EAGER:CAS-Climate: Novel Non-Precious Metal Catalysts for Oxygen Reduction Reaction

在化学系化学催化项目的支持下，位于派恩布拉夫的阿肯色大学的王道远和位于小石城的阿肯色大学的Anindya Ghosh正在开发新的催化剂，这种催化剂基于地球上丰富的金属，可用于燃料电池。大多数商业上可用的氢氧燃料电池由昂贵的铂（Pt）阳极和阴极组成。因此，为pt基电极制备合适的替代品是一个重要的动机。Wang和Ghosh的合作团队将合成支持在多壁碳纳米管和石墨烯材料上的非贵金属配合物，并评估它们作为质子交换膜燃料电池（pemfc）中氧还原反应（ORR）的催化剂。这项研究预计将影响可再生能源和燃料电池技术，对可持续发展具有重要意义。在理工科中被忽视的少数族裔学生将积极参与研究。该教育项目将包括在阿肯色州周边学校和教育中心开展外展活动，向教师、学生和公众推广绿色化学和可持续能源。本项目旨在开发新的非贵金属ORR反应催化剂，催化剂来源于含有可调酰胺配体的金属配合物。Wang和Ghosh的合作研究团队将设计配体，为金属中心在不寻常的氧化态和有利于氧还原的稳定提供可调的配位环境。酰胺基配合物将被设计成方形平面或包含不同几何形状的弱结合配体，以允许氧与金属中心配合，从而易于还原，同时增强更高的电流密度和更低的过电压。金属配合物将被支撑在碳质纳米材料上。然后将这些支撑系统涂上廉价的生物激发聚合物，如聚多巴胺及其衍生物，并评估其在宽pH范围内增强金属配合物氧化和水解稳定性的潜力，并显着提高ORR活性。将对该三组分体系（金属配合物、碳质支撑物、聚合物涂层）中单个组分的比例和/或类型进行改变，并对实验和电化学结果进行评估。重点将放在了解催化剂活性位点的结构和这些新系统实现的ORR的机制上。研究活动及其与环境可持续性的关系将纳入计划的外联活动。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 from the Chemical Catalysis Program in the Division of Chemistry, Daoyuan Wang of the University of Arkansas at Pine Bluff and Anindya Ghosh of the University of Arkansas at Little Rock are developing new catalysts based on earth-abundant metals for fuel cell applications. Most commercially available hydrogen-oxygen fuel cells consist of expensive platinum (Pt) anodes and cathodes. Thus, a significant motivation for preparing suitable replacements for the Pt-based electrodes exists. The Wang and Ghosh collaborative team will synthesize non-precious metal complexes supported on multi-walled carbon nanotube and graphene materials, and evaluate them as catalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). This research is anticipated to impact renewable energy and fuel cell technology, with important implications for sustainability. Underrepresented minority students in science and engineering will actively participate in the research. The educational program will include outreach activities to surrounding schools and educational centers in Arkansas to promote green chemistry and sustainable energy to teachers, students, and the general public. This project aims to develop new non-precious metal catalysts for the ORR reaction, with the catalysts derived from metal complexes containing tunable amide ligands. The collaborative research teams of Wang and Ghosh will design ligands that will provide tunable coordination environments for the stabilization of the metal centers in unusual oxidation states and favoring oxygen reduction. The amide-based complexes will be designed to be either square planar or to contain weakly bound ligands in different geometries, to allow for oxygen coordination to the metal center for its facile reduction while enhancing higher current density and lower overvoltage. The metal complexes will be supported on carbonaceous nanomaterials. These supported systems will then be coated with inexpensive and bioinspired polymers such as polydopamine and its derivatives, and evaluated for their potential to provide enhanced oxidative and hydrolytic stability to the metal complexes over a wide pH range and to significantly improve ORR activity. Varying the ratios and/or types of the individual components of this three-component system (metal complex, carbonaceous support, polymer coating) will be performed and the results evaluated experimentally and electrochemically. An emphasis will be placed on understanding the structure of the active sites of the catalysts and the mechanisms of the ORR enabled by these new systems. The research activities and their relationship to environmental sustainability will be incorporated into the planned outreach activities.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.