High-indexed Pt₃Ni alloy tetrahexahedral nanoframes evolved through preferential CO etching

Journal Article · Tue Mar 07 00:00:00 EST 2017 · Nano Letters

DOI:https://doi.org/10.1021/acs.nanolett.6b04731· OSTI ID:1368669

Wang, Chenyu ^[1]; Zhang, Lihua ^[2]; Yang, Hongzhou ^[3]; Pan, Jinfong ^[1]; Liu, Jingyue ^[4]; Dotse, Charles ^[3]; Luan, Yiliang ^[1]; Gao, Rui ^[5]; Lin, Cuikun ^[6]; Zhang, Jun ^[7]; Kilcrease, James P. ^[8]; Wen, Xiaodong ^[5]; Zou, Shouzhong ^[9]; Fang, Jiye  ^[1]

---

1. State Univ. of New York at Binghamton, Binghamton, NY (United States)
2. Brookhaven National Lab. (BNL), Upton, NY (United States)
3. Miami Univ., Oxford, OH (United States)
4. Arizona State Univ., Tempe, AZ (United States)
5. Chinese Academy of Sciences, Shanxi (China); Synfuels China Co. Ltd., Beijing (China)
6. Univ. of South Dakota, Vermillion, SD (United States)
7. China Univ. of Petroleum, Shandong (China)
8. Hitachi High Technologies America, Inc., Clarksburg, MD (United States)
9. Miami Univ., Oxford, OH (United States); American Univ., Washington, D.C. (United States)

Here, chemically controlling crystal structures in nanoscale is challenging, yet provides an effective way to improve catalytic performances. Pt-based nanoframes are a new class of nanomaterials that have great potential as high-performance catalysts. To date, these nanoframes are formed through acid etching in aqueous solutions, which demands long reaction time and often yields ill-defined surface structures. Herein we demonstrate a robust and unprecedented protocol for facile development of high-performance nanoframe catalysts using size and crystallographic facet-controlled PtNi₄ tetrahexahedral nanocrystals prepared through a colloidal synthesis approach as precursors. This new protocol employs the Mond process to preferentially dealloy nickel component in the <100> direction through carbon monoxide etching of carbon-supported PtNi₄ tetrahexahedral nanocrystals at an elevated temperature. The resultant Pt₃Ni alloy tetrahexahedral nanoframes possess an open, stable, and high-indexed microstructure, containing a segregated Pt thin layer strained to the Pt–Ni alloy surfaces and featuring a down-shift d-band center as revealed by the density functional theory calculations. These nanoframes exhibit much improved catalytic performance, such as high stability under prolonged electrochemical potential cycles, promoting direct electro-oxidation of formic acid to carbon dioxide and enhancing oxygen reduction reaction activities. Because carbon monoxide can be generated from the carbon support through thermal annealing in air, a common process for pretreating supported catalysts, the developed approach can be easily adopted for preparing industrial scale catalysts that are made of Pt–Ni and other alloy nanoframes.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC00112704
• OSTI ID: 1368669
• Report Number(s): BNL-113996-2017-JA; R&D Project: 16060; 16060; KC0403020
• Journal Information: Nano Letters, Vol. 17, Issue 4; ISSN 1530-6984
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
nanoframe
tetrahexahedron
high-index
preferential etching
Pt3Ni
Center for Functional Nanomaterials