High Entropy Sulfides as Corrosion Resistant Electrocatalysts for the Oxygen Evolution Reaction

高熵硫化物作为析氧反应的耐腐蚀电催化剂

• 批准号: EP/W033348/1
• 负责人: Alex Walton
• 金额: $ 32.18万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FW033348%2F1
• 关键词: Entropy; Sulfides; Corrosion; Resistant; Electrocatalysts

Hydrogen will play a pivotal role as a fuel in a future decarbonised economy. However, for this to be realised, methods must be found to produce hydrogen on a vast scale with no CO2 emissions (>95% of all hydrogen currently produced is from methane, releasing CO2). The most promising route to do this is via water electrolysis (applying a voltage between two electrodes immersed in water to split the water molecules into hydrogen at one electrode and oxygen at the other). The bottleneck in this process is the oxygen evolution reaction (OER) as this is a complicated, multi-step electrochemical reaction. This reaction can be sped up by the appropriate choice of material for the oxygen-evolving electrode. Some materials are better than others at facilitating this reaction, and hence allow the reaction to happen faster with the same energy input - we refer to these materials as electrocatalysts.Efficient electrocatalysts are desperately needed to increase the efficiency of electrolysers and therefore reduce the cost producing of green hydrogen below that of fossil-fuel-derived hydrogen. However, there is an extremely limited range of materials to choose from, as the anode of an electrochemical cell during water splitting is an exceptionally corrosive environment and most materials simply will not survive long enough to be useful.This proposal aims to explore a new class of materials which have very recently shown promise as electrocatalysts for oxygen evolution, known as High Entropy Sulfides (HES). These are materials made of 5 or more metals mixed in roughly equal proportions along with an equivalent amount of sulfur. The elements in a HES share the same crystal lattice and the metals are randomly distributed throughout this lattice - giving them a very high level of disorder, or entropy. This entropy, counterintuitively, confers the HES exceptionally high corrosion resistance, meaning it can possess the required stability to survive the harsh conditions of electrolysis. Furthermore, the disordered state of the material offers us opportunities to tailor the material properties to optimise catalytic activity. By forcing many different atoms of different sizes to share the same crystal lattice, we can place the material under a lot of strain, the amount of which is tuneable by our choice of elements. This strain can in turn have a profound impact on the electronic behaviour of the material and how molecules from the solution interact with the surface - both of which are critical for the electrocatalytic properties of the material.We believe that the corrosion resistance of HES, coupled with the almost limitless ability to tune the material properties mean that HES could be a game-changer for oxygen electrocatalysis. However, before these materials can really be explored and optimised, the fundamental understanding of the electrochemical behaviour of these materials must be improved. The reaction mechanism for the oxygen evolution reaction on HES is completely unknown, as is the exact relationship between lattice strain and material properties.We propose to use a novel thin-film synthesis technique to rapidly synthesise a wide range of high entropy sulfides for testing. We can then develop protocols to robustly test and compare their electrocatalytic activity and stability. Finally, we will use a range of spectroscopic characterisation techniques to learn about the interplay between lattice strain and electronic structure and which of the elements within the HES are participating in the electrocatalytic reaction.By the end of this project, we plan to have produced a step-change in our understanding of HES as electrocatalysts and have a comprehensive set of design principles to design the most active and stable electrocatalyst for the oxygen evolution reaction.

氢将在未来的脱碳经济中发挥关键作用。但是，为了实现这一点，必须发现方法可以在没有二氧化碳排放的情况下以广泛的规模产生氢（>当前生产的所有氢的95％均来自甲烷，释放二氧化碳）。最有希望的途径是通过水电解（在水中浸入两个电极之间的电压，以将水分子分成一个电极，在一个电极和另一个电极上将其分开）。此过程中的瓶颈是氧气进化反应（OER），因为这是一个复杂的多步电化学反应。可以通过适当选择氧气发展电极的材料选择来加速该反应。某些材料在促进这种反应时比其他材料要好，因此使反应以相同的能量输入的速度更快地发生 - 我们将这些材料称为电催化剂。迫切需要有效的电催化剂来提高电解体的效率，从而降低绿色氢的成本，从而在化石燃料衍生的氢氢中产生。但是，有非常有限的材料可供选择，因为在水分裂过程中，电化学细胞的阳极是一种极具腐蚀性的环境，大多数材料根本无法生存足够长的时间以至于无法有用。该提案旨在探索新的类别的材料，这些材料最近显示出作为氧气进化的型电催化剂，众所周知的高熵硫化物（High Entropy Sulfides（Hiss））。这些是由5个或多个金属制成的材料，混合了大致相等的比例以及同等量的硫。 HES中的元素共享相同的晶体晶格，并且金属在整个晶格中随机分布 - 使它们具有很高的无序或熵。违反直觉的熵赋予了HES极高的耐腐蚀性，这意味着它可以具有在电解严峻条件下生存所需的稳定性。此外，材料的混乱状态为我们提供了定制材料特性以优化催化活性的机会。通过迫使许多不同尺寸的不同原子共享相同的晶体晶格，我们可以将材料放在很多应变下，而元素可以通过我们选择的元素来调节材料。这种菌株反过来又对材料的电子行为产生了深远的影响，以及溶液中的分子如何与表面相互作用 - 这对于材料的电催化特性至关重要。我们相信HES的耐腐蚀性，以及几乎无限的材料能力，可以使材料的材料能够对其进行氧化剂的氧化能力进行氧化能力。但是，在真正探索和优化这些材料之前，必须改善对这些材料电化学行为的基本理解。 HES上氧气进化反应的反应机制是完全未知的，晶格应变和材料特性之间的确切关系也是如此。我们建议使用新型的薄膜合成技术快速合成各种高熵硫化物进行测试。然后，我们可以制定协议来鲁棒测试和比较它们的电催化活性和稳定性。最后，我们将使用一系列的光谱表征技术来了解晶格应变和电子结构之间的相互作用，以及HES中的哪些要素参与了电催化反应。为了结束该项目，我们计划在对HES的理解中进行逐步改变，以使HES的理解为电载体和设计原理的全面反应，并设计了一个主动的设计原理。

项目成果

Deposition of a high entropy thin film by aerosol-assisted chemical vapor deposition.

通过气溶胶辅助化学气相沉积沉积高熵薄膜。

• DOI: 10.1039/d3cc03205a
• 发表时间: 2023
• 期刊: Chemical communications (Cambridge, England)
• 作者: Xiao W

High-entropy materials for electrochemical energy storage devices

• DOI: 10.1039/d3ya00319a
• 发表时间: 2023-10-12
• 期刊: ENERGY ADVANCES
• 作者: Qu，Jie;Buckingham，Mark A.;Lewis，David J.
• 通讯作者: Lewis，David J.

Synthetic Strategies toward High Entropy Materials: Atoms-to-Lattices for Maximum Disorder.

• DOI: 10.1021/acs.cgd.3c00712
• 发表时间: 2023-10-04
• 期刊: CRYSTAL GROWTH & DESIGN
• 影响因子: 3.8
• 作者: Buckingham, Mark A.;Skelton, Jonathan M.;Lewis, David J.
• 通讯作者: Lewis, David J.

A Low-Temperature Synthetic Route Toward a High-Entropy 2D Hexernary Transition Metal Dichalcogenide for Hydrogen Evolution Electrocatalysis.

• DOI: 10.1002/advs.202204488
• 发表时间: 2023-05
• 期刊: ADVANCED SCIENCE
• 影响因子: 15.1
• 作者: Qu, Jie;Elgendy, Amr;Cai, Rongsheng;Buckingham, Mark A.;Papaderakis, Athanasios A.;de Latour, Hugo;Hazeldine, Kerry;Whitehead, George F. S.;Alam, Firoz;Smith, Charles T.;Binks, David J.;Walton, Alex;Skelton, Jonathan M.;Dryfe, Robert A. W.;Haigh, Sarah J.;Lewis, David J.
• 通讯作者: Lewis, David J.