• 2025~ Assistant Professor, MSE, KAIST

At the device level, I have expertise in designing composite materials with complex percolation pathways, as well as analyzing their mechanical and electrical responses under deformation. At the molecular level, I have designed inorganic molecular electrolytes and employed various analytical methods to investigate their ion dynamics. These areas of expertise provide unique and crucial perspectives for addressing the fundamental challenges in ion-tronics and solid-state battery systems.

• 2021~2025 Postdoc. Chemistry, University of Waterloo (Prof. Linda F. Nazar)

My research experience in polymer ion conductors and metal halide semiconductors has enabled me to expand my expertise toward developing superionic conductors (solid-state electrolytes), particularly those composed of metal halides and metal oxyhalides. During this period, I proposed a new molecular structure for an oxychloride-based inorganic ionic conductor that exhibits unprecedented viscoplasticity. Interestingly, we discovered that its unique mechanical behavior originates from a one-dimensional framework that allows reorientational motion similar to that of polymers. This new class of materials could provide an ultimate solution to one of the fundamental challenges in solid-state battery systems—the unreliable solid–solid interfacial contact. Subsequent in-depth studies are conducted to elucidate the mechanisms underlying the material’s exceptionally high ionic conductivity and to establish feasible synthesis pathways. 

A facile route to plastic inorganic electrolytes for all-solid state batteries based on molecular design (Energy & Environmental Science, 2025)

• 2020~2021 Postdoc. Chemical engineering, POSTECH (Prof. Yong-Young Noh)

After completing my Ph.D., I became intrigued by charge transport in ionic solids. In particular, I was curious about the advantages and disadvantages of ionic properties when holes are transported in semiconductors. Metal halide perovskite semiconductors and electrochemical transistors emerged as excellent model systems to explore this concept.

Toward high-performance p-type, tin-based perovskite thin film transistors (Applied Physics Letters, 2021)

• 2017~2018 Visiting researcher, Chemical engineering, Stanford (Prof. Zhenan Bao)

During this period, I realized the importance of developing intrinsically stretchable sensor systems to achieve mechanical toughness within a simple device structure, which is essential for the commercialization of such devices. Ion-conducting elastomers were employed as intrinsically stretchable active materials that maintain conductivity under deformation. In ion-conducting polymers, both ion diffusion and strain dissipation originate from molecular rearrangements of polymer chains; therefore, the fundamental motions governing ion transport and mechanical relaxation occur within the same spatial range. As a result, the percolation pathways for ion transport remain unaffected by strain. Furthermore, the frequency-dependent responsivity of ion conductors provides a unique advantage for realizing multimodal sensor systems, and I was the first to propose that relaxation time can serve as a strain-independent parameter. 

Self-healing electronic skin with high fracture strength and toughness (Nature Communications, 2024)

Artificial multimodal receptors based on ion relaxation dynamics (Science, 2020)

• 2015~2020 Graduate research assistant (Ph.D. course), MSE, POSTECH (Prof. Unyong Jeong)

In my early research, I focused on addressing the question: How can electronic devices be made mechanically deformable and stretchable? This work demonstrated new form-factor devices such as electronic skin (e.g., skin-attachable healthcare sensors) and robotic skin. Conductive percolation paths in polymer composites were designed at the macroscale to achieve target performance, and their influence on electrical properties under deformation was systematically investigated. In particular, the origins of viscoelasticity and viscoplasticity were studied and leveraged to realize mechanically adaptive devices. Various functional polymer films were fabricated through solution processes, carefully considering solvent–polymer orthogonality to ensure material integrity. 

Artificial multimodal receptors based on ion relaxation dynamics (Science, 2020)

Block copolymer elastomers for stretchable electronics (Accounts of Chemical Research, 2018)

E-skin tactile sensor matrix pixelated by position-registered conductive microparticles creating pressure-sensitive selectors  (Adv. Funct. Mater. 2018)

Stretchable E-Skin Apexcardiogram Sensor (Advanced Materials 2016)

• 2021 Top 10 nanotechnology, Korea Nanotechnology Research Society

• 2021 Young Scientist Award, IC ME&D, Korea

• 2021 Basic Science Research Program for Postdoctoral Fellowship (3 years), NRF Korea

• 2021 POSTECH Initiative for fostering Unicorn of Research & Innovation PostDoc Fellowship

• 2020 Silver Prize in 26th Humantech Paper Award, Samsung Electronics

• 2017 Go Jun Sik Scholarship, MSE, POSTECH

• 2016 Promising Young Scientist of Korea, The Korean Academy of Science and Technology (KAST)

I believe the qualities required of a researcher in the coming AI era are different from what they have been.

In the past, a student was someone who received knowledge under the guidance of professors and senior colleagues. But we have entered an era where learning itself can be done with the help of AI. And as a world-leading research institution, KAIST's role is, I believe, not merely to master what is already known but to create knowledge that does not yet exist. For this reason, rather than students who simply follow established knowledge, I want to work with those who wonder, "How can we create new and meaningful materials, and put them to use?" This is a judgment that weighs the research one genuinely finds exciting, the work that is scientifically and technically meaningful, and what the wider industry needs.

With the help of AI, I believe we are moving toward a time when professors and student researchers can discuss ideas on equal footing. In such an environment, what sets a researcher apart is not the amount of knowledge they hold, but the willingness to judge for themselves and the judgment they build upon it. So if you join our lab, I hope you will bring more than the ability to complete assigned tasks: I hope you will ask your own questions and seek out your own research direction. And because research is, in the end, something carried out among people, the ability to express your own views clearly and persuade others will only grow more important for the researcher of the future.

Along the way, rather than making your decisions for you, I want to be someone who helps you build the ability to decide for yourself. Among countless possible research directions, I will help you gauge which problems are genuinely worth pursuing. Together we will develop the discernment to tell a merely plausible result from a truly meaningful discovery, the judgment to know which questions are worth solving and which data are worth trusting. And above all, I want to be a true intellectual sparring partner: a colleague who challenges your ideas and helps you sharpen them.

앞으로의 AI 시대에 연구자에게 요구되는 자질은 지금까지와는 다르다고 생각합니다.

과거의 학생은 교수와 선배의 지도를 받으며 지식을 전수받는 존재였습니다. 하지만 이제 학습 그 자체는 AI의 도움으로 충분히 해낼 수 있는 시대가 되었습니다. 이때 세계적인 선두 연구기관인 카이스트가 맡아야 할 역할은, 이미 있는 지식을 익히는 데서 나아가 아직 없는 지식을 새로 만들어내는 것이라 생각합니다. 그래서 저는 기존의 지식을 기반으로, "어떻게 새롭고 의미 있는 소재를 만들고 또 응용할 수 있을까"를 궁금해하는 학생과 함께하고 싶습니다. 이는 본인이 재미를 느끼는 연구, 과학적·공학적으로 의미 있는 일, 그리고 산업적으로 필요한 일을 두루 고려한 판단이 될 것입니다.

AI의 도움으로 앞으로 교수와 학생 연구자가 대등한 지식 수준에서 토론할 수 있는 시대가 올 것이라 생각합니다. 이런 환경에서는 지식의 양보다, 스스로 판단하려는 태도와 그 위에서 길러진 판단 능력이 연구자를 가릅니다. 그래서 우리 연구실에 오는 학생이라면, 주어진 일을 해내는 데 그치지 않고 스스로 질문을 던지고 자신의 연구 방향을 찾아가려는 태도를 갖추기를 바라고 있습니다. 또한 과학 및 공학 연구는 연구자들 간 의견 교류에서 많은 시너지가 발생하는 만큼, 자신의 의견을 분명히 피력하고 상대를 설득해 가는 능력 역시 앞으로의 연구자에게 점점 더 중요한 자질이 될 것이라 생각합니다.

저는 그 과정에서, 여러분의 판단을 대신 내려주기보다 여러분이 스스로 판단할 수 있는 능력을 길러주는 사람이 되고자 합니다. 무수히 많은 연구 방향 중에서 무엇이 정말 가치 있는 문제인지 여러분과 함께 가늠하겠습니다. 그저 그럴듯해 보이는 결과와 진짜 의미 있는 발견을 구별하는 안목, 어떤 질문이 풀 만한 가치가 있고 어떤 데이터가 신뢰할 만한지를 판별하는 기준을 함께 세워 가겠습니다. 그리고 무엇보다, 동료로서 여러분과 아이디어를 부딪히며 그 생각을 더 날카롭게 다듬어 가는 토론의 상대가 되겠습니다.

- Insang You, 2026