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确定为用于为燃料电池提供动力的水基制氢的有前途的材料，以及作为制造化学品的原材料。 尽管它们有希望，但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的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。 这项研究将与教育和推广活动结合起来，强调代表性不足的群体的参与。 该项目寻求的答案的程度，电子传输特性和界面效应（而不是氢吸附的自由能）限制的整体速率的析氢反应（HER）的TMDC。 单晶片纳米器件将被用作HER微反应器，其允许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/集电器界面处的肖特基势垒。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作为1）TMDC的从半导体2 H到半金属1 T '相的相变、2）TMDC的应变工程和3）不同集流体的函数而变化。各种性质的变化将与使用标准三电极电池测量的HER活性相关，所述标准三电极电池在硫酸电解质溶液中耦合到各个TMDC纳米器件。半导体MoS 2和WS 2以及半金属MoTe 2和WTe 2纳米片将用于拟议的研究，通过化学气相沉积生长或从通过化学气相传输生长的块状晶体机械剥离。 除了用于HER的TMDC材料的优化之外，纳米器件平台还可以应用于其他电催化剂和光催化剂，以将其催化性能与关键参数相关联，例如催化位点的能量学，平衡电性能，界面效应和光子诱导的激发态。该项目将通过三个分别针对普通公众的外展计划将研究与教育和外展活动联系起来（耶鲁西校区的一个周末能源研讨会），代表性不足的本科生（由少数民族教师提供的每月研讨会系列），和当地的高中生（基于TMDC薄膜的HER演示套件和工作手册）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评估被认为值得支持。影响审查标准。

项目成果

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
• 期刊: Nano Letters
• 影响因子: 10.8
• 作者: Reed-Lingenfelter, Serrae N.;Chen, Yifeng;Yarali, Milad;Charboneau, David J.;Curley, Julia B.;Hynek, David J.;Wang, Mengjing;Williams, Natalie L.;Hazari, Nilay;Quek, Su Ying
• 通讯作者: Quek, Su Ying

Efficient electrocatalytic valorization of chlorinated organic water pollutant to ethylene

• 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: Choi, Chungseok;Wang, Xiaoxiong;Wang, Hailiang
• 通讯作者: Wang, Hailiang