Composition dependent activity of PdAgNi alloy catalysts for formic acid electrooxidation


Ulaş B., Çağlar A., Sahin O., Kivrak H.

JOURNAL OF COLLOID AND INTERFACE SCIENCE, vol.532, pp.47-57, 2018 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 532
  • Publication Date: 2018
  • Doi Number: 10.1016/j.jcis.2018.07.120
  • Journal Name: JOURNAL OF COLLOID AND INTERFACE SCIENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.47-57
  • Keywords: Pd, Ag, Ni, PdAgNi, Alloy, Electronic state, Formic acid electrooxidation, Impedance, PD CATALYSTS, ENHANCED ACTIVITY, PROMOTED PD, ELECTROCATALYST, NANOPARTICLES, EFFICIENT, AG, PERFORMANCE, CO, NANOTUBES
  • Van Yüzüncü Yıl University Affiliated: Yes

Abstract

In the present study, the carbon supported Pd, PdAg and PdAgNi (Pd/C, PdAg/C and PdAgNi/C) electrocatalysts are prepared via NaBH4 reduction method at varying molar atomic ratio for formic acid electrooxidation. These as-prepared electrocatalysts are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma mass spectrometry (ICP-MS), N-2 adsorption desorption, and X-ray electron spectroscopy (XPS), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), chronoamperometry (CA), and lineer sweep voltammetry (LSV). While Pd-50,Ag-50/C exhibits the highest catalytic activity among the bimetallic electrocatalyst, it is observed that Pd70Ag20Ni10/C electrocatalysts have the best performance among the all electrocatalysts. Its maximum current density is about 1.92 times higher than that of Pd/C (0.675 mA cm(-2)). Also, electrochemical impedance spectroscopy (EIS), chronoamperometry (CA) and lineer sweep voltammetry (LSV) results are in a good agreement with CV results in terms of stability and electrocatalytic activity of Pd50Ag50/C and Pd70Ag20Ni10/C. The Pd70Ag20Ni10/C catalyst is believed to be a promising anode catalyst for the direct formic acid fuel cell. (C) 2018 Elsevier Inc. All rights reserved.