Korea Naval Academy

About: Korea Naval Academy is a education organization based out in Changwon, South Korea. It is known for research contribution in the topics: Catalysis & Proton exchange membrane fuel cell. The organization has 65 authors who have published 121 publications receiving 1538 citations. The organization is also known as: Republic of Korea Naval Academy.

Poly(carbazole)-based anion-conducting materials with high performance and durability for energy conversion devices

Abstract: Anion conducting polymers (ACPs) are essential materials for alkaline electrochemical energy technology such as anion-exchange membrane fuel cells (AEMFCs) and water electrolysers (AEMWEs). The aforementioned polymers are promising alternatives for proton exchange membrane-based systems due to the possibility of using platinum group metal-free electrocatalysts. However, there are still no reliable ACPs possessing the desired performance and stability, which is a major challenge for developing alkaline energy systems. Herein, we highlight an anion-exchange membrane and ionomer based on quaternised poly-carbazole (QPC-TMA) with a rigid ether-free and curved backbone structure comprised of carbazole monomers. The developed ACP exhibits excellent ionic conductivity, as well as chemical and mechanical stability. Moreover, the AEMFC using QPC-TMA shows excellent performance (1.61 W cm−2) compared with the other best-performing AEMFCs. In addition, the AEMWE using QPC-TMA demonstrates outstanding stability and state-of-the-art performance (3.5 A cm−2 at 1.9 V), which is the first report of an AEMWE that outperforms the best-performing proton-exchange membrane water electrolysers.

Soft-template synthesis of mesoporous non-precious metal catalyst with Fe-N-X/C active sites for oxygen reduction reaction in fuel cells

Abstract: We synthesized ordered mesoporous Fe/N/C with highly active Fe-N x /C sites denoted as m-FePhen-C as a non-precious metal catalyst (NPMC) for the oxygen reduction reaction in fuel cells. This was the first study that incorporated a catalyst precursor with Fe-N coordination directly in a simple block co-polymer-assisted soft-template method for the synthesis of mesoporous Fe/N/C. The synthesized catalyst (m-FePhen-C) showed a high catalytic performance comparable to that of Pt/C in half-cell tests, and a membrane electrode assembly (MEA) with an m-FePhen-C cathode exhibited 40% higher power density than did an MEA with a commercial Pt/C cathode in single-cell tests, with comparable electrode thicknesses. This result is highly meaningful in that generation of the Fe-N x /C active sites and formation of ordered mesoporous structure were achieved simultaneously in the simple soft-template-assisted process, and in that the advantages of mesoporous structure with appropriate pore size in metal-containing NPMC were elucidated for high-performance MEAs.

Biomass-Derived Air Cathode Materials: Pore-Controlled S,N-Co-doped Carbon for Fuel Cells and Metal–Air Batteries

Abstract: An earth-abundant and feasible air cathode electrocatalyst is of importance for energy devices including fuel cells and metal–air batteries. Herein, hierarchically porous S,N-co-doped carbon materi...

An optimal layout of container yards

Abstract: This study presents a method for designing the layout of container yards where transfer cranes and yard trucks are used for stacking containers in the yard and delivering them between the yard and the quay. A method to determine the layout type, the outline of the yard, and the numbers of vertical and horizontal aisles is suggested. For estimating the effects of the design variables on operational cost terms, formulas for estimating the number of relocations by yard cranes and the expected travel distance of trucks are derived. Numerical examples are provided to illustrate the design procedure. It was also shown that the layout in which blocks are laid out parallel to the side with the gate or the quay outperforms that in which blocks are laid out perpendicular to the side with the gate or the quay.