Jeong, Yo Sub Park, Jin-Bum Jung, Hun-Gi Kirn, Jooho Luo, Xiangyi Lu, Jun Curtiss, Larry Amine, Khalil Sun, Yang-Kook Scrosati, Bruno Lee, Yun Jung 2024-01-20T07:00:19Z 2024-01-20T07:00:19Z 2021-08-31 2015-07 1530-6984 https://pubs.kist.re.kr/handle/201004/125317 Among many challenges present in Li-air batteries, one of the main reasons of low efficiency is the high charge overpotential due to the slow oxygen evolution reaction (OER). Here, we present systematic evaluation of Pt, Pd, and Ru nanopartides supported on rGO as OER electrocatalysts in Li-air cell cathodes with LiCF3SO3-tetra(ethylene glycol) dimethyl ether (TEGDME) salt-electrolyte system. All of the noble metals explored could lower the charge overpotentials, and among them, Ru-rGO hybrids exhibited the most stable cycling performance and the lowest charge overpotentials. Role of Ru nanopartides in boosting oxidation kinetics of the discharge products were investigated. Apparent behavior of Ru nanoparticles was different from the conventional electrocatalysts that lower activation barrier through electron transfer, because the major contribution of Ru nanopartides in lowering charge overpotential is to control the nature of the discharge products. Ru nanopartides facilitated thin film-like or nanoparticulate Li2O2 formation during oxygen reduction reaction (ORR), which decomposes at lower potentials during charge, although the conventional role as electrocatalysts during OER cannot be ruled out. Pt-and Pd-rGO hybrids showed fluctuating potential profiles during the cycling. Although Pt- and Pd-rGO decomposed the electrolyte after electrochemical cycling, no electrolyte instability was observed with Ru-rGO hybrids. This study provides the possibility of screening selective electrocatalysts for Li-air cells while maintaining electrolyte stability. English AMER CHEMICAL SOC ELECTROCATALYTIC ACTIVITY PLATINUM NANOPARTICLES LI-O-2 BATTERY REDUCTION OXIDATION METHANOL LI2O2 DISPROPORTIONATION MORPHOLOGY DISCHARGE Study on the Catalytic Activity of Noble Metal Nanoparticles on Reduced Graphene Oxide for Oxygen Evolution Reactions in Lithium-Air Batteries Article 10.1021/nl504425h 1 NANO LETTERS, v.15, no.7, pp.4261 - 4268 NANO LETTERS 15 7 4261 4268 scie scopus 000357964100004 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article ELECTROCATALYTIC ACTIVITY PLATINUM NANOPARTICLES LI-O-2 BATTERY REDUCTION OXIDATION METHANOL LI2O2 DISPROPORTIONATION MORPHOLOGY DISCHARGE lithium-air batteries catalysts noble metals electrolyte stability catalytic mechanism