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北京时间2023年6月2日晚八点，iCANX Talks 第146期邀请到莱斯大学Matthew R. Jones教授分享Au32团簇颗粒、阿贡国家实验室Tongchao Liu教授分享电池性能的衰减关键机制。更多精彩，敬请期待！

【嘉宾介绍】

Matthew R. Jones

Rice University

Towards Atomically-Precise Nanoparticle Synthesis

【Abstract】

Seed-mediated synthesis strategies, in which small nanoparticle precursors are added to a growth solution to initiate heterogeneous nucleation, are among the most ubiquitous, simple, and productive methodologies for generating well-defined colloidal anisotropic nanostructures. However, the size, structure, and chemical properties of the seeds remain poorly understood, which partially explains the lack of mechanistic understanding of many particle growth reactions. Here, we identify an atomically-precise gold cluster as the majority component of the seed solution that has been widely used in anisotropic gold nanoparticle syntheses over the last two decades.

种子生长法是目前最常见、简单以及高效的各向异性胶体结构的制备方法。生长过程中通常需要利用将小的金属颗粒前体加入生长溶液中从而实现异相成核。然而，种子的尺寸，结构以及化学性质目前仍然很少被研究理解，这也是金属纳米颗粒生长机理仍然缺位的原因之一。为此，我们研究并发现Au32团簇颗粒是过去二十年中被广泛应用的一种金纳米颗粒种子中的重要组成部分。

Mass spectrometry and transmission electron microscopy allow for the assignment of the cluster as having a 32 atom Au core with 8 halide ligands and 12 neutral ligands constituting a bound ion pair between a halide and the cationic surfactant: Au32X8[AQA+•X-]12 (X = Cl, Br; AQA = alkyl quaternary ammonium). Ligand exchange is dynamic and versatile, occurring on the order of minutes and allowing for the formation of 48 distinct mixed-ligand clusters.

质谱以及透射电子显微镜结果证明了这个团簇由32个金原子和8个卤素配体以及12个中性配体构成，其中卤素阴离子和表面活性剂阳离子形成离子配对结构Au32X8[AQA+•X-]12 （X = Cl, Br; AQA = 烷基叔胺盐离子）。这种团簇的配体交换速度非常快，在分钟尺度上发生并且实现48种不同的混合配体团簇。

Anisotropic nanoparticle syntheses seeded with solutions enriched in Au32 show narrower size distributions and fewer impurity particle shapes, indicating the importance of this cluster as a precursor to the growth of well-defined nanostructures. These results establish the importance of characterizing structures on the ~1 nm length scale for understanding nanosynthesis mechanisms and points towards a future with atomic control over colloidal growth reactions.

利用Au32团簇合成的均相异性纳米颗粒展现出了更窄的尺寸分布和更少的杂质，指明了团簇作为前体在合成结构确定的纳米结构的重要作用。这些结果搭建了表征1纳米尺度下金纳米结构的方法，并且为理解纳米粒子合成机理建立了重要基础，为未来原子级精准控制胶体颗粒的生长指明了方向

【BIOGRAPHY】

Matt Jones is an Assistant Professor of Chemistry and Materials Science & Nanoengineering at Rice University. The expertise of his research group covers the fields of inorganic nanoparticle synthesis, surface chemistry, liquid-phase transmission electron microscopy, and nanoscale self-assembly. Matt is known for discovering an atomically-precise gold nanocluster as a precursor in the synthesis of anisotropic nanostructures and developing methods to assemble nanoparticles into chiral superlattice phases for the high-throughput fabrication of plasmonic metamaterials.

马特·琼斯是莱斯大学化学系以及材料与纳米工程系助理教授。他的课题组专攻于无机纳米颗粒的制备，表面化学，液体透射电子显微镜以及纳米尺度上的自组装。他的代表性工作包括发现了金团簇是金纳米颗粒合成中种子的重要组成部分，通过手性自组装方法实现高通量的等离子基元超材料制备。

He is the recipient of numerous awards and honors including the Packard Fellowship for Science & Engineering, an NSF CAREER award, a Victor K. LaMer Award Finalist, an Arnold O. Beckman Postdoctoral Fellowship, and an NSF Graduate Research Fellowship. He graduated from Carneige Mellon University with B.S. degrees in both Materials Science and Biomedical Engineering, he received his Ph.D. from Northwestern University under the guidance of Chad Mirkin, and completed a postdoctoral fellowship with Paul Alivisatos at UC Berkeley before starting his independent career at Rice.

目前，他是Packard Fellowship for Science & Engineering，NSF CAREER award，Victor K. LaMer Award， Arnold O. Beckman Postdoctoral Fellowship，以及NSF Graduate Research Fellowship等多项大奖的获得者。琼斯教授本科毕业于卡耐基梅隆大学并获得材料化学和生物医药工程双学位，在Chad Mirkin教授指导下获得西北大学的博士学位。在莱斯大学独立建组之前，他在加州大学伯克利分校Paul Alivisatos教授课题组完成博后研究。

Tongchao Liu

Argonne National Laboratory

Rational Composition and Structure Designs for High Performance Li-ion batteries

【Abstract】

Since its birth nearly three decades ago, lithium-ion battery (LIB) has changed all aspects of our life, from portable electronics, electric vehicles (EVs) to large-scale energy storage systems and the emerging electric flight applications. Currently, the bottleneck of the energy density of LIB is set by the intercalation cathode materials, which has been a significant push to develop high energy density and low-cost cathodes in response to rapidly expanding market.

自锂离子电池的诞生近三十年以来，它已经被广泛的应用到便携式电子产品、电动汽车 (EV)大型储能系统和新兴的电动飞行应用，并改变了我们生活的方方面面。目前，锂离子电池能量密度的瓶颈是正极材料，因此需要大力推动高能量密度、低成本正极材料的发展来应对市场的快速扩张。

In this talk, I will focus on the identification of key failure modes and development of mitigation strategies for facilitating the future application of battery technologies. I will present some insights into the failure mechanism of battery materials that differ from the existing paradigms. Further, I will discuss how we can utilize rational composition and structure design to improve energy density, battery life without compromising safety, speed up battery charging, and reduce the cost of batteries.

在这个报告中，我将重点关注电池性能的衰减关键机制的研究并在此基础上探究提升电池性能的策略的，以促进电池技术的未来更广泛的应用。在本文中，我将介绍一些与现有范式不同的电池材料失效机制的见解。此外，我将进一步讨论我们如何通过合理的成分和结构调控来全面提升提高能量密度、电池寿命、加快电池充电速度并降低电池成本。

【BIOGRAPHY】

Dr. Tongchao Liu is currently an assistant chemist at Argonne National Laboratory. He has over 10-years of research experience in designing and synthesizing multifunctional materials for energy storage and utilizing cutting-edge characterization techniques to elucidate in-depth mechanistic understanding of the relationship between structures and performance, and to provide guidance and approaches to design and synthesize better battery materials with higher energy density and improved safety.

刘同超博士是美国阿贡国家实验室的助理化学家。他在设计和合成多功能电化学储能材料方面拥有超过 10 年的研究经验。他致力于利用尖端表征技术阐明对结构和性能之间关系的深入机理理解，并为设计和合成具有更高能量密度和更高安全性的电池材料提供指导和方法。

Dr. Liu held 5 US patents and published more than 90 research papers published in numerous prestigious international academic journals including "Nature (3)", “Nature Energy (3)” "Nature Nanotechnology", “Nature Sustainability”, "Nature Communications (6)", "Advanced Materials", and "Proceedings of the National Academy of Sciences". Aside from academic achievements, he is actively involved in scientific activities serving as editors for Nano Energy and Materials Today Energy and Young Advisory Board Members for Carbon Energy, International Journal of Extreme Manufacturing and Carbon Neutralization.

刘博士拥有5项美国专利并发表超过90篇文章，包括在Nature (3)、Nature Energy (3)、Nature Nanotechnology、Nature Sustainability、Nature Communications (6)、Advanced Materials和Proceedings of the National Academy of Sciences。除了学术成就，他还积极参与科学活动，担任 Nano Energy 和 Materials Today Energy 的编辑以及 Carbon Energy、International Journal of Extreme Manufacturing 和 Carbon Neutralization 的青年编委。