Collaborative Research: SusChEM: Engineering Charge Transport through Directed Orientation of Transition Metal Dichalcogenide Catalysts

合作研究：SusChEM：通过过渡金属二硫属化物催化剂定向定向进行工程电荷传输

• 批准号: 1703655
• 负责人: Dunwei Wang
• 金额: $ 13.47万
• 依托单位: Boston College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1703655&HistoricalAwards=false
• 关键词: Collaborative; Research; SusChEM; Engineering; Charge

The project will investigate new materials and catalyst structures for the efficient photocatalysis and photoelectrocatalysis of chemical reactions of importance for the production of clean energy from the sun and other renewable or sustainable resources. The research will also have applicability to a number of technologies of importance to the Nation's economic competitiveness and resource utilization, including energy storage, photovoltaics, and optoelectronics. In addition, educational and outreach activities will be incorporated, including both graduate and undergraduate student training, a K-12 workshop on interactive photocatalytic energy conversion, and summer research opportunities for high-school students. The project investigates the transition metal dichalcogenide (TMDC) catalyst tungsten disulfide (WS2) for the electrocatalytic hydrogen evolution reaction and the photocatalytic reduction of water to produce hydrogen as a renewable component of fuels and chemicals. Specifically, a unique edge-on orientation of the nanoscale WS2 catalyst particles with respect to their supporting charge transfer material will be investigated to achieve dramatically higher reaction rates than obtainable with conventional flat particle oriented catalysts. The dichalcogenides are known to be active due to the high catalytic activity of their edge sites when supported on a semiconductor, metal, or carbon material. Maximization of performance in these applications requires rapid charge transfer across the TMDC/support interface. However, for the typical orientations of TMDCs in most electro- and photocatalysts, the interfacial charge transfer is especially slow, since it must occur across the inert TMDC basal plane. The research will test the hypothesis that the rates of charge transfer across the WS2-support interface will be increased by an edge-on orientation of the WS2 layers due to interfacial bonding, and that this rate can be tuned by controlling the edge termination of the WS2 layers. The study will build upon the investigators' preliminary results showing promising photocatalytic activity of WS2 nanotube-arrays, in which the WS2 layers are in an edge-on orientation. These WS2 nanotubes will be used as a platform to design and synthesize novel Janus-type photoelectrodes and photocatalyst particles containing tailored interfaces. To gain fundamental understanding of these interfaces and guide their design, the investigators have prepared model systems consisting of WS2 single-crystals in either a basal plane or edge-on orientation. They will create WS2-semiconductor, metal or carbon interfaces by depositing these materials on top of the model WS2 systems and will measure the influence of WS2 orientation, defects, and edge termination on charge transfer and recombination rates at the interface. They will also perform measurements and modeling to understand these rates in terms of underlying factors including interfacial bonding and separation distance, interfacial dangling bonds and their electronic energies, and step changes in electrical potential energy and local electric field at the interface.

该项目将研究新的材料和催化剂结构，用于有效地催化和光电催化化学反应，这些化学反应对于从太阳和其他可再生或可持续资源中生产清洁能源具有重要意义。该研究还将适用于对国家经济竞争力和资源利用具有重要意义的许多技术，包括能源储存、光电子学和光电子学。 此外，还将纳入教育和宣传活动，包括研究生和本科生培训，K-12互动光催化能源转换研讨会以及高中生夏季研究机会。该项目研究了过渡金属二硫属化物（TMDC）催化剂二硫化钨（WS 2）用于电催化析氢反应和光催化还原水以产生氢气作为燃料和化学品的可再生成分。 具体地，将研究纳米级WS 2催化剂颗粒相对于其支撑电荷转移材料的独特的边缘取向，以实现比用常规扁平颗粒取向催化剂可获得的显著更高的反应速率。已知二硫属化物是活性的，这是由于当负载在半导体、金属或碳材料上时其边缘位点的高催化活性。 这些应用中的性能最大化需要跨TMDC/支持接口的快速电荷转移。然而，对于大多数电催化剂和光催化剂中TMDC的典型取向，界面电荷转移特别慢，因为它必须跨越惰性TMDC基面发生。 该研究将测试的假设，即跨WS 2支持界面的电荷转移速率将增加的WS 2层的边缘上的取向，由于界面结合，并且该速率可以通过控制WS 2层的边缘终止进行调整。 该研究将建立在研究人员的初步结果的基础上，这些结果显示WS 2纳米管阵列具有良好的光催化活性，其中WS 2层处于边缘取向。这些WS 2纳米管将被用作设计和合成新型Janus型光电极和含有定制界面的光催化剂颗粒的平台。为了获得对这些界面的基本理解并指导其设计，研究人员准备了由基底平面或边缘取向的WS 2单晶组成的模型系统。他们将通过在模型WS 2系统顶部沉积这些材料来创建WS 2-半导体，金属或碳界面，并将测量WS 2取向，缺陷和边缘终止对界面处电荷转移和复合速率的影响。他们还将进行测量和建模，以了解这些速率的基本因素，包括界面键合和分离距离，界面悬挂键及其电子能量，以及界面处电势能和局部电场的阶跃变化。

项目成果

Catalysts in electro-, photo- and photoelectrocatalytic CO2 reduction reactions

电催化、光催化和光电催化 CO2 还原反应中的催化剂

• DOI: 10.1016/j.jphotochemrev.2019.02.002
• 发表时间: 2019-09
• 期刊: Journal of Photochemistry and Photobiology C: Photochemistry Reviews
• 作者: Wang Yawen;He Da;Chen Hongyu;Wang Dunwei
• 通讯作者: Wang Dunwei

Photo-Induced Performance Enhancement of Tantalum Nitride for Solar Water Oxidation

• DOI: 10.1016/j.joule.2017.09.005
• 发表时间: 2017-12-20
• 期刊: JOULE
• 影响因子: 39.8
• 作者: He, Yumin;Ma, Peiyan;Wang, Dunwei
• 通讯作者: Wang, Dunwei

Facet-Dependent Kinetics and Energetics of Hematite for Solar Water Oxidation Reactions

• DOI: 10.1021/acsami.8b05190
• 发表时间: 2019-02-13
• 期刊: ACS APPLIED MATERIALS & INTERFACES
• 影响因子: 9.5
• 作者: Li, Wei;Yang, Ke R.;Wang, Dunwei
• 通讯作者: Wang, Dunwei