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Title: The Role of Citric Acid in Perfecting Platinum Monolayer on Palladium Nanoparticles during the Surface Limited Redox Replacement Reaction

Abstract

Cu-mediated-Pt-displacement method that involves the displacement of an underpotentially deposited (UPD) Cu monolayer by Pt has been extensively studied to prepare core-shell catalysts. It has been found that Pt clusters instead of a uniform Pt monolayer were formed in the gram batch synthesis. With a suitable surfactant, such as citric acid, the Pt shell could be much more uniform. In this study, the role of citric acid in controlling the Cu-Pt displacement reaction kinetics was studied by electrochemical techniques and theoretical approaches. It was found that citric acid strongly adsorbed on Pd, Pt, Cu/Pd, and Pt/Pd surfaces, especially in the double layer region in acid solutions. The strong adsorption of citric acid slowed down the Cu-Pt displacement reaction. The main characteristics of such strong interaction most likely arises from the OH groups in the citric acid molecule according to the molecular dynamics simulation results.

Authors:
 [1];  [1];  [1];  [2];  [3];  [3];  [4];  [5];  [1]
  1. Hong Kong Univ. of Science & Technology, Kowloon (Hong Kong). Dept. of Chemical and Biomolecular Engineering
  2. Chongqing Univ. (China). College of Chemistry and Chemical Engineering
  3. Brookhaven National Lab. (BNL), Upton, NY (United States). Dept. of Chemistry
  4. Univ. of Houston, TX (United States). Dept. of Electrical and Computer Engineering
  5. National Supercomputing Center in Shenzhen, Guangdong (China)
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1348291
Report Number(s):
BNL-113672-2017-JA
Journal ID: ISSN 0013-4651; R&D Project: MA510MAEA; KC0302010
Grant/Contract Number:
SC0012704; AC02-98CH10886; 0955922
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of the Electrochemical Society
Additional Journal Information:
Journal Volume: 163; Journal Issue: 12; Journal ID: ISSN 0013-4651
Publisher:
The Electrochemical Society
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Core-shell; density functional theory; fuel cells; monolayer; surfactant

Citation Formats

Zhu, Shangqian, Yue, Jeffrey, Qin, Xueping, Wei, Zidong, Liang, Zhixiu, Adzic, Radoslav R., Brankovic, Stanko R., Du, Zheng, and Shao, Minhua. The Role of Citric Acid in Perfecting Platinum Monolayer on Palladium Nanoparticles during the Surface Limited Redox Replacement Reaction. United States: N. p., 2016. Web. doi:10.1149/2.0061612jes.
Zhu, Shangqian, Yue, Jeffrey, Qin, Xueping, Wei, Zidong, Liang, Zhixiu, Adzic, Radoslav R., Brankovic, Stanko R., Du, Zheng, & Shao, Minhua. The Role of Citric Acid in Perfecting Platinum Monolayer on Palladium Nanoparticles during the Surface Limited Redox Replacement Reaction. United States. doi:10.1149/2.0061612jes.
Zhu, Shangqian, Yue, Jeffrey, Qin, Xueping, Wei, Zidong, Liang, Zhixiu, Adzic, Radoslav R., Brankovic, Stanko R., Du, Zheng, and Shao, Minhua. 2016. "The Role of Citric Acid in Perfecting Platinum Monolayer on Palladium Nanoparticles during the Surface Limited Redox Replacement Reaction". United States. doi:10.1149/2.0061612jes. https://www.osti.gov/servlets/purl/1348291.
@article{osti_1348291,
title = {The Role of Citric Acid in Perfecting Platinum Monolayer on Palladium Nanoparticles during the Surface Limited Redox Replacement Reaction},
author = {Zhu, Shangqian and Yue, Jeffrey and Qin, Xueping and Wei, Zidong and Liang, Zhixiu and Adzic, Radoslav R. and Brankovic, Stanko R. and Du, Zheng and Shao, Minhua},
abstractNote = {Cu-mediated-Pt-displacement method that involves the displacement of an underpotentially deposited (UPD) Cu monolayer by Pt has been extensively studied to prepare core-shell catalysts. It has been found that Pt clusters instead of a uniform Pt monolayer were formed in the gram batch synthesis. With a suitable surfactant, such as citric acid, the Pt shell could be much more uniform. In this study, the role of citric acid in controlling the Cu-Pt displacement reaction kinetics was studied by electrochemical techniques and theoretical approaches. It was found that citric acid strongly adsorbed on Pd, Pt, Cu/Pd, and Pt/Pd surfaces, especially in the double layer region in acid solutions. The strong adsorption of citric acid slowed down the Cu-Pt displacement reaction. The main characteristics of such strong interaction most likely arises from the OH groups in the citric acid molecule according to the molecular dynamics simulation results.},
doi = {10.1149/2.0061612jes},
journal = {Journal of the Electrochemical Society},
number = 12,
volume = 163,
place = {United States},
year = 2016,
month = 7
}

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