Hybrid PhotoElectrodes for Selective Reduction of CO2 into Solar Fuels

太阳能驱动化学将二氧化碳还原为C1化合物是可持续生产化学品和燃料的最直接途径。然而，太阳能分子催化剂在化学能转换中的应用尚未成熟，尽管我们已经获得了有效减少二氧化碳的分子催化剂和用于驱动所需高能电子的高性能光电极。如果开发得当，这种分子催化剂和光电极的结合可以为碳利用和无化石能源生产提供可持续的解决方案。然而，阻碍混合光电极应用的两个主要瓶颈是：1。由于与半导体元件的界面会影响催化剂的性能或受到缓慢的界面电荷转移的限制，根据催化剂和光电极的固有特性，光电流通常远低于预期值。2. 二氧化碳转化的选择性常常受到催化剂的局部环境（局部pH值、CO2浓度梯度、周围介质的介电常数、电位梯度）的影响。hype - c1项目将解决这两个瓶颈：我们的总体目标是同时最大化催化速率和产物选择性，通过电子传导矩阵将催化剂集成在光电极上，最终实现高效的光驱动CO2还原为CO，甲醛和甲醇，从而将还原过程从2个电子控制到6个电子。

Solar driven chemistry for CO2 reduction to C1 compounds is the most direct route to sustainable production of chemicals and fuels. However, the application of molecular catalysts for solar to chemical energy conversion has not yet reached maturity even though we have access to molecular catalysts for efficient reduction of CO2 and high performance photoelectrodes for light-driven delivery of the required high energy electrons. If exploited appropriately, the combination of such molecular catalysts and photoelectrodes could offer sustainable solutions for carbon utilization and fossil-free energy generation. However, two major bottlenecks impair the applications of hybrid photoelectrodes: 1. Photocurrents are often far below those expected based on the intrinsic properties of the catalyst and of the photoelectrode because the interfacing with the semiconductor component affects the catalysts properties or is limited by slow interfacial charge transfer. 2. Selectivity in CO2-conversion is often affected by the local environment of the catalyst (local pH values, gradients in CO2 concentration, permittivity of the surrounding medium, potential gradients). The project HYPHE-C1 will address both bottlenecks: Our overarching goal is to concomitantly maximize the catalytic rates and the product selectivity, by integrating the catalyst on a photoelectrode by means of electron conducting matrices to ultimately achieve highly efficient light driven CO2 reduction to CO, formaldehyde and methanol, thus controlling the reduction process from 2 to 6 electrons.