The main objective of this proposal is to optimize the enzyme-electrode interface to achieve efficient bioelectrochemical carbon dioxide (CO2) reduction by formate dehydrogenase (FDH). To achieve the overall goal of the proposed project, the specific objectives are: 1) Incorporation of an unnatural amino acid (UAA) to Molybdenum-containing FDH (Mo-FDH) such that the enzyme can be specifically and covalently attached to electrode surfaces with controlled orientation for improved electron transfer (ET) 2) Tailoring the bio-interface between electrodes and FDH H for facile electrocatalysis by direct ET (DET) or mediated ET (MET). This includes the design electrode surface with pyrene moieties/mediator for directing orientation of biocatalysts on electrode surfaces. 3) Bioelectrosynthetic CO2 capture with electrochemical systems exploiting UAA-FDH H. For this, the prepared UAA containing Mo-FDH based biocathodes will be coupled with a hydrogenase bioanode to provide a complete enzymatic biofuel cell (EBFC) producing formate (HCOO− )and simultaneously producing electrical energy from molecular hydrogen (H2) and CO2. <br/>The project will be conducted in 3 work packages associated with research objectives. An UAA will be introduced to FDH H for the first time, yielding an approach for site-specific functionalization of complex metalloenzymes with this project. The proposed technology is highly attractive because it presents a promising solution to tackle global climate issues and energy concerns by providing improved green conversion of CO2 to chemical fuels. <br/>This project will be undertaken within the group of Professor Ross Milton (University of Geneva, Switzerland) and a secondment of two months is planned with Prof. Jason Chin (MRC Laboratory of Molecular Biology, Cambridge, UK) in order to develop skills in UAA incorporation.