연구성과

금주의우수논문

SCI-E Article; Early Access
Tailored Electronic Structure of Ir in High Entropy Alloy for Highly Active and Durable Bifunctional Electrocatalyst for Water Splitting under an Acidic Environment
백운규
  1. 성명백운규()
  2. 소속공과대학 에너지공학과
  3. 캠퍼스
  4. 우수선정주2023년 06월 1째주
Author
Kwon, Jiseok (Dept Energy Engn); Sun, Seho (Dept Energy Engn); Choi, Seunggun (Dept Energy Engn); Jo, Seonghan (Dept Energy Engn); Park, Keemin (Dept Energy Engn); 박호범 (Dept Energy Engn); 백운규 (Dept Energy Engn); 송태섭 (Dept Energy Engn);
Corresponding Author Info
Paik, U; Song, TS (corresponding author), Hanyang Univ, Dept Energy Engn, Seoul 04763, South Korea.; Han, H (corresponding author), Konkuk Univ, Dept Energy Engn, 120 Neungdongro, Seoul 05029, South Korea.
E-mail
upaik@hanyang.ac.kr
Document Type
Article; Early Access
Source
ADVANCED MATERIALS Volume: Issue: Pages:- Published:2023
External Information
http://dx.doi.org/10.1002/adma.202300091
Abstract
Proton-exchange-membrane water electrolysis (PEMWE) requires an efficient and durable bifunctional electrocatalyst for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, Ir-based electrocatalyst is designed using the high entropy alloy (HEA) platform of ZnNiCoIrX with two elements (X: Fe and Mn). A facile dealloying in the vacuum system enables the construction of a nanoporous structure with high crystallinity using Zn as a sacrificial element. Especially, Mn incorporation into HEAs tailors the electronic structure of the Ir site, resulting in the d-band center being far away from the Fermi level. Downshifting of the d-band center weakens the adsorption energy with reaction intermediates, which is beneficial for catalytic reactions. Despite low Ir content, ZnNiCoIrMn delivers only 50 mV overpotential for HER at -50 mA cm(-2) and 237 mV overpotential for the OER at 10 mA cm(-2). Furthermore, ZnNiCoIrMn shows almost constant voltage for the HER and OER for 100 h and a high stability number of 3.4 x 10(5) n(hydrogen) n(Ir)(-1) and 2.4 x 10(5) n(oxygen) n(Ir)(-1), demonstrating the exceptional durability of the HEA platform. The compositional engineering of ZnNiCoIrMn limits the diffusion of elements by high entropy effects and simultaneously tailors the electronic structure of active Ir sites, resulting in the modified cohesive and adsorption energies, all of which can suppress the dissolution of elements.
Web of Science Categories
Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter
Funding
National Research Foundation of Korea (NRF) - Korea government (MSIT) [2020M3E6A1046757, 2022R1A5A1032539]; Basic Science Research Program through the National Research Foundation of Korea (NRF) - Ministry of Science, ICT and Future Planning [2021R1A2C209
Language
English
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