title: Enhancing the performance of catalytic AuPt nanoparticles in nonaqueous lithium-oxygen batteries.
abstract: The deposition of catalytic AuPt (1 : 1) nanoparticles (NPs) into hollow mesoporous nitrogen-doped carbon microspheres (HMCMS) was found to significantly improve the effectiveness of the catalysis of oxygen reactions in nonaqueous lithium-oxygen batteries (LOBs); surpassing the performance of unsupported AuPt NPs or HMCMS in discharge and charge overpotentials (lower), specific capacity and rate performance (higher), and cycle life (longer). Specifically at a typical current density of 100 mA g(-1), a LOB with the AuPt/HMCMS cathode catalyst could provide discharge and charge capacities of 6028 and 6000 mA h g(-1) respectively and a charge-discharge voltage gap of only 1.27 V. The discharge capacity decreased by 5% when the current density was doubled, and by 23% when the current density was quintupled. The AuPt/HMCMS LOB could be cycled 75 times for a depth of discharge (DOD) of 1000 mA h g(-1) without exceeding the charge cut-off voltage of 4.4 V. These measurements indicate that the HMCMS is an outstanding catalyst support to use for increasing the effectiveness of oxygen electrocatalysts in the LOBs.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore. cheleejy@nus.edu.sg.
authors.forename: Meihua
authors.initials: M
authors.lastname: Lu
authors.forename: Dongyun
authors.initials: D
authors.lastname: Chen
authors.forename: Chaohe
authors.initials: C
authors.lastname: Xu
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhan
authors.forename: Jim Yang
authors.initials: JY
authors.lastname: Lee