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 (Peer-Reviewed Journal) 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, 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

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.