权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development and Application of a Flexible Synthesis for Unprotected Colloidal Pt Nanoparticles as a Platform for Systematic Degradation Studies in Electrocatalysis

无保护胶体铂纳米粒子的灵活合成的开发和应用作为电催化系统降解研究的平台

基本信息

批准号：
354106573
负责人：
Professor Dr.-Ing. Bastian Etzold, since 12/2018
金额：
--
依托单位：
Institut für Angewandte und Physikalische Chemie
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/354106573?language=en
关键词：
Development Application Flexible Synthesis Unprotected

项目摘要

The direct use of H2 as an energy carrier is one possible scenario for the switch from nuclear power and fossil fuels to regenerative energy. The fuel cell technology is thereby of significant relevance and the optimization of activity and stability are essential challenges in order to foster their applicability. While the catalytic activity has been investigated quite intensively in the past and active material have been developed, knowledge about relations between the catalyst properties and the stability are still scarce. The primary goal for the proposed project is to establish a preparation platform that enables for systemic investigations of the influence of the most relevant catalyst properties (particle size, loading, and support) on the performance and hence also the catalyst stability. For state-of-the-art fuel cell catalysts (carbon supported Pt nanoparticles) this task can basically be addressed using so-called unprotected Pt nanoparticles (NPs). Such NPs are synthesized as colloids in alkaline ethylene glycol. The application of further preparation steps enables for depositing these particles onto every type of support material. As a result support and particle loading can be controlled independently. However, the application of unprotected NPs is still hindered by the limited control over particle size. Any attempt to achieve particle size control by thermally driven preparation protocols did not give any satisfying results. However, recent investigations have shown that unprotected NPs can also be synthesized using photochemical methods. This so far unexplored potential for controlling the synthesis of unprotected NPs shall be investigated within the proposed project in order to achieve an appropriate particle size control. Such a synthesis protocol will ultimately enable for investigating systematically and independently the influence of the catalytically relevant material properties (particle size, loading, and support).For fuel cells different degradation mechanisms have been identified. The dependence of these mechanisms on the particle size and particle loading of the catalyst has however still not been determined. Therefore, the second part of the project will focus on this topic by using the previously developed synthesis protocol. Model catalysts will be prepared by deposition of the NPs onto TEM grid carbon films. Furthermore, the application of STEM (scanning transmission electron microscopy) as an experimental tool is planned in order to establish an automated, fast method for performing particle size analyses. In contrast to the established methodology of IL-TEM (identical location transmission electron microscopy) the use of STEM enables not merely for local analysis but also for investigating larger areas within a reasonable time frame. This will perspectively allow not merely for qualitative but also quantitative conclusions regarding the relevance of individual degradation mechanisms.

直接使用H2作为能量载体是从核能和化石燃料转向可再生能源的一种可能方案。因此，燃料电池技术具有重要的相关性，并且活性和稳定性的优化是促进其适用性的基本挑战。虽然催化剂的活性在过去已经进行了相当深入的研究，并开发了活性材料，但有关催化剂性能和稳定性之间关系的知识仍然很少。拟议项目的主要目标是建立一个制备平台，以便系统地研究最相关的催化剂性能（粒度、负载和载体）对性能的影响，从而也研究催化剂的稳定性。对于最先进的燃料电池催化剂（碳支撑的Pt纳米颗粒），该任务基本上可以使用所谓的未保护的Pt纳米颗粒（NP）来解决。这种NP在碱性乙二醇中合成为胶体。进一步制备步骤的应用使得能够将这些颗粒沉积到每种类型的载体材料上。因此，可以独立地控制载体和颗粒负载。然而，未保护的纳米颗粒的应用仍然受到对颗粒尺寸的有限控制的阻碍。通过热驱动制备方案实现粒度控制的任何尝试都没有给出任何令人满意的结果。然而，最近的研究表明，未保护的NP也可以使用光化学方法合成。应在拟议项目中研究这一迄今尚未探索的控制未保护纳米颗粒合成的潜力，以实现适当的粒度控制。这样的合成协议将最终能够系统地和独立地调查的影响，催化相关的材料性能（颗粒大小，负载，和支持）。然而，这些机理对催化剂的颗粒尺寸和颗粒负载的依赖性仍然没有确定。因此，该项目的第二部分将通过使用先前开发的合成协议来重点关注这一主题。模型催化剂将通过在TEM网格碳膜上沉积NP来制备。此外，计划将STEM（扫描透射电子显微镜）作为实验工具，以建立一种自动化、快速的粒度分析方法。与已建立的IL-TEM（相同位置透射电子显微镜）方法相比，使用STEM不仅可以进行局部分析，还可以在合理的时间范围内调查更大的区域。这将不仅有助于就个别退化机制的相关性作出定性结论，而且有助于作出定量结论。