TY - JOUR
T1 - Pt-Based Icosahedral Nanocages
T2 - Using a Combination of {111} Facets, Twin Defects, and Ultrathin Walls to Greatly Enhance Their Activity toward Oxygen Reduction
AU - Wang, Xue
AU - Figueroa-Cosme, Legna
AU - Yang, Xuan
AU - Luo, Ming
AU - Liu, Jingyue
AU - Xie, Zhaoxiong
AU - Xia, Younan
N1 - Funding Information:
This work was supported in part by start-up funds from the Georgia Institute of Technology and a grant from the NSF (CHE 1505441). As visiting Ph.D. students, X.W. and M.L. also received partial support from the China Scholarship Council. J.L. acknowledges the support by Arizona State University and the use of facilities in the John M. Cowley Center for High-Resolution Electron Microscopy at Arizona State University.
PY - 2016/2/10
Y1 - 2016/2/10
N2 - Engineering the surface structure of noble-metal nanocrystals offers an effective route to the development of catalysts or electrocatalysts with greatly enhanced activity. Here, we report the synthesis of Pt-based icosahedral nanocages whose surface is enclosed by both {111} facets and twin boundaries while the wall thickness can be made as thin as six atomic layers. The nanocages are derived from Pd@Pt4.5L icosahedra by selectively etching away the Pd in the core. During etching, the multiply twinned structure can be fully retained whereas the Pt atoms in the wall reconstruct to eliminate the corrugated structure built in the original Pt shell. The Pt-based icosahedral nanocages show a specific activity of 3.50 mA cm-2 toward the oxygen reduction reaction, much greater than those of the Pt-based octahedral nanocages (1.98 mA cm-2) and a state-of-the-art commercial Pt/C catalyst (0.35 mA cm-2). After 5000 cycles of accelerated durability test, the mass activity of the Pt-based icosahedral nanocages drops from 1.28 to 0.76 A mg-1Pt, which is still about four times greater than that of the original Pt/C catalyst (0.19 A mg-1Pt).
AB - Engineering the surface structure of noble-metal nanocrystals offers an effective route to the development of catalysts or electrocatalysts with greatly enhanced activity. Here, we report the synthesis of Pt-based icosahedral nanocages whose surface is enclosed by both {111} facets and twin boundaries while the wall thickness can be made as thin as six atomic layers. The nanocages are derived from Pd@Pt4.5L icosahedra by selectively etching away the Pd in the core. During etching, the multiply twinned structure can be fully retained whereas the Pt atoms in the wall reconstruct to eliminate the corrugated structure built in the original Pt shell. The Pt-based icosahedral nanocages show a specific activity of 3.50 mA cm-2 toward the oxygen reduction reaction, much greater than those of the Pt-based octahedral nanocages (1.98 mA cm-2) and a state-of-the-art commercial Pt/C catalyst (0.35 mA cm-2). After 5000 cycles of accelerated durability test, the mass activity of the Pt-based icosahedral nanocages drops from 1.28 to 0.76 A mg-1Pt, which is still about four times greater than that of the original Pt/C catalyst (0.19 A mg-1Pt).
KW - Platinum-based catalyst
KW - icosahedral nanocage
KW - multiply twinned structure
KW - oxygen reduction reaction
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U2 - 10.1021/acs.nanolett.5b05140
DO - 10.1021/acs.nanolett.5b05140
M3 - Article
AN - SCOPUS:84958078484
SN - 1530-6984
VL - 16
SP - 1467
EP - 1471
JO - Nano Letters
JF - Nano Letters
IS - 2
ER -