NSF-DFG Chem: Photocatalytic Organic Synthesis By High-Efficiency Planar Semiconductors

该项目是通过“NSF-DFG电合成和电催化牵头机构活动（NSF-DFG EChem）”机会授予的，这是一项涉及美国国家科学基金会和德国研究共同体（DFG）的合作招标。这是耶鲁大学和德国伊尔梅瑙理工大学的研究人员之间的合作项目。利用太阳能进行化学反应为传统的热化学制造工艺提供了一种有吸引力的低碳替代方案，该工艺依赖于化石燃料燃烧产生的能量。 然而，光化学过程的采用一直很缓慢，这是由于在将光有效转化为电化学能并将该能量引导到所需的化学反应中存在根本性挑战。该项目解决了这两个限制，采用高效的光吸收剂与光催化涂层相结合，以促进有机化学品的生产。这项研究工作汇集了领先的研究人员，将实验和理论方法的独特结合应用于光催化化学制造的研究。通过国际外联努力，该项目将包括劳动力发展和教育外联，包括指导科学俱乐部的活动，制定可持续技术课程，并提高公众对可持续化学品生产的认识。联合团队将探索使用高效的光吸收剂来实现有机合成。目前，电荷转移能量学和动力学与表面反应性的关系尚不清楚，这限制了基于电荷转移的合成途径的设计。为了解决这一差距，该团队研究了光催化对二甲苯氧化产生对苯二甲酸的模型反应，该反应由氧化钛涂层的平面磷化铝镓铟半导体驱动。该模型反应将探索操纵位置、自由能和电荷转移电位的能力，以及控制产物分布的设计原则。 在操作中，衰减全反射傅里叶变换红外光谱将用于识别关键的表面物种，结合理论和计算建模将研究测量的能量学和产物选择性，同时提供有关表面反应途径的见解。合作研究的重点包括1）表面化学和空穴转移能量学之间的相关性，2）共同进化以实现产物选择性控制，以及3）气相反应器的实现。 从对二甲苯模型反应的见解应该延伸到技术上重要的有机合成，如氧化脱氢，对映选择性交叉偶联，和carbonylation.This奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

This project was awarded through the “NSF-DFG Lead Agency Activity in Electrosynthesis and Electrocatalysis (NSF-DFG EChem)" opportunity, a collaborative solicitation that involves the National Science Foundation and Deutsche Forschungsgemeinschaft (DFG). This is a collaborative project between researchers at Yale University and Ilmenau University of Technology in Germany. Harnessing solar energy for chemical reactions offers an attractive, low-carbon alternative to traditional thermal chemical manufacturing processes that rely on energy from the combustion of fossil fuels. Adoption of photochemical processes has been slow, however, due to fundamental challenges in the efficient conversion of light into electrochemical energy and directing that energy toward desired chemical reactions. The project addresses both limitations by employing efficient semiconductive photoabsorbers combined with photocatalytic coatings to facilitate the manufacture of organic chemicals. The research effort brings together leading researchers to apply a unique blend of experimental and theoretical methods to the study of photocatalytic chemical manufacturing. Through an international outreach effort, the project will include workforce development and educational outreach, including mentoring science club activities, developing courses in sustainable technologies, and raising public awareness of sustainable chemical production. The joint team will explore the use of efficient semiconductive photoabsorbers to achieve organic synthesis. Presently, the relationship of the charge-transfer energetics and kinetics with surface reactivity is not well understood, which limits the design of synthesis pathways based on photocatalysis. To address this gap, the team investigates a model reaction of photocatalytic para-xylene oxidation to produce terephthalic acid, driven by titanium oxide-coated planar aluminum gallium indium phosphide semiconductors. This model reaction will explore the ability to manipulate the location, free energy, and charge-transfer potentials, as well as the design principles for controlling product distribution. In operando, attenuated total reflection Fourier Transform Infrared Spectroscopy will be used to identify key surface species, which in combination with theory and computational modeling will investigate the measured energetics and product selectivity, while providing insight regarding the surface reaction pathways. The collaborative research thrusts include 1) correlation between the surface chemistry and the hole-transfer energetics, 2) coevolution to achieve product selectivity control, and 3) vapor-phase reactor implementation. Insights from the para-xylene model reaction should extend to technologically important organic synthesis, such as oxidative dehydrogenation, enantioselective cross-coupling, and carbonylation.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.