CAREER: Electronic transport and interfacial effects on electrochemical hydrogen evolution reaction for transition metal dichalcogenides

职业：过渡金属二硫属化物电化学析氢反应的电子传输和界面效应

• 批准号: 2240944
• 负责人: Judy Cha
• 金额: $ 58万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2240944&HistoricalAwards=false
• 关键词: CAREER; Electronic; transport; interfacial; effects

Electrochemical catalysis can be used to generate hydrogen from water, thereby offering a sustainable alternative to conventional processes that generate hydrogen from natural gas or petroleum. In recent years, a class of low-cost chemical materials, known as transition metal dichalcogenides (TMDCs), have been identified as promising materials for water-based hydrogen production to power fuel cells and as a raw material for the manufacture of chemicals. Despite their promise, additional scientific understanding and engineering design will be needed to maximize the performance of the dichalcogenide materials to levels rivaling more expensive state-of-the-art platinum-based catalysts. To that end, the project will explore fundamental aspects of the dichalcogenide materials and their effectiveness for hydrogen generation utilizing a unique reactor system. The research will help pave the path to a sustainable energy and chemicals future while also laying ground work for long-term competitiveness of the U.S. in the fuels and chemical manufacturing sectors. The research will be integrated with educational and outreach activities emphasizing participation by under-represented groups. The project seeks answers to the extent that electronic transport properties and interfacial effects (rather than the free energy of hydrogen adsorption) limit the overall rate of the hydrogen evolution reaction (HER) on TMDCs. A single-crystalline flake nanodevice will be employed as a HER micro-reactor, which allows precise control of the density and types of catalytic sites, and accurate measurements of charge transport within the catalyst, as well as the Schottky barrier at the catalyst/current collector interface. Three aims are proposed to study how the TMDC electrical properties, interfacial Schottky barrier, and the hydrogen adsorption free energy change as a function of 1) the phase transition from the semiconducting 2H to the semi-metallic 1T' phase of TMDCs, 2) strain engineering of TMDCs, and 3) different current collectors. The changes in the various properties will be correlated with the measured HER activities using a standard three-electrode cell coupled to the individual TMDC nanodevices in sulfuric acid electrolyte solution. Semiconducting MoS2 and WS2, and semi-metallic MoTe2 and WTe2 nanoflakes will be used for the proposed research, grown by chemical vapor deposition or exfoliated mechanically from bulk crystals grown by chemical vapor transport. Beyond optimization of TMDC materials for HER, the nanodevice platform can be applied to other electro- and photo-catalysts to correlate their catalytic properties to critical parameters such as energetics of catalytic sites, equilibrium electrical properties, interfacial effects, and excited states induced by photons. The project will link the research to education and outreach activities via three outreach programs targeting, respectively, the general public (a weekend Energy symposium at Yale West Campus), under-represented undergraduate students (a monthly seminar series given by minority faculty members), and local high school students (a demonstration HER kit and workbook based on TMDC thin films).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

电化学催化可用于从水中产生氢气，从而为从天然气或石油中产生氢气的传统工艺提供可持续的替代方案。近年来，一类被称为过渡金属二硫属化物（TMDC）的低成本化学材料已被认为是用于水基制氢以驱动燃料电池的有前途的材料以及作为化学品制造的原材料。 尽管前景广阔，但仍需要更多的科学理解和工程设计，以最大限度地提高二硫属化物材料的性能，使其达到与更昂贵的最先进铂基催化剂相媲美的水平。为此，该项目将探索二硫属化物材料的基本方面及其利用独特的反应器系统产生氢气的有效性。该研究将有助于为可持续能源和化学品的未来铺平道路，同时也为美国在燃料和化学品制造领域的长期竞争力奠定基础。 该研究将与强调代表性不足群体参与的教育和外展活动相结合。 该项目寻求电子输运特性和界面效应（而不是氢吸附的自由能）限制TMDC上析氢反应（HER）总体速率的答案。 单晶片状纳米器件将被用作 HER 微反应器，它可以精确控制催化位点的密度和类型，并精确测量催化剂内的电荷传输以及催化剂/电流处的肖特基势垒收集器接口。提出了三个目标来研究 TMDC 的电性能、界面肖特基势垒和氢吸附自由能如何随 1) TMDC 从半导体 2H 相到半金属 1T' 相的相变，2) 应变而变化TMDC 的工程设计，以及 3) 不同的集电器。各种特性的变化将与在硫酸电解质溶液中使用与单个 TMDC 纳米器件耦合的标准三电极电池测量的 HER 活性相关。半导体 MoS2 和 WS2，以及半金属 MoTe2 和 WTe2 纳米片将用于拟议的研究，通过化学气相沉积生长或从化学气相传输生长的块状晶体中机械剥离。 除了针对 HER 优化 TMDC 材料之外，纳米器件平台还可应用于其他电催化剂和光催化剂，将其催化特性与关键参数相关联，例如催化位点的能量、平衡电特性、界面效应和光子诱导的激发态。该项目将通过三个外展计划将研究与教育和外展活动联系起来，分别针对公众（耶鲁西校区的周末能源研讨会）、代表性不足的本科生（由少数族裔教职人员每月举办的系列研讨会）、和当地高中生（基于 TMDC 薄膜的演示 HER 套件和工作簿）。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Role of Heterointerface in Lithium-Induced Phase Transition in T d -WTe 2 Nanoflakes

异质界面在 T d -WTe 2 纳米片中锂诱导相变中的作用

• DOI: 10.1021/acsaelm.3c01329
• 发表时间: 2024-02
• 期刊: ACS Applied Electronic Materials
• 影响因子: 4.7
• 作者: Xu, Shiyu;Wang, Mengjing;Bambrick;Evans;Williams, Natalie L.;Cha, Judy J.
• 通讯作者: Cha, Judy J.

Compact Super Electron-Donor to Monolayer MoS 2

单层 MoS 2 的紧凑型超级电子给体

• DOI: 10.1021/acs.nanolett.2c01167
• 发表时间: 2022-06
• 期刊: Nano Letters
• 影响因子: 10.8
• 作者: Reed;Chen, Yifeng;Yarali, Milad;Charboneau, David J.;Curley, Julia B.;Hynek, David J.;Wang, Mengjing;Williams, Natalie L.;Hazari, Nilay;Quek, Su Ying;et al
• 通讯作者: et al

Efficient electrocatalytic valorization of chlorinated organic water pollutant to ethylene

氯化有机水污染物高效电催化转化为乙烯

• DOI: 10.1038/s41565-022-01277-z
• 发表时间: 2022-12-19
• 期刊: Nature Nanotechnology
• 影响因子: 38.3
• 作者: Chungseok Choi;Xiaoxiong Wang;Soonho Kwon;J. Hart;Conor L. Rooney;Nia J. Harmon;Quynh P Sam;J. Cha;W. Goddard;M. Elimelech;Hailiang Wang
• 通讯作者: Hailiang Wang