Electronic Ensemble Effects of Organic/Inorganic Hybrid Surface on PtCo Nanoparticles for Oxygen Reduction Reactions

Title
Electronic Ensemble Effects of Organic/Inorganic Hybrid Surface on PtCo Nanoparticles for Oxygen Reduction Reactions
Authors
정남기Satadeep BhattacharjeeSanjeev Gautam박희영류재윤정영훈이상영장인준장종현박세흠정동영성영은채근화Umesh V Waghmare이승철유성종
Keywords
연료전지; 합금촉매; 산소환원반응; PtCo; PNIPAM
Issue Date
2016-02
Publisher
NPG asia materials
Citation
VOL 8, 237
Abstract
In Pt-transition metal (TM) alloy catalysts, the electron transfer from the TM to Pt is retarded owing to the inevitable oxidation of the TM surface by oxygen. In addition, acidic electrolytes such as those employed in fuel cells accelerate the dissolution of the surface TM oxide, which leads to catalyst degradation. Herein, we propose a novel synthesis strategy that selectively modifies the electronic structure of surface Co atoms with N-containing polymers, resulting in highly active and durable PtCo nanoparticle catalysts useful for the oxygen reduction reaction (ORR). The polymer, which is functionalized on carbon black, selectively interacts with the Co precursor, resulting in Co–N bond formation on the PtCo nanoparticle surface. Electron transfer from Co to Pt in the PtCo nanoparticles modified by the polymer is enhanced by the increase in the difference in electronegativity between Pt and Co compared with that in bare PtCo nanoparticles with the TM surface oxides. In addition, the dissolution of Co and Pt is prevented by the selective passivation of surface Co atoms and the decrease in the O-binding energy of surface Pt atoms. As a result, the catalytic activity and durability of PtCo nanoparticles for the ORR are significantly improved by the electronic ensemble effects. The proposed organic/inorganic hybrid concept will provide new insights into the tuning of nanomaterials consisting of heterogeneous metallic elements for various electrochemical and chemical applications.
URI
http://pubs.kist.re.kr/handle/201004/58523
ISSN
18844049
Appears in Collections:
KIST Publication > Article
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE