title: Surface and interface engineering of FePt/C nanocatalysts for electro-catalytic methanol oxidation: enhanced activity and durability.
abstract: A methodology by coupling a microfluidic-batch process with in situ carbon-black mixing, successive annealing and de-alloying post-treatment was developed for engineering surface and interface microstructures of FePt/C nanocomposites. Ultra-small angular FePt nanocrystals rich in vertexes/terraces/steps and with Pt contents gradually increasing from the inner to the outer part can be synthesized at certain Fe/Pt atomic ratios (2/1 or 1.1/1), which can directly grow on carbon-black for enhanced nanocrystal-carbon interface interaction by introducing the in situ carbon-black mixing process. Composition and structure characterization suggests that FePt@(Fe1-xPtx)Oy(OH)z/C nanocomposites with FePt alloy cores and surface Pt-doping hydroxyl iron oxide shells are formed after annealing. After controlled de-alloying of Fe in annealed nanocrystals with a Fe/Pt ratio of 2/1, the finally formed nanocatalysts exhibited excellent electrochemical catalytic performance using the methanol oxidation reaction as a model, preserving an activity of 1610 mA mg-1Pt-1(12 times the commercial Pt/C catalysts, higher than the best result (7.9 times the commercial Pt/C catalysts) just published in Science (Science, 2016, 354, 1410-1414), enhanced durability and high tolerance to CO poisoning.
authors.affiliation: Center for Modern Physics Technology and Applied Physics Department, School of Mathematics and Physics, University of Science & Technology Beijing, Beijing 100083, China. songyj@ustb.edu.cn.
authors.forename: Junmei
authors.initials: J
authors.lastname: Wang
authors.affiliation: School of Physics and Nucleation Engineering, Beihang University, Beijing 100191, China.
authors.forename: Zhenlei
authors.initials: Z
authors.lastname: Wang
authors.affiliation: School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Li
authors.affiliation: Center for Modern Physics Technology and Applied Physics Department, School of Mathematics and Physics, University of Science & Technology Beijing, Beijing 100083, China. songyj@ustb.edu.cn.
authors.forename: Rongming
authors.identifier: http://orcid.org/0000-0003-4075-6956
authors.initials: R
authors.lastname: Wang
authors.affiliation: Center for Modern Physics Technology and Applied Physics Department, School of Mathematics and Physics, University of Science & Technology Beijing, Beijing 100083, China. songyj@ustb.edu.cn.
authors.forename: Yujun
authors.identifier: http://orcid.org/0000-0003-2474-084X
authors.initials: Y
authors.lastname: Song