Publications by authors named "Rock Kil Ko"

This study focuses on developing fuel cell power technology for charging superconducting coils using variable resistor. For this purpose, a variable resistor is fabricated, and experimental equipment is built to control the amount of current applied to the superconducting coil by fixing the amount of gas supplied to the fuel cell and adjusting its driving voltage. The current and magnetic flux densities increase and decrease depending on the variable resistor.

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Unlike planar photoelectrodes, bendable and malleable photoelectrodes extend their application to mechanical flexibility beyond conventional rigid structures, which have garnered new attention in the field of photoelectrochemical water splitting. A bendable metal (Hastelloy), which has both bendability and compatibility with various oxide layers, allows high-temperature processes for crystallization; therefore it is far superior as a substrate than a conventional flexible polymer. In this study, we fabricate bendable BiVO crystalline thin films on the metal substrates by employing template layers (SrRuO/SrTiO) to reduce the structural misfits between BiVO and the substrate.

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We examined the local structural and the interfacial properties of YBa2Cu3O(7-x) (YBCO)/ZnO nanorods on SrTiO3 (STO) substrates using various measurements. Vertically aligned ZnO nanorods were synthesized on STO substrates using a catalyst-free metal-organic chemical vapor deposition. YBCO films were deposited ex-situ on the ZnO nanorods/STO templates using a DC magnetron sputtering deposition.

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