Do Hyun Kim

By Leian Bartolome, Muhammad Imran, Bong Gyoo Cho, Waheed A. Al-Masry and Do Hyun Kim

Part of the book: Material Recycling

By Kwangseok Seo, Minyoung Kim and Do Hyun Kim

Recently, Young’s equation, the Wenzel equation, and the Cassie-Baxter equation have been widely used with active research on superhydrophobic surfaces. However, experiments showed that the Wenzel equation and the Cassie-Baxter equation were not derived correctly. They should be reviewed on a firm physical ground. In this study, these equations are re-derived from a thermodynamic point of view by employing energy minimization and variational approach. The derivations provide a deeper understanding of these equations and the behavior of a contact angle. Also, in applying these equations, the limitations and considerations are discussed. It is expected that this study will provide a theoretical basis for the careful use of these equations on rough or chemically heterogeneous surfaces.

Part of the book: Surface Energy

By Arvin Sangalang, Seunghwan Seok and Do Hyun Kim

The recycling of chemicals and generation of alternative energy are central topics in the efforts toward sustainable development. Among these, research on plastics recycling and fuel cells has received significant attention, with the aim of designing novel catalysts to improve yield and efficiency. We highlight our work on these areas focusing on the chemical depolymerization of polyethylene terephthalate (PET) to recover its constituent monomer and the development of high-performance anode catalysts for polymer electrolyte membrane fuel cells (PEMFC). We demonstrate various flexible yet practical synthesis strategies (e.g. ultrasound-assisted deposition and biopolymer coating) that were used to obtain catalytic properties optimized for these applications. The effectiveness and simplicity of these methods render the catalysts to be truly green — from synthesis up to process application.

Part of the book: Advanced Catalytic Materials