Trimetallic Ru@AuPt core-shell nanostructures: The effect of microstrain on CO adsorption and electrocatalytic activity of formic acid oxidation

• Published in: Journal of colloid and interface science Vol. 570; pp. 72 - 79
• Main Authors: Hu, Xiao, Zou, Jiasui, Gao, Hongcheng, Kang, Xiongwu
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 15.06.2020
• Subjects: adsorption; carbon monoxide; catalysts; catalytic activity; Core-shell; Defect; Electrocatalysis; electrochemistry; energy; engineering; ethanol; formic acid; Formic acid oxidation; geometry; gold; Microstrain; nanoparticles; oxidation; platinum; ruthenium; transmission electron microscopy; X-ray diffraction; X-ray photoelectron spectroscopy; Electrocatalysis; Defect; Core-shell; Formic acid oxidation; Microstrain
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2020.02.111

The catalytic activity of Ru@Au-Pt core@shell nanoparticles demonstrates a linear dependence on the microstrain: black, dark red and blue dots represent Ru, Au and Pt atoms respectively. [Display omitted] •Ru@AuPt core-shell nanoparticles with varied Au/Pt ratio and AuPt shell thickness are prepared.•The more Au component resulted in more up-shift of the d-band.•An inverted volcano trend between the CO adsorption energy and the microstrain of metal nanoparticles is observed.•The catalytic activity displayed a linear dependence on the microstrain.•The best catalytic activity of Ru@AuPt catalyst is 52 times that of Pt/C. It is desirable to unravel the correlation between the geometric and electronic structures and the activity and further prepare high-performance electrocatalysts. Here in this paper, trimetallic Ru@Au-Pt core-shell nanoparticles were prepared by sequential ethanol reduction method, and further subject to characterization of X-ray diffraction, high angle annular dark field transmission electron microscopy, X-ray photoelectron spectroscopy and electrochemical CO stripping. Further analysis based on Williamson-Hall method revealed that the Au/Pt atomic ratio and shell thickness result in apparent variation of micro-strain and CO binding energy of Ru@AuPt nanoparticles, where the CO oxidation peak potential showed an inverted volcano-shape dependence on the microstrain of the metal nanoparticles while the catalytic activity towards electrooxidation of formic acid is linearly dependent on the micro-strain. The best Ru@Au-Pt catalyst delivers a specific activity of 4.14 mA cm−2, which is 52 times that of Pt/C, respectively. This study indicated that the microstrain and stacking fault of metal nanoparticles might be a good descriptor for the catalytic activity and may shed light the rational design, synthesis and surface engineering towards the high-performance electrocatalyst.