Premium
Simple Electrodeposition of Dendritic Pd Without Supporting Electrolyte and Its Electrocatalytic Activity Toward Oxygen Reduction and H 2 O 2 Sensing
Author(s) -
Kang Minkyung,
Yang Yejin,
Shim Jun Ho,
Lee Sang Cheol,
Lee Youngmi,
Lee Chongmok
Publication year - 2013
Publication title -
electroanalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.574
H-Index - 128
eISSN - 1521-4109
pISSN - 1040-0397
DOI - 10.1002/elan.201300399
Subject(s) - overpotential , catalysis , palladium , electrocatalyst , inorganic chemistry , electrolyte , electrochemistry , hydrogen peroxide , metal , chemistry , substrate (aquarium) , aqueous solution , amperometry , materials science , electrode , organic chemistry , oceanography , geology
Metallic palladium (Pd) electrocatalysts for oxygen reduction and hydrogen peroxide (H 2 O 2 ) oxidation/reduction are prepared via electroplating on a gold metal substrate from dilute (5 to 50 mM) aqueous K 2 PdCl 4 solution. The best Pd catalyst layer possessing dendritic nanostructures is formed on the Au substrate surface from 50 mM Pd precursor solution (denoted as Pd‐50) without any additional salt, acid or Pd templating chemical species. The Pd‐50 consisted of nanostructured dendrites of polycrystalline Pd metal and micropores within the dendrites which provide high catalyst surface area and further facilitate reactant mass transport to the catalyst surface. The electrocatalytic activity of Pd‐50 proved to be better than that of a commercial Pt (Pt/C) in terms of lower overpotential for the onset and half‐wave potentials and a greater number of electrons ( n ) transferred. Furthermore, amperometric i – t curves of Pd‐50 for H 2 O 2 electrochemical reaction show high sensitivities (822.2 and −851.9 µA mM −1 cm −2 ) and low detection limits (1.1 and 7.91 µM) based on H 2 O 2 oxidation H 2 O 2 reduction, respectively, along with a fast response (<1 s).