Developing Wide Line Solid State NMR as a Novel Analytical Approach to understand Metals in Catalytic Technology for Fuel Cells

开发宽线固态核磁共振作为一种新颖的分析方法来了解燃料电池催化技术中的金属

• 批准号: EP/G00367X/1
• 负责人: John Hanna
• 金额: $ 18.69万
• 依托单位: University of Warwick
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2008
• 资助国家: 英国
• 起止时间: 2008 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FG00367X%2F1
• 关键词: Developing; Wide; Line; Solid; State

The Stern report stresses that that the drive to more sustainable energy and the introduction of new technologies in this area must be urgently pursued. Fuel cells have a key role to play in the future energy economy. However, one of central components in many fuel cells is the precious metal electrodes which are very expensive, such that their longevity and high expense often limit fuel cell economics. Understanding the structure of the precious metal nanoparticles that make up these catalytic layers is often difficult due to the highly heterogeneous, disordered nature of these materials. This project will develop wide line solid state NMR of precious metal nuclei as a new characterisation tool for such nanoparticles. It will bring together a group with a long track record of developing new materials applications of solid state NMR and an internationally-leading industrial group that are developing fuel cell catalyst technologies. The project attempts to fulfil the philosophy of the Sainsbury Review to get the core academic science base interacting more directly with industry. Traditionally, platinum catalysts have been used exclusively for low temperature fuel cells due to their overall adequate activity and stability for three key reactions of interest. More recently, alloying of platinum with various other metals has shown improvements in both activity and selectivity leading to a diverse range of catalysts for specific reactions. Currently, more advanced research concepts are focussed on nano core-shell materials, where a platinum (or platinum alloy) shell is deposited onto a different core (e.g. palladium) to give both activity (through electronic modification) and cost benefits. Of the metals of interest, platinum is key as this is the basis for most current active formulations. Palladium is of increasing interest as recent reports have indicated that alloying palladium with base metals such as iron can increase activity for some reactions to that of platinum. Also, it has been extensively used as a core for platinum. Rhodium has not been extensively investigated for fuel cell catalysis, but it does show promise as a promoter for platinum for the electro-oxidation of ethanol. In addition, rhodium is the key catalytic metal for a large range of gas-phase reactions, including the CO-NOx reaction in automotive catalysis and the reforming of hydrocarbon fuels to give hydrogen. A characterisation approach that combines traditional analysis techniques (e.g. XRD, TEM, XPS) along with determination of the catalytic activity will be employed. This data will be merged with the new and potentially unique information that will be provided by solid state NMR. A fully multinuclear approach will be employed to examine 1H (to elucidate surface speciation and proton mobility, the latter via relaxation and pulsed field gradient measurements), as well as 13C and 27Al of the support materials. However the clear focus of the work here will be developing NMR of the metals directly. There has already been progress made on 195Pt which has shown that in such heterogeneous systems very broad spectral lines indeed can be encountered such that traditional pulsed approaches are not possible. With the use of field-sweep approaches accurate lineshapes of even very broad lines can be recorded. This project will take this philosophy, develop it further for 195Pt and take on the very much more challenging task of examining 103Rh and 105Pd. The reports of solid state NMR from the latter two nuclei are extremely scarce providing an indication of their difficulty. However by the use of the state of the art NMR equipment available (e.g. field sweep, very high magnetic field) and the construction of a probe optimised for the static observation of these nuclei it is anticipated that significant progress can be made in observing such nuclei. This would provide a new analytical probe of these technologically important materials.

严厉的报告强调，必须紧急追求在这一领域推出新技术的动力。燃料电池在未来的能源经济中起着关键作用。但是，许多燃料电池中的中央组件之一是非常昂贵的贵金属电极，因此它们的寿命和高昂的费用通常会限制燃料电池经济性。由于这些材料的高度异质性，无序性质，了解构成这些催化层的贵金属纳米颗粒的结构通常很难。该项目将开发珍贵金属核的宽线固态NMR，作为此类纳米颗粒的新特征工具。它将汇集一个具有较长良好记录的团体，即开发固态NMR的新材料应用以及正在开发燃料电池催化剂技术的国际领先工业集团。该项目试图实现塞恩斯伯里评论的哲学，以使核心学术科学基础与行业更直接相互作用。传统上，由于铂催化剂的整体活性和稳定性，用于三种关键的感兴趣反应，因此仅用于低温燃料电池。最近，铂与其他各种金属的合金化都显示出在活性和选择性方面的改善，从而导致特定反应的各种催化剂范围。当前，更先进的研究概念集中在纳米核壳材料上，在该材料中，铂（或铂合金）壳被沉积在不同的核心（例如钯）上，以提供活性（通过电子修饰）和成本收益。在感兴趣的金属中，铂是关键，因为这是大多数当前主动配方的基础。由于最近的报道表明，与碱金属（例如铁）合金的钯可以增加对铂的反应的活性，因此钯越来越多。而且，它已被广泛用作铂金的核心。尚未对燃料细胞催化进行广泛研究，但它确实显示出作为铂型乙醇电氧化的启动子的希望。此外，若想符是多种气相反应的关键催化金属，包括汽车催化中的氧化型反应和烃燃料的重构以产生氢。将采用一种结合传统分析技术（例如XRD，TEM，XP）以及确定催化活性的表征方法。这些数据将与固态NMR提供的新的且潜在的独特信息合并。将采用一种完全多核方法来检查1H（阐明表面形成和质子迁移率，后者通过弛豫和脉冲场梯度测量值）以及支撑材料的13C和27AL。但是，这里工作的明确重点是直接开发金属的NMR。在195年代，已经取得了进展，这表明在这种异质系统中，确实可以遇到非常广泛的光谱线，因此无法传统的脉冲方法。通过使用扫描方法，可以记录甚至非常宽的线路的准确线形。该项目将采用这种理念，进一步发展为195pt，并承担检查103RH和105pd的更具挑战性的任务。后两个核的固态NMR的报告极为稀缺，这表明了它们的困难。但是，通过使用可用的最新NMR设备（例如，扫描，非常高的磁场）和对这些核的静态观察进行优化的探针的构建，可以预期可以在观察这种核时取得重大进展。这将为这些重要的材料提供新的分析探测。

项目成果

Multinuclear Solid-State NMR Investigation of Hexaniobate and Hexatantalate Compounds.

• DOI: 10.1021/acs.inorgchem.6b00345
• 发表时间: 2016-06
• 期刊: Inorganic chemistry
• 影响因子: 4.6
• 作者: G. Deblonde;Cristina Coelho-Diogo;A. Chagnes;G. Cote;Mark E. Smith;J. Hanna;D. Iuga;C. Bonhomme

Insight into the Partitioning and Clustering Mechanism of Rare-Earth Cations in Alkali Aluminoborosilicate Glasses

• DOI: 10.1021/acs.chemmater.1c01352
• 发表时间: 2021-04
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Hrishikesh Kamat;Fu Wang;Kristian E. Barnsley;J. Hanna;A. Tyryshkin;A. Goel

Crystal Chemistry of Vanadium-Bearing Ellestadite Waste Forms.

• DOI: 10.1021/acs.inorgchem.8b01160
• 发表时间: 2018-07
• 期刊: Inorganic chemistry
• 影响因子: 4.6
• 作者: Yanan Fang;S. Page;Gregory J Rees;M. Avdeev;J. Hanna;T. White

Natural abundance (25)Mg solid-state NMR of mg oxyanion systems: a combined experimental and computational study.

毫克氧阴离子系统的自然丰度 (25)Mg 固态 NMR：实验和计算相结合的研究。

• DOI: 10.1002/chem.200900346
• 发表时间: 2009
• 期刊: Chemistry (Weinheim an der Bergstrasse, Germany)
• 作者: Cahill LS

Adsorption of HF on gibbsite calcined at various temperatures: A solid-state NMR study of low-level fluorinated systems

不同温度下煅烧的三水铝石上 HF 的吸附：低含量氟化体系的固态核磁共振研究

• DOI: 10.1016/j.jpcs.2021.110355
• 发表时间: 2022
• 期刊: Journal of Physics and Chemistry of Solids
• 影响因子: 4
• 作者: Agbenyegah G