Manipulation of Intraparticle Charge Delocalization by Conjugated Metal-Ligand Interfacial Bonds

通过共轭金属-配体界面键操纵粒子内电荷离域

• 批准号: 1710408
• 负责人: Shaowei Chen
• 金额: $ 28万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1710408&HistoricalAwards=false
• 关键词: Manipulation; Intraparticle; Charge; Delocalization; Conjugated

Nanoscaled particles, having dimensions on the order of a billionth of a meter, show many technologically important properties, and are therefore actively under research. Dr. Shaowei Chen of the University of California Santa Cruz (UCSC) studies transition metal nanoparticles that are stabilized with an organic capping layer (the ligand), making the capped nanoparticles dispersible in common solvents and useful in many applications. Dr. Chen's research shows that the chemical bonds between the metal nanoparticle cores and the organic ligands can be exploited as a new, effective way of manipulating nanoparticle properties. In this project, Dr. Chen and his students are interested in examining the fundamental chemical nature of the nanoparticle-ligand interfacial bonds and examining the impacts of nanoparticle core metals and core size on the formation of the bonds. Results from these studies are critical to the establishment of a correlation between the nanoparticle structures and properties that will enable the nanoparticles to be used in optical devices, sensors and other advanced applications. As charge transfer is a fundamental process in a wide range of important applications where nanoparticle materials are unique building blocks, it is envisioned that research on nanoparticles may have impacts on the electronics and energy industries, health care, and homeland security. Dr. Chen involves high school, undergraduate and graduate students in his research and actively participates in various outreach programs such as the UCSC ACCESS, UC LEADS, (the University of California Leadership Excellence through Advanced Degrees), the Summer Internship Program (SIP) and California State Summer School for Mathematics (COSMOS) programs. In this research program, Dr. Shaowei Chen of the University of California Santa Cruz (UCSC) is supported by the Macromolecular, Supramolecular and Nanochemistry (MSN) Program to study the impacts of metal-ligand interfacial bonding interactions on the nanoparticle chemical and physical properties. Dr. Chen has developed new surface adsorption chemistries in which metal-carbon, -oxygen, or -nitrogen covalent bonds readily form to result in the passivation and functionalization of transition-metal nanoparticles consisting of ruthenium, platinum and copper and combinations of core/shell, and core/shell/shell architectures. The reduced interfacial resistance resulting from the functionalization facilitates interparticle charge transfer, in sharp contrast to nanoparticles functionalized with the more commonly used mercapto derivatives. In particular, the formation of conjugated metal-ligand interfacial bonds leads to effective intraparticle charge delocalization between particle-bound functional moieties, and the emergence of optical and electronic properties that are analogous to those of their dimeric counterparts. Dr. Chen's research advances the understanding of the fundamental chemical nature of the interfacial bonds and examines the impact of nanoparticle core metals and core size on the formation of conjugated metal-ligand interfacial bonds. Results from these studies are critical in the establishment of an unambiguous correlation between the nanoparticle structures and properties. Dr. Chen involves high school, undergraduate and graduate students in his research and actively participates in various outreach programs such as the UCSC ACCESS, UC LEADS, (the University of California Leadership Excellence through Advanced Degrees), the Summer Internship Program (SIP) and California State Summer School for Mathematics (COSMOS) programs.

纳米级颗粒的尺寸约为十亿分之一米，具有许多技术上重要的特性，因此正在积极研究。加州大学圣克鲁斯分校 (UCSC) 的 Shaowei Chen 博士研究了用有机覆盖层（配体）稳定的过渡金属纳米颗粒，使覆盖的纳米颗粒可分散在常见溶剂中并可用于许多应用。 陈博士的研究表明，金属纳米颗粒核和有机配体之间的化学键可以作为操纵纳米颗粒特性的一种新的、有效的方法。在这个项目中，陈博士和他的学生有兴趣研究纳米粒子-配体界面键的基本化学性质，并研究纳米粒子核心金属和核心尺寸对键形成的影响。这些研究的结果对于建立纳米颗粒结构和特性之间的相关性至关重要，这将使纳米颗粒能够用于光学设备、传感器和其他先进应用。由于电荷转移是纳米粒子材料是独特构建块的各种重要应用中的基本过程，因此可以预见，纳米粒子的研究可能会对电子和能源工业、医疗保健和国土安全产生影响。陈博士让高中生、本科生和研究生参与他的研究，并积极参与各种外展项目，如 UCSC ACCESS、UC LEADS（加州大学卓越领导力高级学位）、暑期实习计划 (SIP) 和加州数学暑期学校 (COSMOS) 项目。在该研究项目中，加州大学圣克鲁斯分校（UCSC）的陈少伟博士得到了高分子、超分子和纳米化学（MSN）项目的支持，研究金属-配体界面键合相互作用对纳米颗粒化学和物理性质的影响。陈博士开发了新的表面吸附化学，其中金属-碳、-氧或-氮共价键很容易形成，从而导致由钌、铂和铜以及核/壳和核/壳/壳结构组合组成的过渡金属纳米颗粒的钝化和功能化。 官能化导致的界面电阻降低有利于颗粒间电荷转移，这与用更常用的巯基衍生物官能化的纳米颗粒形成鲜明对比。 特别是，共轭金属-配体界面键的形成导致颗粒结合的功能部分之间有效的颗粒内电荷离域，并出现类似于其二聚体对应物的光学和电子特性。陈博士的研究增进了对界面键基本化学性质的理解，并研究了纳米颗粒核心金属和核心尺寸对共轭金属-配体界面键形成的影响。这些研究的结果对于建立纳米颗粒结构和性质之间的明确相关性至关重要。陈博士让高中生、本科生和研究生参与他的研究，并积极参与各种外展项目，如 UCSC ACCESS、UC LEADS（加州大学卓越领导力高级学位）、暑期实习计划 (SIP) 和加州数学暑期学校 (COSMOS) 项目。

项目成果

Cobalt oxides nanoparticles supported on nitrogen-doped carbon nanotubes as high-efficiency cathode catalysts for microbial fuel cells

• DOI: 10.1016/j.inoche.2019.04.036
• 发表时间: 2019-07
• 期刊: Inorganic Chemistry Communications
• 影响因子: 3.8
• 作者: Wei Yang;J. Lu;Yudong Zhang;Yi Peng;Rene Mercado;Jun Li;Xun Zhu;Shaowei Chen

Platinum nanoparticles encapsulated in nitrogen-doped graphene quantum dots: Enhanced electrocatalytic reduction of oxygen by nitrogen dopants

• DOI: 10.1016/j.ijhydene.2017.10.078
• 发表时间: 2017-12
• 期刊: International Journal of Hydrogen Energy
• 影响因子: 7.2
• 作者: Limei Chen;Yi Peng;Jia-En Lu;Nan Wang;Peiguang Hu;Bingzhang Lu;Shaowei Chen

Ruthenium Ion-Complexed Graphitic Carbon Nitride Nanosheets Supported on Reduced Graphene Oxide as High-Performance Catalysts for Electrochemical Hydrogen Evolution

• DOI: 10.1002/cssc.201701880
• 发表时间: 2018-01-10
• 期刊: CHEMSUSCHEM
• 影响因子: 8.4
• 作者: Peng, Yi;Pan, Wanzhang;Chen, Shaowei
• 通讯作者: Chen, Shaowei

Photo-enhanced antibacterial activity of ZnO/graphene quantum dot nanocomposites

• DOI: 10.1039/c7nr07367d
• 发表时间: 2018-01-07
• 期刊: NANOSCALE
• 影响因子: 6.7
• 作者: Liu, Junli;Rojas-Andrade, Mauricio D.;Chen, Shaowei
• 通讯作者: Chen, Shaowei

Silicene Quantum Dots: Synthesis, Spectroscopy, and Electrochemical Studies

• DOI: 10.1021/acs.langmuir.7b04253
• 发表时间: 2018-02-27
• 期刊: LANGMUIR
• 影响因子: 3.9
• 作者: Hu, Peiguang;Chen, Limei;Chen, Shaowei
• 通讯作者: Chen, Shaowei