EAPSI: Developing Iridium-based Alloys as Effective Catalysts for Direct Ethanol Fuel Cells

燃料电池能够将不同的化学物质直接转化为电能，比传统的内燃机效率高得多。直接乙醇燃料电池(DEFC)使用乙醇作为燃料来源。然而，DEFC商业化的一个限制因素是一种廉价、高效的乙醇裂解催化剂。Ir合金(两种或两种以上材料的组合)是很有前途的催化剂，因为它们具有高催化活性，而且比传统的燃料电池催化剂铂便宜。在实验上合成和测试所有可能的合金是不现实的。因此，该项目的目的是开发Ir基合金的原子模型，以便预测哪些合金可能是稳定的、良好的催化剂。使用高性能计算机的模拟可以快速、经济地预测潜在的合金，然后可以在实验室进行测试。因此，这项工作将加快新的DEFC催化剂的商业化进程，并将与日本京都大学著名的金属合金建模专家Yutaka Yuge教授合作进行。开发高效的直接乙醇燃料电池(DEFC)催化剂在催化和燃料电池领域具有特别重要的意义。与其他类型的燃料电池相比，DEFC有几个优势，主要是因为它们的原料乙醇具有高能量密度，比氢更安全，比甲醇毒性更小(氢和甲醇都是燃料电池饲料)。为了找到最好的Ir基合金，PI将结合使用密度泛函理论(DFT)和团簇展开(CE)方法。将这两种技术结合起来，将解决DFT方法由于计算能力有限而受到的限制。该项目将在京都大学教授Kutaka Yuge的指导下进行，他在DFT和CE方法的结合方面做了大量研究。东亚和太平洋夏季学院计划下的这个奖项支持一名美国研究生的暑期研究，由NSF和日本科学促进会联合资助。

Fuel cells enable the conversion of different chemicals directly into electrical energy, and are much more efficient than conventional combustion engines. Direct ethanol fuel cells (DEFC) use ethanol as a fuel source. However, a limitation in commercialization of DEFCs is a cheap, efficient catalyst to break apart ethanol. Iridium alloys (a combination of two or more materials) are promising catalysts as they possess high catalytic activity and are cheaper than platinum, the traditional fuel cell catalyst. Synthesizing and testing all possible alloys experimentally is not realistic. The aim of this project is therefore to develop atomic models of Iridium-based alloys in order to predict which alloys may be stable, good catalysts. Simulations using high-performance computers allow fast, economical prediction of potential alloys, which may then be tested in the laboratory. This work thus will speed up commercialization of new DEFC catalysts and will be conducted in collaboration with Professor Koretaka Yuge, a noted expert in modeling metal alloys, at Kyoto University, Japan. Developing efficient catalysts for direct ethanol fuel cells (DEFCs) is of special importance in the catalysis and fuel cell communities. DEFCs have several advantages compared to other types of fuel cells mainly because of their feed, ethanol, which has high energy density, is safer than hydrogen and is less toxic than methanol (both hydrogen and methanol are fuel cell feeds). To find the best Ir-based alloys the PI will use a combination of density functional theory (DFT) and the cluster expansion (CE) method. By using these two techniques simultaneously, the limitation of DFT methods due to finite computation power will be resolved. This project will be conducted at Kyoto University under the mentorship of Professor Koretaka Yuge who has done tremendous research on combining the DFT and CE methods.This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is funded jointly by NSF and the Japan Society for the Promotion of Science.