We report a robust method for effectively removing the chemisorbed Br−ions, a capping agent, from the surface of Pd nanocubes to maximize their catalytic activity. The Br−ions can be removed by simply heating the sample in water, but the desorption of Br−ions will expose the underneath Pd atoms to the O2from air for the formation of a relatively thick oxide layer. During potential cycling, the oxide layer evolves into detrimental features such as steps and terraces. By introducing a trace amount of hydrazine into the system, the Br−ions can be removed by heating without forming a thick oxide layer. The as‐cleaned nanocubes show greatly enhanced activity toward formic acid oxidation. This cleaning method can also remove Br−ions from Rh nanocubes and it is expected to work for other combinations of nanocrystals and capping agents.
We report a robust method for effectively removing the chemisorbed Br−ions, a capping agent, from the surface of Pd nanocubes to maximize their catalytic activity. The Br−ions can be removed by simply heating the sample in water, but the desorption of Br−ions will expose the underneath Pd atoms to the O2from air for the formation of a relatively thick oxide layer. During potential cycling, the oxide layer evolves into detrimental features such as steps and terraces. By introducing a trace amount of hydrazine into the system, the Br−ions can be removed by heating without forming a thick oxide layer. The as‐cleaned nanocubes show greatly enhanced activity toward formic acid oxidation. This cleaning method can also remove Br−ions from Rh nanocubes and it is expected to work for other combinations of nanocrystals and capping agents.
more » « less- Award ID(s):
- 1804970
- PAR ID:
- 10237066
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 59
- Issue:
- 43
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 19129-19135
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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