Ungyu Paik

Ungyu Paik is a distinguished professor in the Department of Energy Engineering at Hanyang University, Korea. He earned his Ph.D. in the Department of Ceramic Engineering from Clemson University (1988 ~ 1991). Following this, he served as an associate professor at Changwon National University, Korea, until 1999. In that year, he became a professor at Hanyang University. The expertise of Professor Paik was acknowledged when he served as a minister in the Ministry of Trade, Industry, and Energy of Korea (2017 ~ 2018). Upon returning to academia, he has engaged in collaborative research with leading global companies, such as Samsung SDI, Samsung electronics and LG energy solution, making substantial contributions to the battery industries and broader energy sector.

His research interests are centered around the exploration and development of materials for advanced Li-ion batteries and next-generation energy storage systems. Based on the fundamental understanding of the physical and electrochemical properties of the materials, his research has encompassed various aspects of advanced Li-ion batteries. These include the engineering electrode components (cathode/anode active materials, binder, conducting agent) and improving Li-ion/electron transport kinetics within electrode. Recently, he has directed his focus towards the advancement of next-generation energy storage systems. These include all-solid-state batteries (ASSB) with sulfide and oxide-based solid electrolytes, roll-to-roll dry coating process, Li-metal/sulfur/air batteries, sodium batteries, liquid metal batteries, flow electrode capacitive mixing (F-CapMix) and proton conducting fuel cell (PCFC), designed for low-cost and sustainable energy devices.

His work extends further into the synthesis of electro-catalyst for hydrogen evolution and oxygen reduction reactions in the field of water splitting. Until now, he has published over 400 papers, with h-index exceeding 70, and over 200 granted patents and patent applications. Acknowledging his dedication to academic research, he has consistently been recognized as a highly cited researcher (HCR) by Clarivate Analytics, consistently ranking in the top 1% of scientists in the “Crossfield” for four consecutive years (2020 ~ 2023). His substantial contributions to energy storage systems solidify his position as a distinguished professor and researcher in his field.

ABSTRACT

Nanoparticles engineering toward NT and ET applications

The importance of nanoparticle engineering in the fields of semiconductor fabrication and Li-ion battery (LiB) applications will be discussed as follows:

(1) Semiconductor: Molybdenum (Mo) is a promising candidate for replacing tungsten in sub-3nm logic and 3D memory devices due to its low resistivity and superior gap-filling ability. However, during the chemical mechanical planarization (CMP) process, the instability of nanoparticles in a suspension and high dissolution rate of Mo films hinder its practical use. This presentation will discuss the importance of nanoparticle engineering in CMP, highlighting its potential to improve CMP performances, increase yield, and enhance compatibility with sub-3nm devices.

(2) LiBs: The roll-to-roll dry coating process is a promising method for fabricating high-energy density, low-cost Li-ion batteries. Compared to conventional wet processing, it reduces manufacturing time and cost and offers environmental benefits by avoiding toxic solvents. However, thick dry electrodes increase charge transfer resistance (R_ct) and Li-ion migration resistance (R_ion) due to microstructural inhomogeneity. By systematically manipulating the variables of microstructural evolution, a high-thickness dry electrode with a homogeneous structure, featuring 1) uniform component distribution and 2) crack-free particles, could be achieved.

Keywords: Chemical mechanical planarization; nanoparticle; dispersion; Li-ion batteries; and roll-to-roll dry coating process.