Abstract
This article reports a facile method for the synthesis of Pd-Ru nanocages by activating the galvanic replacement reaction between Pd nanocrystals and a Ru(III) precursor with I- ions. The as-synthesized nanocages feature a hollow interior, ultrathin wall of ≈2.5 nm in thickness, and a cubic shape. Our quantitative study suggests that the reduction rate of the Ru(III) precursor can be substantially accelerated upon the introduction of I- ions and then retarded as the ratio of I-/Ru3+ is increased. The Pd-Ru nanocages take an alloy structure, with the Ru atoms in the nanocages crystallized in a face-centered cubic structure instead of the hexagonal close-packed phase taken by bulk Ru. Using Pd nanocubes with different edge lengths, the dimensions of the nanocages in the range of 6−18 nm can readily be tuned. When tested as catalysts toward the electro-oxidation of ethylene glycol and glycerol, respectively, the Pd-Ru cubic nanocages prepared from 18 nm Pd cubes exhibit 5.1- and 6.2-fold enhancements in terms of mass activity relative to the commercial Pd/C. After 1000 cycles of accelerated durability test, the mass activities of the nanocages are still 3.3 and 3.7 times as high as that of the pristine commercial Pd/C catalyst, respectively.
Original language | English |
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Article number | 1900843 |
Journal | Small Methods |
Volume | 4 |
Issue number | 5 |
DOIs | |
State | Published - May 1 2020 |
Funding
This work was supported in part by the National Science Foundation (NSF) (CHE‐1804970) and startup funds from the Georgia Institute of Technology. XRD and electron microscope analyses were conducted at the Institute for Electronics and Nanotechnology (IEN, Georgia Institute of Technology), a member of the National Nanotechnology Coordinated Infrastructure, which is supported by the NSF (ECCS‐1542174). Part of the electron microscopy analyses was carried out in the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility (M.C. and Z.D.H.). Z.D.H. gratefully acknowledges support from the NSF Graduate Research Fellowship (DGE‐1650044) and the Georgia Tech‐ORNL Fellowship. This work was supported in part by the National Science Foundation (NSF) (CHE-1804970) and startup funds from the Georgia Institute of Technology. XRD and electron microscope analyses were conducted at the Institute for Electronics and Nanotechnology (IEN, Georgia Institute of Technology), a member of the National Nanotechnology Coordinated Infrastructure, which is supported by the NSF (ECCS-1542174). Part of the electron microscopy analyses was carried out in the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility (M.C. and Z.D.H.). Z.D.H. gratefully acknowledges support from the NSF Graduate Research Fellowship (DGE-1650044) and the Georgia Tech-ORNL Fellowship.
Keywords
- Pd-Ru nanocages
- electrocatalysis
- face-centered cubic alloys
- galvanic replacements
- reduction kinetics