title: Improved reversibility in lithium-oxygen battery: understanding elementary reactions and surface charge engineering of metal alloy catalyst.
abstract: Most Li-O2 batteries suffer from sluggish kinetics during oxygen evolution reactions (OERs). To overcome this drawback, we take the lesson from other catalysis researches that showed improved catalytic activities by employing metal alloy catalysts. Such research effort has led us to find Pt3Co nanoparticles as an effective OER catalyst in Li-O2 batteries. The superior catalytic activity was reflected in the substantially decreased overpotentials and improved cycling/rate performance compared to those of other catalysts. Density functional theory calculations suggested that the low OER overpotentials are associated with the reduced adsorption strength of LiO2 on the outermost Pt catalytic sites. Also, the alloy catalyst generates amorphous Li2O2 conformally coated around the catalyst and thus facilitates easier decomposition and higher reversibility. This investigation conveys an important message that understanding elementary reactions and surface charge engineering of air-catalysts are one of the most effective approaches in resolving the chronic sluggish charging kinetics in Li-O2 batteries.
authors.affiliation: 1] Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea [2].
authors.forename: Byung Gon
authors.initials: BG
authors.lastname: Kim
authors.affiliation: 1] Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul, 100-715, Republic of Korea [2].
authors.forename: Hyung-Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Seoin
authors.initials: S
authors.lastname: Back
authors.affiliation: Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Kwan Woo
authors.initials: KW
authors.lastname: Nam
authors.affiliation: 1] Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea [2] KAIST Institute NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Yousung
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul, 100-715, Republic of Korea.
authors.forename: Young-Kyu
authors.initials: YK
authors.lastname: Han
authors.affiliation: 1] Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea [2] KAIST Institute NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Jang Wook
authors.initials: JW
authors.lastname: Choi