Collaborative Research: EAGER: Insights into the Hydrogen Evolution Reaction of Transition Metal Dichalcogenide Nanocrystals by In-situ Electron Paramagnetic Resonance Spectroscopy

合作研究：EAGER：通过原位电子顺磁共振波谱洞察过渡金属二硫族化物纳米晶体的析氢反应

• 批准号: 2302783
• 负责人: Ashwin Ramasubramaniam
• 金额: $ 12.5万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2302783&HistoricalAwards=false
• 关键词: Collaborative; Research; EAGER; Insights; into

The large-scale deployment of hydrogen (H2) as a clean-energy fuel and chemical precursor will require replacing expensive platinum-group metals that catalyze the electrochemical splitting of water via the hydrogen evolution reaction (HER) utilizing renewable electricity. Previous research has identified a class of earth-abundant transition-metal dichalcogenide (TMD) nanocrystalline (NC) electrocatalytic materials that show great promise for the HER. The project will enable further advances in TMD-NC technology by employing a combination of in-situ analytical techniques coupled with theoretical calculations that will provide precise knowledge and understanding of the active catalytic sites in TMD NCs. Together with corresponding mechanistic understanding of the HER, the project will pave the way for the discovery and design of more efficient and less costly HER catalysts, thereby enabling the hydrogen economy. More broadly, the project includes educational, outreach, and workforce training initiatives supporting sustainable technologies for renewable energy and advanced catalysts. The overarching goal of this collaborative Early-concept Grants for Exploratory Research (EAGER) project is to establish an atomic-scale holistic understanding of the interplay between the structure, chemistry, catalytic activity, and mechanisms of the HER on 2H-MoS2 NC catalysts in real time. The team will accomplish this by employing a combination of in-situ electron paramagnetic resonance (EPR) spectroscopy and in-situ x-ray probes coupled with density functional theory (DFT) calculations. EPR spectroscopy will sensitively probe the local environment of paramagnetic catalytic sites, as well as their behavior in catalytic redox processes, under a wide range of operating conditions. In-situ x-ray techniques, complementary to in-situ EPR spectroscopy, will be employed to probe for the non-magnetic (i.e., non-EPR active species and other non-spin related factors) catalytically active HER species, and will enable the separation of the paramagnetic/spin effect from the overall catalytic activity. The changes in the EPR spectral properties, such as signal shape, width, intensity, and g-factor (Zeeman splitting) as a function of potential bias, time, and temperature, will be correlated with the measured HER activities to achieve the central goals of the proposal. DFT calculations will clearly identify the magnetic states of HER-active defect centers, correlate these magnetic states with the local environment of the defect, and calculate corresponding EPR spectra, taking into account the role of adsorbates, electrode polarization, and solvent screening. The outcomes of this research will resolve key challenges in understanding the catalytic activity of TMDs and provide fundamental insights that enable rational design of TMD-based electrocatalysts. Beyond the immediate focus on TMD electrocatalysis, the project will advance in-situ EPR as a promising tool for catalysis science. From the broader impacts perspective, the project will train the Hispanic student population (82%) at the University of Texas at El Paso in renewable energy research. Project-related educational material will be integrated with several outreach activities geared towards broadening participation of army personal and veterans at Fort Bliss in the El Paso region in scientific research. Educational modules on catalysis and its role in renewable energy will be developed and delivered at the University of Massachusetts, Amherst as part of the annual professional development workshops for K-12 STEM educators.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.

氢（H2）作为清洁能源和化学先驱的大规模部署将需要替换昂贵的铂群金属，这些金属通过氢进化反应（HER）催化水的电化学分裂，利用可再生电力。 先前的研究已经确定了一类富含地球的过渡金属二盐元素（TMD）纳米晶（NC）电催化材料，这对她来说表现出了很大的希望。 该项目将通过采用原位分析技术以及理论计算的结合来实现TMD-NC技术的进一步进步，这些计算将提供对TMD NC中主动催化位点的精确知识和理解。 该项目将与对她的相应的机械理解，为发现和设计更有效且成本较低的催化剂铺平道路，从而实现氢经济性。 更广泛地说，该项目包括支持可再生能源和高级催化剂可持续技术的教育，外展和劳动力培训计划。 这项合作的早期概念授予探索性研究（急切）项目的总体目标是建立原子级的整体理解，对建筑物，化学，化学，催化活性和她在2H-MOS2 NC催化剂上的结构，化学，催化活性和机制之间的相互作用。该团队将通过使用原位电子磁共振共振（EPR）光谱和原位X射线探针以及密度功能理论（DFT）计算的原位X射线探针来实现这一目标。 EPR光谱将在广泛的工作条件下敏感地探究顺磁催化位点的局部环境及其在催化氧化还原过程中的行为。原位X射线技术（与原位EPR光谱互补）将用于探测其物种的非磁性（即非EPR活性物种和其他非旋转相关因素）的物种，并将促进与整体催化活性分离的磁磁/旋转效应。 EPR光谱特性的变化，例如信号形状，宽度，强度和G因素（Zeeman拆分）随着潜在偏差，时间和温度的函数，将与测量的她的活动相关，以实现提案的核心目标。 DFT计算将清楚地识别出脑活动缺陷中心的磁状态，将这些磁状态与缺陷的局部环境相关，并计算相应的EPR光谱，并考虑到吸附物，电极极化和溶剂筛选的作用。这项研究的结果将解决关键挑战，以理解TMD的催化活性，并提供基本的见解，从而使基于TMD的电催化剂的理性设计。 除了直接关注TMD电催化外，该项目还将推进原位EPR，作为催化科学的有前途的工具。 从更广泛的影响角度来看，该项目将在德克萨斯大学埃尔帕索大学的可再生能源研究中培训西班牙裔学生人口（82％）。 与项目相关的教育材料将与几项旨在扩大科学研究的陆军个人和退伍军人在埃尔帕索地区的布利斯堡的参与的外展活动。关于催化及其在可再生能源中的作用的教育模块将在马萨诸塞大学（Amherst）开发和交付，这是K-12 STEM教育者年度专业发展研讨会的一部分。该奖项反映了NSF的法定任务，并通过该基金会的知识分子的优点和广泛的影响来评估NSF的法定任务，并被认为是值得的支持。