Yun, Young Hwa Choi, Jungwoo Park, Youngtae Park, Hyeongjung Doo, Gisu Kim, Minjoong Han, Sang Soo Park, Jong Hyeok Lee, Sechan Lee, Changsoo Cho, Hyun-Seok 2025-07-31T02:30:14Z 2025-07-31T02:30:14Z 2025-07-28 2025-11 1613-6810 https://pubs.kist.re.kr/handle/201004/152909 To realize a sustainable energy transition, water electrolysis-particularly proton exchange membrane water electrolysis (PEMWE)-holds significant promise. However, practical deployment is hindered by the cost and instability of the anode catalyst, IrO2. Recent studies indicate that tuning the Ir & horbar;O bond distance, via doping or composite formation, is key to enhancing the oxygen evolution reaction (OER) performance of IrO2-based electrocatalysts. Herein, a hybrid-phase Ti-incorporated IrO2 electrocatalyst is developed, exhibiting outstanding OER activity (298.8 mV at 100 mA cm-2) and stability over 25 h. This improvement originates from asymmetric interatomic interactions introduced by Ti, as revealed by combined experimental X-ray analyses and theoretical modeling. Ti incorporation induces tensile strain along the z-axis in IrO2 motifs, effectively reducing the average Ir & horbar;O bond distance and thereby enhancing OER activity. In situ X-ray absorption spectroscopy further confirms that at 1.5 V (vs. RHE), the elongated Ir & horbar;O bond facilitates & horbar;OOH* intermediate formation while suppressing Ir dissolution, contributing to superior stability. These findings underscore the critical role of Ir & horbar;O bond engineering in balancing activity and durability, offering strategic insights for the rational design of high-performance OER catalysts for renewable energy technologies. English Wiley - V C H Verlag GmbbH & Co. Optimizing Hybrid-phase IrO2 Catalysts with Ti for Enhanced Oxygen Evolution Reaction for Proton Exchange Membrane Water Electrolysis Article 10.1002/smll.202503601 1 Small, v.21, no.44 Small 21 44 Y scie scopus 001521436200001 2-s2.0-105011077356 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article ELECTROCATALYST IRO2-TIO2 DISSOLUTION HIGH-SURFACE-AREA IRIDIUM OXIDES oxygen evolution dissolution mechanism in situ XAS IrO2 OER stability