Author: 공과대학 교학팀

Gaptronics: my journey towards zero-nanometer technologies

Gaptronics: my journey towards zero-nanometer technologies Dai-Sik Kim Centre for Angstrom Scale Electromagnetism and Quantum Photonics Institute, Department of Physics, Ulsan National University of Science and Technology, Ulsan 44919, Korea daisikkim@unist.ac.kr The ability to control the final few nanometers before two objects collide, often with picometer precision ultimately preventing...

Theoretical analysis on the chemical principles of atomic layer deposition processes

Theoretical Understanding on the Chemical Principles of Atomic Layer Deposition   Bonggeun Shong Chemical Engineering, Hongik University   Atomic layer deposition (ALD) is a vapor phase thin film deposition technique based on sequential, self-limiting surface reactions. Through ALD, exceptional conformality on high-aspect ratio structures, thickness control at the Angstrom level,...

Soft Interfaces: From Microfluidics to Kitchen

Abstract Living matter, from plants and animal cells, comprises complex materials with various phases and interfaces. A close look at how these soft interfaces arise and form certain shapes with functions will not only deepen our understanding of nature but also inspire the design and engineering of materials for novel applications. In this talk, I will first introduce hydrodynamic synchronization, which can be observed in swimming organisms, and explain how hydrodynamically interacting fluid-fluid interfaces can act as coupled oscillators leading to the discovery of a synchronized droplet generation. Second, I will present methods to fabricate nature-inspired shapes of microstructure to provide multifunctionality to the material, such as wrinkles on curved surfaces and multi-compartment microfibers, by exploiting oil-water interfaces. Lastly, I will investigate biological cells as soft matter to study the dependence of their motility on the geometry of cells and confinements as in complex tissue environments. We can even use materials found in our kitchen to understand the physicochemical roles of complex fluids in determining the shapes and motility of nature. My ultimate research goal in soft interfaces is to apply the knowledge from complex fluids experiments to emerging technologies of biomedical applications....

Novel Approaches for Emerging Rechargeable Batteries

Novel Approaches for Emerging Rechargeable Batteries   Jang Wook Choi (최장욱)   School of Chemical and Biological Engineering, Seoul National University, Republic of Korea   *e-mail address (jangwookchoi@snu.ac.kr)     Although Li-ion batteries have been successful in various applications, their shortcomings with regard to high cost and global maldistribution of raw materials, as well as safety concerns have promoted alternative rechargeable batteries based on other carrier ions represented by sodium and magnesium ions, targeting grid-scale energy storage systems (ESSs). However, many electrode materials in these emerging systems often suffer from sluggish kinetics due to the larger size or bivalency of carrier ions, limiting electrochemical performance particular in specific capacity and operation voltage. In this talk, I will introduce a new approach of engaging intercalated water in layered cathode materials. The intercalated water improves the performance of the given materials substantially by shielding electrostatic interactions or maintaining the crystal frameworks over repeated cycles. Detailed effects of intercalated water will also be described, along with promising potentials towards aqueous operations. I will also briefly introduce recent studies on zinc metal electrodes in light of managing surface side reactions including hydrogen evolution reaction (HER). ...