Optimization of electrocatalysts for fuel cell applications without alloying: a joint theoretical and experimental study

无合金化燃料电池应用电催化剂的优化：联合理论和实验研究

• 批准号: 355784621
• 负责人: Professor Dr. Aliaksandr Bandarenka
• 金额: --
• 依托单位: Lehrstuhl für Nano- und Quantensensorik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/355784621?language=en
• 关键词: Optimization; electrocatalysts; fuel; cell; applications

Heterogeneous catalysis, including electrocatalysis is among the pillars determining the standards of life nowadays, as catalysts are among the key materials in the modern industry. Fundamental understanding of the mechanisms controlling numerous catalytic properties is therefore of significant importance. One of the most substantial challenges in catalysis today is to develop active and stable materials capable of accelerating key reactions in fuel cells, with a prime focus being set on the oxygen reduction reaction (ORR) taking place at the cathode side of these devices. It has been estimated that increasing the ORR-activity of current Pt electrocatalysts in polymer electrolyte membrane fuel cells (PEMFCs) by ~4-5 times would reduce the necessary amount of this expensive material per vehicle to that averagely used in the catalytic convertors of normal combustion engine cars nowadays (i.e. only to ~4-5g from the current ~20g). Myriads of catalysts were reported recently to address this challenge. One of the main focuses in these efforts was elaboration of alloys of platinum with transition metals. Indeed the activity of Pt can be improved by up to 10 times (Pt-Ni system) compared to pure Pt. However, certain stability issues so far largely limit the use of them. This project uses recent experimental discoveries and fundamental understanding of how one can increase the activity of the surface of pure Pt by at least the factor of 3.5-4.5 without any alloying to design active and more stable electrocatalysts for the oxygen reduction reaction. The key fact in this approach is that it is possible to increase the activity of e.g. Pt by controlling the atom coordination near to the ORR active sites. The aim of this project is to elucidate and implement 3D quasi-open structures with the maximum density of active sites of right coordination, improved stability and local mass transport properties. Successful realization of the proposed project would not only clearly demonstrate the researchers and engineers how to improve the existing materials even without alloying; it would likely establish an entirely new methodology for the development of heterogeneous electrocatalysts based on a combination of theoretical calculations of different levels and experimental approaches which elaborate open 3D-nanostructured materials applicable in the real-world electrocatalysis.

包括电催化在内的多相催化是决定当今生活标准的支柱之一，因为催化剂是现代工业中的关键材料之一。因此，对控制许多催化性能的机制的基本理解是非常重要的。当今催化领域最大的挑战之一是开发能够加速燃料电池中关键反应的活性和稳定材料，主要关注发生在这些设备阴极侧的氧还原反应（ORR）。据估计，将聚合物电解质膜燃料电池（PEMFC）中的当前Pt电催化剂的ORR活性提高约4-5倍将使每辆车所需的这种昂贵材料的量减少到现今在正常燃烧发动机汽车的催化转化器中平均使用的量（即，从当前的约20 g减少到仅约4- 5 g）。最近报道了无数种催化剂来应对这一挑战。这些努力的主要重点之一是铂与过渡金属的合金的制作。事实上，与纯Pt相比，Pt的活性可以提高高达10倍（Pt-Ni系统）。然而，到目前为止，某些稳定性问题在很大程度上限制了它们的使用。该项目利用最近的实验发现和基本理解，即如何在没有任何合金化的情况下将纯Pt表面的活性提高至少3.5-4.5倍，以设计用于氧还原反应的活性和更稳定的电催化剂。这种方法的关键事实是，可以通过控制ORR活性位点附近的原子配位来增加例如Pt的活性。该项目的目的是阐明和实现3D准开放结构的最大密度的活性位点的正确协调，改善稳定性和局部质量传输性能。该项目的成功实现不仅将清楚地向研究人员和工程师展示如何改进现有材料，即使没有合金化;它可能会建立一种全新的方法，用于开发基于不同水平的理论计算和实验方法相结合的非均相电催化剂，这些方法阐述了适用于现实世界电催化的开放式3D纳米结构材料。

项目成果

Tailoring the Oxygen Reduction Activity of Pt Nanoparticles through Surface Defects: A Simple Top-Down Approach

• DOI: 10.1021/acscatal.9b04974
• 发表时间: 2020-03-06
• 期刊: ACS CATALYSIS
• 影响因子: 12.9
• 作者: Fichtner, Johannes;Watzele, Sebastian;Bandarenka, Aliaksandr S.
• 通讯作者: Bandarenka, Aliaksandr S.

In-situ detection of active sites for carbon-based bifunctional oxygen reduction and evolution catalysis

• DOI: 10.1016/j.electacta.2021.138285
• 发表时间: 2021-04
• 期刊: Electrochimica Acta
• 影响因子: 6.6
• 作者: Richard W. Haid;Regina M. Kluge;T. Schmidt;A. Bandarenka

Electrochemical top-down synthesis of C-supported Pt nano-particles with controllable shape and size: Mechanistic insights and application

• DOI: 10.1007/s12274-020-3281-z
• 发表时间: 2020-12
• 期刊: Nano Research
• 影响因子: 9.9
• 作者: Batyr Garlyyev;Sebastian Watzele;J. Fichtner;J. Michalička;A. Schökel;A. Senyshyn;A. Perego;Ding Pan;H. El-Sayed;J. Macák;P. Atanassov;I. Zenyuk;A. Bandarenka