Interface Engineering for Solar Fuels

化石燃料的使用和由此产生的二氧化碳排放正在加剧全球气候变化。氢的替代使用可以减少二氧化碳排放，改善城市地区的空气质量，因为燃烧氢气会产生无害的水。为了实现这一潜力，我们需要找到生产氢燃料的清洁方法。利用太阳能、风能或水力发电等可再生能源发电的电解槽，可以清洁地将水分解为氢(和氧)。以一种更直接的方式，还可以使用集成在光电化学(PEC)电池的光电极中的太阳光和半导体吸收层来干净地分解水。由于光生电荷寿命较短和半导体表面在电解液界面裂解水的催化性能较差，PEC太阳能裂水受到限制。这项研究旨在开发新的方法来设计半导体和电解液之间的界面，以优化半导体的性能并实现高效的太阳能器件。我们将开发制造方法来调整这些接口，并提高它们的PEC最终性能。光电极将被制备成定向的，并具有暴露的活性晶面，或在其表面上额外的层以与水电解质相协调。将采用一种系统的方法，包括新的合成、先进的电化学表征和太阳能分水性能测试，以确定形成光电极的最佳条件和使其具有更好性能的特性。最后，将最好的光电极集成到串联电池中，以实现更高效的太阳能分水。制备具有工程界面的半导体将对(光)电化学、光催化、光伏及其能源应用的研究产生相当大的影响。这将确保在为今世后代提供更可持续的清洁能源组合方面取得重要进展。

The use of fossil fuels and resulting CO2 emissions are exacerbating global climate change. The alternative use of hydrogen could cut CO2 emissions and improve air quality of urban areas, since burning hydrogen generates harmless water. To realise this potential we need to find clean ways to produce hydrogen fuel. Water splitting into hydrogen (and oxygen) can be achieved cleanly with electrolysers running on electricity from renewable sources such as solar, wind or hydropower. In a more direct manner, water can also be cleanly split using sunlight and semiconductor absorbing layers integrated in photoelectrodes of photoelectrochemical (PEC) cells. PEC solar water splitting is limited by both poor lifetime of photo-induced charges and poor catalytic properties of semiconductor surfaces to split water at the electrolyte interface.This fellowship aims to develop novel approaches to engineer the interface between semiconductors and electrolytes, in order to optimise the performance of the semiconductors and achieve efficient solar energy devices. We will develop fabrication methods to tune those interfaces and boost their PEC final performance. Photoelectrodes will be prepared oriented and with exposed active crystal facets, or with extra layers on their surface to mediate with aqueous electrolytes. A systematic approach involving novel syntheses, advanced electrochemical characterisation and solar water splitting performance tests will be carried out to establish the optimal conditions for the formation of photoelectrodes and the characteristics which make them better performing. Finally, best photoelectrodes will be integrated in tandem cells for more efficient solar water splitting.Preparing semiconductors with engineered interface will have a considerable impact on the research of (photo)electrochemistry, photocatalysis, photovoltaics and on their energy application. This will ensure important advances towards a more sustainable energy mix of clean energy for current and future generations.