise, evaluate and produce for scale-up novel iron-nickel sulfide nano-catalysts for the activation and chemical modification of CO2. The design of the (Ni,Fe)S nano-particles is inspired by the active sites in modern biological systems, which are tailored to the complex redox processes in the conversion of CO2 to biomass.The scientific outcome of the Project will be the design and development of a new class of sulphide catalysts, tailored specifically to the reduction and conversion of CO2 into chemical feedstock molecules, followed by the fabrication of an automated pilot device. Specific deliverables include:i. Atomic-level understanding of the effect of size, surface structure and composition on stabilities, the redox properties and catalytic activities of (Fe,Ni)S nano-catalysts;ii. Development of novel synthesis methods of Fe-M-S nano-clusters and -particles with tailored catalytic properties (M = Ni and other promising transition metal dopants);iii. Rapid production and electro-catalytic screening of lead nano-catalysts for the activation/conversion of CO2;iv. Development and application of a new integrated design-synthesis-screening approach to produce effective nano-catalysts for desired reactions;v. Construction of a prototype device capable of catalysing low-temperature reactions of CO2 into products at typical low-voltages, that can be obtained from solar energy; vi. Identification of optimum process for scale-up in Stage 2, from the Economic, Environmental and Societal Impact evaluationThe target at the end-point of Stage 1 is the fabrication of a photo-electrochemical reactor capable of harvesting solar energy to (i) recover CO2 from carbon capture process streams, (ii) combine it with hydrogen, and (iii) catalyse the reaction into product. In Stage 2 of the project, the prototype will be developed into a scaled-up commercially viable device, using optimum catalyst(s) in terms of (i) reactivity/selectivity towards the desired reaction; (ii) economic impact; and (iii) environmental, ethical and societal considerations.

The proposed research is part of a research study on the development of a diesel engine emissions reduction system with enhanced performance by utilisation of hydrogen produced on-board by exhaust gas fuel reforming. The research is motivated by the requirement of diesel engines to meet future emission regulations and by the potential of on-board exhaust gas fuel reforming to provide a way of improving diesel combustion and emissions as well as increasing the efficiency of diesel engine aftertreatment devices.The system targets are to achieve HC, CO and particulate matter (PM) emissions reduction of >90% using a diesel oxidation catalyst (DOC) and a diesel particulate filter (DPF), respectively, and NOx reduction of >70% using lean NOx catalyst technology (HC-SCR or NH3-SCR or NOx trap). The system will have to be cost effective (i.e. use of base metal catalyst or reduced precious metal catalyst content) and should operate without the need of specific engine map development.Specifically, the purpose of the present proposal is to extent the scientific knowledge on PM aftertreatment assisted by reformate addition that will allow successful integration of the DPF and reforming technologies.The study unfolds into two main parts: i) investigation of the use of reformate to promote the soot oxidation and hence improve the DPF regeneration at low exhaust gas temperatures (Brunel University) and ii) investigation of the improvement of DPF regeneration by soot oxidation with NO2 achieved through promotion of the low temperature NO to NO2 conversion rates in a DOC situated upstream of the DPF by addition of small quantities of reformate (University of Birmingham).By extending the understanding of the fundamental processes occurring during NO oxidation and filter regeneration, new catalysts and catalytic systems will be designed and guidelines for the further stages of the research programme towards a full working diesel engine - fuel reformer - aftertreatment system will be developed.

The project aims to produce efficient, inexpensive, visible light-absorbing, robust, high surface area, long-lasting, anion doped, titania photocatalytic monoliths for mediating the reduction of CO2 to methanol and/or methane, using high levels of CO2 and selective catalysts (such as Cu metal deposits) to ensure high efficiencies (> 10%) and the production of easily used fuels. The project will focus particularly on the generation methane and methanol by using nanoparticulate metals, on the CO2 side of the photocatalyst monolith, known to favour their production in the electrochemical reduction of CO2. These reduced forms of carbon fuels are of relevance to the fuel cell and natural gas industries. Demonstrators of the best of the monoliths will be constructed to help promote the technology to those working in the Energy industry, who, at the end of the study, will be encouraged to contribute to the next phase of the work, namely, the subsequent scale-up and advanced prototype development of the monolithic photocatalyst aerogel diode technology. The real novelty in the work is in the separation of the reduced carbon fuel/oxygen evolution events to the separate opposing sides of a robust, inorganic, inexpensive photocatalytic membrane, i.e. the aerogel photodiode / hence, minimising, if not eliminating the various efficiency-lowering recombination reactions. Each section of the proposal has its own unique aspect, including: the preparation of new photocatalyst materials in aerogel form and the utilisation of nanoparticulate metal catalysts. The project will produce significant underpinning science for the development of monolithic photocatalytic diodes and has the potential to offer a step change in efficiency for energy capture from the sun and also eliminate concerns over the greenhouse effect. The results and demonstration of the proposed novel technology will be of particular interest to many working in the Energy field, including academics and industry, especially those associated with fuel cell technology and/or solar energy to chemical fuel conversion.