5. One semester more at EWHA

· Where: Advanced Nanomaterials 21 Lab, Ewha Womans University

· When: Dec. 24th. 2018 ~ June. 30th. 2019

· Topic: Anchoring Pt single-atom on the TiO1-xNx nanosheet for efficient hydrogen evolution reaction catalyst

1) Reasons why I continued my studies in the same lab

The main reason was the research areas of this lab, which were heavily focused on environmental applications. Since I have just started to know a little bit about photocatalyst, electrocatalysts, and metal-ion batteries, I wanted to study them deeply. I felt that these topics would be highly essential to replace current fossil fuels with carbon-free energy, so I wanted to explore deeper by studying in the same field. So, to do that, I need to study at graduate school. Other minor reasons are the lab members who seemed friendly and the size of the lab. It was quite a big and famous lab among chemistry undergraduates.

2) Things that I learned

· Topics

- Electrochemistry: Thermodynamics and kinetics of electrode reaction

- Batteries: Li-Ion battery, Li-Air battery

- Single-atom catalyst

- Solid-state chemistry: synthesis, characterization tools, unit cell, diffraction selection rule

- Surface defect, vacancy, active site, and electron configuration

· Methods

- Many more solid-state reactions: TiO2 nanosheet, LiCoO2, Na0.7CoO2, NaRuO2, Na2Ti3O7

- Hydrothermal reaction

- Electrodeposition: Finding proper electrode, solvent, voltage, time, etc.

· Measurement

- Training for XANES and EXAPS at Pohang Accelerator Laboratory

- Training for SEM, EDS

- Characterization with XRD: lattice parameters, d-spacings, grain size

- Zeta potential

- UV-Vis spectrometer

- Infra-Red spectrometer

3) Looking back on my first semester

First, during the six months, I could learn the basic attitude as an independent researcher - how a researcher should study and implement experiments. As I learned specific experimental skills from a senior Ph.D. student who has been studied in this lab for a long time, I could have lots of chances to discuss with her as well. She not only helped me to reduce unnecessary trials but also considered me as an independent researcher. We discussed possible alternatives and talked about our current and future as well. She also helped me find related articles easily. It was fun to talk to her, thinking about the possible hypotheses, and planning the next steps for my experiments. Thanks to her, I learned how to concentrate on the mechanisms and think creatively.

Another important thing that I learned is that I got to know myself better. At first, I was not sure whether being a researcher would fit me. But, I realized that I liked to study independently: looking at different textbooks and journals, having discussions with others, planning my schedule, and implementing it. Second, I realized that motivation was the most important driving force to pursue my research continuously. In particular, I get motivated by the fact that I am contributing and will contribute more to the future of humankind. That was the push for the eight months of study.

4) But, to a different way

Last semester was one of the most life-changing periods of my life. Everything went so fast that I couldn't believe all those ups and downs went through me. My situation changed drastically since my supervisor was planning to move to another university, and this summer, he moved. So, I made up my mind to take a semester break and work in an outside research center. Although I could work at other professors' lab at Ewha, I just wanted to challenge myself. Besides, I looked for new research topics, which focused on urgent environmental problems, and this time, a more interdisciplinary one.

Thus, I grabbed the chance to work as a research assistant at KIST, a prominent and well-known national research center. Luckily, I am participating in the governmental research project called 'VKIST,' which aim for a better water management system in the Mekong delta region, Vietnam. Hence, I am now working on the modification of membrane for the membrane distillation at the Center for Water Resource Cycle Research.