SusChEM: Insights into the Surface Chemistry of Water Oxidation on Pure and Modified Hematite Surfaces

提供可持续能源的解决方案，特别是我们对燃料的需求，可能需要光电催化的发展，使我们能够超越仅仅发电。赤铁矿（氧化铁）基材料很有希望利用阳光进行水氧化，这一反应目前限制了光电催化装置的性能，例如从水分解产生氢气或从二氧化碳还原产生碳氢化合物燃料。氧化铁是一种有吸引力的光电极材料，因为它吸收40%的太阳光谱，而且便宜、丰富、无毒、抗腐蚀稳定。氧化铁的能量转换效率也很低。这可以通过用其他材料修饰表面来改善性能来解决。该项目旨在发展对纯赤铁矿和改性赤铁矿表面水氧化的表面化学的基本理解，这有助于新材料和未来太阳能驱动光催化装置的开发。这项工作涉及研究生和本科生以及博士后研究人员，他们在化学、表面科学和纳米技术方面学习和合作，以发现新的催化剂和推进可持续能源生产。研究结果被整合到本科和研究生课程以及本科和K-12教育推广计划中。通过该奖项，化学部门的化学催化项目资助普林斯顿大学的Bruce Koel博士研究赤铁矿（α - fe2o3）基光阳极上水氧化的基本表面化学和过程。必须提高这种反应的效率，以使若干变革性的太阳能燃料生产技术能够用于未来的可持续能源生产。氧化铁因其吸收光谱和丰富度而具有吸引力，但效率很低。一种策略是通过用助催化剂或掺杂进行表面修饰来改善反应动力学和过电位。Koel博士和他的团队在明确定义的纯和修饰的α - fe2o3单晶电极上建立了成分-活性关系，杂原子位于表面和表面下。他们还通过实验鉴定和表征表面结合的物种，以研究水氧化机制的关键方面。测量包括使用在操作技术，其中电极表面在氧化率测量期间被探测。这项工作提供的见解有助于纳米结构催化剂的合理设计及其在能量转换中的应用。这是一个可持续化学，工程和材料（SusChEM）提案。

SusChEM: Insights into the Surface Chemistry of Water Oxidation on Pure and Modified Hematite SurfacesSolutions for supplying sustainable energy, in particular our demand for fuels, will likely require developments in photoelectrocatalysis that enable us to go beyond only electricity generation. Hematite (iron oxide)-based materials are promising for water oxidation using sunlight, a reaction that currently limits performance in photoelectrocatalytic devices for generating hydrogen from water splitting or hydrocarbon fuel from carbon dioxide reduction. Iron oxide is an attractive photoelectrode material because it absorbs 40% of the solar spectrum, and is cheap, abundant, nontoxic, and stable against corrosion. Iron oxide is also very inefficient for energy conversion. This can be addressed by modifying the surface with other materials to improve performance. This project aims to develop a fundamental understanding of the surface chemistry of water oxidation on pure and modified hematite surfaces, which aid the development of new materials and future solar-driven photocatalytic devices. The work involves graduate and undergraduate students and postdoctoral research associates learning and collaborating on cutting-edge approaches in chemistry, surface science, and nanotechnology for discovering new catalysts and advancing sustainable energy production. The research results are integrated into undergraduate and graduate courses and undergraduate and K-12 educational outreach programs. With this award, the Chemical Catalysis Program of the Chemistry Division funds Dr. Bruce Koel of Princeton University to study the fundamental surface chemistry and processes associated with water oxidation on hematite (alpha-Fe2O3)-based photoanodes. The efficiency of this reaction must be increased to enable several transformative solar fuel production technologies to be utilized for future sustainable energy production. Iron oxide is attractive because of its solar absorption spectrum and abundance, but it is very inefficient. One strategy is to improve reaction kinetics and overpotentials by surface modifications with co-catalysts or by doping. Dr. Koel and his group establish composition-activity relationships on well-defined pure and modified single crystal alpha-Fe2O3 electrodes, with heteroatoms localized at the surface and subsurface. They also experimentally identify and characterize surface-bound species in order to investigate key aspects of the water oxidation mechanism. Measurements include using in operando techniques in which the electrode surface is probed during oxidation rate measurements. Insights provided by this work benefit the rational design of nanostructured catalysts and their applications in energy conversion. This is a Sustainable Chemistry, Engineering & Materials (SusChEM) proposal.