Pd/TiO2-Multiwall Nanotubes toward Electrocatalytic Oxidation of Formic Acid in Acid Media

The formic acid (HCOOH) oxidation was studied in acid medium at Pd nanoparticles (NPs) supported on TiO₂ electrode. TiO₂ nanotube electrode was prepared using the anodizing method. This method was modified by Pd NPs onto the tube surface, via Pd electrodeposition, Pd NPs supported on vulcan carbon XC-72R and Pd NPs impregned. Pd NPs were synthesized following the colloidal method and characterized by XRD, UV-Vis spectroscopy and SEM. The TiO₂ MWNTs electrode is homogeneously covered by Pd NPs. The Pd/TiO₂-MWNTs performance and electrocatalytic activity were characterized by cyclic voltammetry and chronoamperometry in 0.5 M H₂SO₄ and 2.0 M HCOOH. Results demonstrate that Pd NPs onto TiO₂ nanotubes (NTbs) increased the catalytic activity of Pd NPs for HCOOH oxidation.