Electrochemical Liquid-Liquid-Solid Growth of Intermetallic Nanocrystals from Liquid Metal Alloys

在化学系大分子、超分子和纳米化学计划的支持下，密歇根大学的斯蒂芬·马尔多纳多博士正在融合一套不同的方法和工具来开发由多种金属组成的纳米结构。这些金属间化合物纳米结构是通过在纳米级液态金属液滴中进行的电化学反应来合成的。对电化学参数的控制允许成分和结构的可调编程。此外，正在探索在电化学控制下在液态金属界面上合成二维材料，以开发用于合成金属间纳米结构的替代合成工具箱。通过这项研究，学生们正在学习如何在不干扰反应的情况下合成和表征纳米结构。马尔多纳多博士继续通过K-12活动以及开发与电化学和纳米科学有关的数字内容，与更广泛的社区接触和教育。这项研究致力于推进电化学液-液-固(EC-LLS)过程形成金属间化合物晶体纳米结构的机理理解和合成范围。目标是两个关键的发展。首先，通过X射线反射率的表征，探索了用EC-LLS方法合成二维铅晶体(如铅)。其次，采用原位液体电化学透射电子显微镜记录单个金属间化合物纳米颗粒的生长事件。参与这项工作的研究人员接受了电化学、材料、冶金、纳米科学、固态化学、X射线反射率和透射电子显微镜方面的培训。参与这项工作的所有研究人员都参与了向小学生介绍电化学和纳米科学奇观的互动活动的发展。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Macromolecular, Supramolecular, and Nanochemistry Program in the Division of Chemistry, Dr. Stephen Maldonado of the University of Michigan is merging a diverse set of approaches and tools to develop nanostructures that are composed of multiple metals. These intermetallic nanostructures are synthesized using electrochemical reactions performed in nanoscale liquid metal droplets. Control over electrochemical parameters allows for tunable programming of both composition and structure. In addition, the synthesis of two-dimensional materials at liquid metal interfaces under electrochemical control is being explored for the development of an alternative synthetic toolbox for synthesizing intermetallic nanostructures. Through this research, students are learning how to synthesize and characterize nanostructures without disturbing the reaction. Dr. Maldonado continues to engage and educate the broader community through K-12 activities as well as through the development of digital content related to electrochemistry and nanoscience. This research focuses on advancing the mechanistic understanding and synthetic scope of the electrochemical liquid-liquid-solid (ec-LLS) process for the formation of intermetallic crystalline, nanostructures. Two key developments are being targeted. First, the ec-LLS method is being explored for the synthesis of two-dimensional Pb crystals (e.g. plumbene) through characterization by X-ray reflectivity. Second, in-situ liquid electrochemical transmission electron microscopy is employed to record individual intermetallic nanoparticle growth events by ec-LLS. Researchers involved in this work are trained in electrochemistry, materials, metallurgy, nanoscience, solid-state chemistry, X-ray reflectivity, and transmission electron microscopy. All researchers involved in this work assist in the development of interactive activities that introduce the wonders of electrochemistry and nanoscience to elementary school students.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.