Surface voltammetric dealloying investigation on PdCu/C electrocatalysts toward ethanol oxidation in alkaline media

  • Chan Zhu
  • Yao-Yue YangEmail author
  • Zhi-Gang Zhao
Research Paper


Voltammetric dealloying is employed here to investigate the correlations between catalytic performance and surface composition and structure, taking ethanol oxidation reaction (EOR) on Pd-Cu alloy surface as a case study. First, home-made PdCu/C with a mean particle size of ca. 3.11 ± 0.6 nm is dealloyed by repetitive potential cycling in 0.5 M H2SO4. With dealloying cycles rising, the Cu component is gradually leached out and the corresponding Pd/Cu atomic ratio gradually increases from ca. 2.1 to 4.0; meanwhile, SEM images display that Pd-rich porous shell is formed due to dealloying-induced surface structural rearrangement, being verified by the appearance of ear-like peaks at − 0.015 V (vs. SCE) in CVs collected in 0.5 M H2SO4; furthermore, XPS spectra indicate that core-level binding energies of Pd 3d5/2 first positively shift to 336.1 eV and then oppositively move down to 334.9 eV, indicating that the d-band center of Pd composition is modulated by the dealloying treatment. Moreover, the voltammetric peak current densities for EOR follow the order of PdCu/C-DA15 > as-prepared PdCu/C ˃ > PdCu/C-DA30 ˃ commercial Pd/C ˃ PdCu/C-DA75, due to the modest downshift of Pd d-band center resulted by charge transfer and surface atomic rearrangement. In addition, the EOR durability gradually decays with the continuous loss of Cu, indicating that electro-oxidation of surface species also follows the so-called bi-functional mechanism. This work might provide some new insights into the catalysis enhancement by tuning the surface/interfacial structure of catalysts.

Graphical abstract

The voltammetric peak current densities for ethanol oxidation on home-made PdCu/C catalysts gradually decrease with the dealloying cycles rising, suggesting that the surface voltammetric dealloyment could effectively modulate the surface composition and structure, so as to tune the catalytic performance.


PdCu dealloyment Ethanol oxidation Surface reconstruction Electronic effects Bi-functional mechanism Nanoscale surface phenomena 


Funding information

This work was supported by NSFC (grant numbers 21603177), Natural Science Foundation of Sichuan Province (grant numbers 2016JY0212), and the Fundamental Research Funds for the Central Universities (grant numbers 2018NZD04). Chan Zhu is financially supported by SMU innovation programs for graduate students (CX2018SZ133).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

11051_2018_4423_MOESM1_ESM.docx (1.5 mb)
ESM 1 (DOCX 1543 kb)


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Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.College of Chemistry and Environmental Protection EngineeringSouthwest Minzu UniversityChengduChina

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