Title: Enhancing Coating Material Performance: Elastic Properties and Strength of the Interface Bonding in (Ti0.875M0.125)N Solid solution                                                                                                                                                                                                                      김효경 학생은 고경도 난삭재용 박막을 개발하기 위해 HT-DFT를 이용하여 고경도 박막을 설계하였고, 해당 박막의 밀착력을 분석하였습니다. 해당 주제로 발표하였습니다.

Title: Predicting Thermal Expansion Properties of Complex Composite Materials Using Multi-scale Simulation

Title: Development of coatings with improved thermal stability through functionally graded coating material design                   김효경 학생은 열팽창계수에 의한 박막 박리 현상을 해결하기 위한 HT-DFT를 이용한 조성 설계를 주제로 발표하였습니다. 

Author: J. Kim†, M. Kim†,  H. Kim, S. Park, and J. Kim*Title: Insights into the ultra-high temperature solid solutions Hf-Ta-C-N quaternary system using high-throughput calculationJournal: Journal of Materials Research and Technology-JMR&TYear: 2023Impact factor: 6.267Abstract:We investigated the structure, elastic, and thermodynamic properties of Hf-Ta-C-N solid solutions using high-throughput density functional theory calculations. The results of the elastic and mechanical properties indicate that increasing the nitrogen content increases the ductility of solid solutions; it also increases the elastic moduli of solid solutions in a specific range of nitrogen contents. The results indicate that the ternary and quaternary solid solutions of the Hf-Ta-C-N system have excellent formability, elastic, and thermal properties. In addition, thermodynamic analyses were performed to obtain temperature-dependent stable phase diagrams of the Hf-Ta-C-N quaternary system. This investigation was performed to determine the suitability of Hf-Ta-C-N quaternary solid solutions in high temperature condition, which was veiled in previous studies. In total, 51 related phases were studied, including 16 solid solutions and four elemental phases (Hf, Ta, C, and N2(g)). Our results indicate that the nitrogen-rich solid solutions can appear even at room temperature. The solid solutions covered a large area of the Hf-Ta-C-N phase spaces, regardless of temperature. As the temperature increases, the stable phase shifts from Ta and N to the Hf and C rich phases.

Author: D. Park†, M. Kim, M. Kim, J. Byeon, J. Jang, J. Kim, D. Lim, S. Park, Y. Gu, J. Kim*, K. Park*Title: Spherical nickel doped cobalt phosphide as an anode catalyst for oxygen evolution reaction in alkaline media: From catalysis to systemJournal: Applied Catalysis B: ENVIRONMENTALYear: 2023Impact factor: 24.319Abstract:Anion exchange membrane water electrolysis (AEMWE) uses a zero-gap membrane-electrode-assembly (MEA) consisting of a polymer electrolyte membrane and non-precious metal-based catalysts. However, anode catalysts for the oxygen evolution reaction (OER), which is the rate-determining-step in WE, need to be intensively developed to achieve superior electrocatalytic activity and stability. Herein, we report the synthesis and characterization (experimental and simulation) of spherical Ni-doped (5–15 at%) cobalt phosphide (Ni-CoP) as the anode catalyst for the OER. Specifically, the DFT calculation exhibited that the addition of Ni in CoP might increase the energy density in the Fermi level of pristine CoP, enhance the charge transfer rate during the OER, and reduce the energy barrier for the formation of OOH* , thereby boosting the OER activity. The prepared Ni-doped CoP catalyst was directly loaded onto a foam-type Ni-based gas diffusion layer for effective application in AEMWE. It was found that the electrocatalytic activity of the AEMWE depends on the porosity of the NFs as catalyst substrates. The unit cell containing the membrane-electrode-assembly fabricated with NCP-10 delivered a high current density of 1.12 A cm−2 at 1.8 V and a low reduction rate of 0.64 mA cm−2 h−1 for 250 h.