Georgetown College. Georgetown University.

Dr. YuYe Tong examines a slide with undergraduate student Jennifer Landon and graduate student Bingchen Du.
Undergraduate student Paul Kenyan discusses results from an experiment with Dr. YuYe Tong.
Transmission electron microscope images of platinum nanoparticles of different shape and size synthesized in Dr. Tong's laboratory. The black scale bars are equal to 10 nm.

"My work is fun and it provides a lot of learning opportunities even for myself. When you have the opportunity to understand a puzzle in your mind, that's the most rewarding part of the process."

Starting small and thinking big is the theme for Dr. YuYe Tong’s nanomaterials laboratory, where Dr. Tong, Associate Professor of Chemistry, and his students focus their fundamental research efforts on diverse metal nanoparticles. Though these particles are extremely small (about 100 thousandth the diameter of a human hair), gaining knowledge about their workings has important repercussions. One important area of research in the Tong lab focuses on platinum-based nanoscale electrocatalysts. By building a greater understanding of the workings of these platinum-based nanoparticles, the research of Dr. Tong and his students will enable scientists to maximize energy efficiency in real-world applications, such as fuel cells. In an age where energy resources are becoming more and more contested, this research is of utmost importance.

In order to move closer to an ultimate goal of rational design, making for maximally energy-efficient fuel cell electrocatalyts, a clear understanding of the intricacies of nanoparticle’s electrochemical characteristics and behavior is essential. Dr. Tong and his students focus their observations on nanoparticles composed of a maximum of three elements. Various research endeavors in the lab approach different aspects of metal nanomaterials and electrochemistry, including nanoscale single crystal ensemble catalysis, which focuses on tuning the catalytic activity of platinum nanoparticles by controlling their shape and size; the electrochemistry of ligand-protected nanoparticles; and charge transport through solid assemblies of nanoparticles, which have great fundamental ramifications in molecular electronics.

Of the importance of learning about nanoparticles, “there is a huge difference between macro- and nano-scale,” says Dr. Tong. The chemical reactions and other fundamental processes have a very different appearance when you go to the nano-scale, thus relying exclusively on data from the macro-scale will not allow scientists to optimize efficiency.

For their experiments and observations in nanoscale single crystal ensemble catalysis, Dr. Tong and his students synthetically produce platinum nanoparticles of different shapes (different orientations of surface structures) and sizes. They then use a powerful electron microscope to produce images of these platinum nanoparticles. These images allow Dr. Tong and his students to determine the size and the ensemble statistics of the shapes of the platinum nanoparticles. 

Dr. Tong and his students tune the catalytic activity of their platinum electrocatalyts by controlling their shape and size.The researchers collect data about how changes of shape and size of the nanoparticles influence reactivity and attempt to theorize relationships between the two. Fully aware of the imperfect nature of science, Dr. Tong encourages his students to forge arguments based on their findings, even if new findings may later require them to change their conclusions.

“Our ultimate goal,” says Dr. Tong, “is to figure out how to arrive at the most efficient and least expensive electrocatalyst for fuel cell applications. In order to reach a rational design of your material, you need to know what is active and what is not active in real-world working conditions.” Working from the same scale as the real-world applications (nano-scale, in this case) is the only way to accurately achieve this.

In another, related project, Dr. Tong and his students are working to try to understand the fundamental physics of ligand-protected metal nanoparticles. This research deals specifically with fundamentals that govern electron transfer across the metal-ligand interface, which models what happens at the metal-molecular wire junctions in molecular electronics. By controlling the interface, using different ligands and underlying metal elements, Dr. Tong and his students learn how to control the charge transfers.

“My work is fun and it provides a lot of learning opportunities even for myself,” says Dr. Tong. “When you have the opportunity to understand a puzzle in your mind, that’s the most rewarding part of the process.”

One unique feature of the Tong lab is its world-leading expertise in applying and developing electrochemical nuclear magnetic resonance (NMR), an emerging technique possessing great investigative power, combining the elegance of electrochemistry in controlling chemical environments with the exquisite chemical specificity and electronic structural sensitivity of NMR. Dr. Tong has made and continues to make significant original contributions to the development of this technique. An imposing superconducting magnet of an NMR spectrometer takes up a large space in the center of the lab. “It is a very expensive piece of equipment,” explains Dr. Tong. His lab has received regular funding from the National Science Foundation and the U.S. Department of Energy as well as various other research grants to support their work and to help pay for their equipment.

“In Dr. Tong’s Lab there is a good balance of work and play,” says Latoya Silverton, a junior working in his lab. “We meet once a week for group meeting when everything is down to business, and we get to observe and learn from each other’s work. Yet as a group we also celebrate birthdays, have dinners, go on ski trips, fishing trips and other fun activities. I think that such equilibrium is very important to healthy learning and development as an individual and as a group; we can communicate on a level of co-worker and friend.”

Dr. Tong is not only passionate about achieving electrocatalytic efficiency, he is passionate about achieving maximum efficiency in teaching as well. In Dr. Tong’s metal nanomaterials and electrochemical NMR lab, students are challenged both in their work with the precise and detail-oriented rigors of nano- and electrochemistry and to take charge of their own learning. Placing a strong emphasis on experiential (hands-on) learning, Dr. Tong empowers his students to do their best work possible, fostering a positive lab environment.

Dr. Tong attends workshops and conferences on undergraduate teaching and receives funding from the Center for New Designs in Learning and Scholarship at Georgetown for his efforts in alternative, efficient instruction in conjunction with initiatives such as Process Oriented Guided Inquiry Learning (POGIL) and Case Study. Dr. Tong cites findings that the success of students depends less on how good the teacher is than on how good the students are. With this in mind, he endeavors to help his undergraduates to learn to be good students (i.e., active learners). As the information in any field continues to grow, the lecture format becomes less effective and efficient as an educational tool, according to Tong. Rather than try to cover everything (an impossible task) Dr. Tong prefers to encourage his students to learn actively with self-motivated rigor, focusing on methods of inquiry, which the students can apply in approaching numerous different types of problems, questions, and experiments. Opposed to teaching that relies on lectures and simply relaying information, “what I preach is how to digest, correlate, and organically synthesize the available information that will help students to reach their own meaningful and self-consistent conclusions and make sensible predictions,” says Dr. Tong. “Imitation gives limited ability.”

For Dr. Tong, “The purpose of my exam is not to try to fail you but to put some pressure on you to learn to be an active learner.” When students take ownership of their learning, he knows he has done his job.

“Dr. Tong’s desire for students to think critically and problem solve is particularly important,” says Thuy Nguyen, another undergraduate in his lab. “He wants students to direct where their research is going.”

While different, this approach to teaching and learning has roots in ancient history. A student of Dr. Tong’s recently came back to him with a highlighted quote from Plato’s collected dialogues, describing Socrates’ method of teaching, telling him it reminded her of his class: “Truth cannot be taught, it must be sought. His only desire in talking to the boys was to make them use their minds. To him the best that could be done for them was to arouse them to think.”

Dr. Tong teaches undergraduate classes in Analytical Chemistry, Analytical Lab, Physical Chemical Measurements, and Instrumental Analysis and graduate classes in Advanced Analytical Methods and Advanced Topics in Electrochemistry.

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