Water-splitting for renewable hydrogen energy sources: a molecular level approach

氢是一种可持续的燃料，开发可再生途径对实现净零排放至关重要用于水分解的光催化装置将光收集、光生电荷分离和催化集成到一个装置中，因此为实现这一最终目标提供了一条非常有前途的途径。然而，关键的不确定性仍然存在于设备功能的动力学以及这些动力学如何依赖于材料和设备设计。例如，对于施加的电压或光激发究竟如何在具有动力学挑战性的多步反应（如水分裂）中驱动催化，存在重大争议解决这些问题形成了本项目背后的主要研究问题。在这个项目中，你将专注于可持续燃料合成的一系列无机催化剂。在ICL，您将使用时间和潜在的分辨紫外-可见和近红外光谱电化学来确定催化剂和光吸收剂中的电荷载流子的光谱指纹，以及它们的种群和反应动力学，在操作条件下测量。这些信息将由伦敦大学学院的operando共振拉曼光谱进行补充，这将为这些带电物质的局部结构和构象提供直接的化学见解。这些结构和动力学分析的结合将使分子设计原理得以建立，从而更深入地了解决定光催化材料和器件性能的因素。反过来，这将进一步发展一项至关重要的低碳技术。

Developing renewable routes to hydrogen, a sustainable fuel, is critical to achieving net-zero emissions.1 Photocatalytic devices for water-splitting integrate light harvesting, photogenerated charge separation, and catalysis into a single device and so offer a highly promising route to this end goal. However, key uncertainties remain over the kinetics underlying device function and how these kinetics depend upon materials and device design. There is, for example, significant controversy over exactly how an applied voltage or photoexcitation drives catalysis in kinetically challenging, multi-step reactions such as water splitting.2,3 Addressing these questions forms the main research question behind this project. In this project you will focus on a range of inorganic catalysts for sustainable fuel synthesis. At ICL you will use time and potential resolved UV-Vis and NIR spectroelectrochemistry to determine the spectral fingerprint of charge carriers in catalysts and photabsorbers, as well as their populations and reaction kinetics, measured under operating conditions. This information will be complemented by operando resonance Raman spectroscopy at UCL, which will give direct chemical insight into the local structure and conformation of these charged species. The combination of these structural and kinetic analyses will enable molecular design principles to be established, allowing greater insight into the factors that determine photocatalytic material and device performance. In turn, this will further the development of a crucial low carbon technology.