CAS: Revealing the Atomic and Electronic Structures of the Photoelectrode/Catalyst/Water Interfaces and Their Effects on Solar Water Splitting

美国威斯康辛大学麦迪逊分校教授崔景信（音译）和美国芝加哥大学教授朱利亚•加利（音译）得到化学学部化学催化项目的支持，正在研究利用太阳能分解水，产生清洁燃料氢气的半导体电极。这些电极被称为光电极，其整体性能在很大程度上受其表面组成和结构的影响。Choi和Galli采用实验和计算相结合的方法，旨在从微观上理解光电极的表面组成和结构如何影响光电极、催化剂涂层和周围水的界面。然后，他们将研究这些接口结构如何影响设备级性能。这些研究有望产生广泛的科学影响，为有效的太阳能水分解的最佳界面的合理设计提供信息。此外，崔教授和加利教授还将在该项目中，就如何验证理论结构模型和如何以稳健的方式比较理论和实验结果进行授课。这将增强可用的基础设施，以指导其他研究人员使用类似的方法研究太阳能水分解和相关系统。该项目还将在一个高度跨学科的环境中培养研究生，并在使用可再生太阳能的清洁燃料生产领域培养多才多艺的研究人员。该项目将为清洁燃料的可持续生产建立基础科学知识，从而广泛造福社会。美国威斯康辛大学麦迪逊分校教授崔景信（音译）和美国芝加哥大学教授朱利亚•加利（音译）在化学系化学催化项目的支持下，正在研究利用太阳能分解水并产生清洁燃料氢气的光电极。他们研究的总体目标是通过紧密结合的实验和计算研究来阐明光电极表面和界面对其光电化学性质影响的原子细节，并建立界面-光电化学性质关系。Choi和Galli先前使用富v和富bi的BiVO4（010）外延光电极证明，即使在相同的（010）面，表面组成/结构也可以显著影响BiVO4的表面能量学和光电化学性能。利用这些实验和计算上都很好的富v和富bi的BiVO4（010）表面，pi将研究表面组成和结构如何影响BiVO4/析氧催化剂（OEC）、BiVO4/水和BiVO4/OEC/水界面的原子和电子结构。然后，使用不同暴露面的富v和富bi BiVO4形成相同类型的界面，以提取与面类型无关的表面组成的一般效果。该项目将从微观角度理解光电极的表面组成和结构如何影响光电极/OEC/水界面以及设备级性能，而不仅仅是对光电极表面和界面的典型现象学研究和理解。这些研究将解决太阳能燃料领域的关键问题，并有可能极大地实现高效太阳能水分解的最佳界面设计，这将是寻求建立新的清洁能源技术的关键进步。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Chemical Catalysis Program in the Division of Chemistry, Professor Kyoung-Shin Choi of the University of Wisconsin-Madison and Professor Giulia Galli of the University of Chicago are studying semiconductor electrodes that can utilize solar energy to split water and produce hydrogen gas, a clean fuel. These electrodes are called photoelectrodes, and their overall performance is affected considerably by their surface composition and structure. Using combined experimental and computational approaches, Choi and Galli aim to obtain a microscopic understanding of how the surface composition and structure of a photoelectrode affect the interfaces of the photoelectrode, the catalyst coating, and the surrounding water. They will then investigate how these interfacial structures influence the device-level performance. These studies are expected to have broad scientific impact, informing the rational design of optimal interfaces for efficient solar water splitting. In addition, as part of this project, Professors Choi and Galli will make tutorials on how to validate theoretical structural models and on how to compare theoretical and experimental results in a robust manner. This will enhance the infrastructure available for guiding other researchers studying solar water splitting and related systems using similar approaches. This project will also train graduate students in a highly interdisciplinary environment and generate versatile researchers in the field of clean fuel production using renewable solar energy. The project will broadly benefit society by building fundamental scientific knowledge toward the sustainable production of clean fuel.With the support of the Chemical Catalysis program in the Division of Chemistry, Professor Kyoung-Shin Choi of the University of Wisconsin-Madison and Professor Giulia Galli of the University of Chicago are studying photoelectrodes that can utilize solar energy to split water and produce hydrogen gas, a clean fuel. The overall goals of their study are to elucidate the atomic details of the impact that the surface and interface of photoelectrodes have on their photoelectrochemical properties using tightly integrated experimental and computational investigations and to establish interface-photoelectrochemical property relationships. Using V-rich and Bi-rich BiVO4 (010) epitaxial photoelectrodes, Choi and Galli have previously demonstrated that the surface composition/structure can remarkably affect the surface energetics and photoelectrochemical properties of BiVO4 even for the same (010) facet. Using these experimentally and computationally well-understood V-rich and Bi-rich BiVO4 (010) surfaces, the PIs will investigate how the surface composition and structure affect the atomic and electronic structures at the BiVO4/oxygen evolution catalyst (OEC), BiVO4/water, and BiVO4/OEC/water interfaces. Then, the same types of interfaces will be formed using V-rich and Bi-rich BiVO4 with a different exposed facet to extract the general effects of the surface composition that are independent of the facet type. This project will provide a microscopic understanding of how the surface composition and structure of a photoelectrode affect the photoelectrode/OEC/water interface and the device-level performance beyond the typical phenomenological studies and understanding of photoelectrode surfaces and interfaces. These studies will address critical questions in the solar fuel field and have the potential to greatly enable the design of optimal interfaces for efficient solar water splitting, an outcome that would be a key advancement in the quest to build out new clean energy technologies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.