Porous three-dimensional network of Pd–Cu aerogel toward formic acid oxidation

Abstract

New self-assembled architectures have received great interest in nanotechnology, and are a highly desired target in recent studies. Among self-assembled architectures, noble metal aerogels are an important class owing to their collective characters as well as widespread applications. The synthesis of noble metal aerogels still faces several obstacles such as long hydrogel creation time and complicated multistep strategies. In this paper, we propose an efficient and useful approach to create the three-dimensional network of a Pd–Cu aerogel. This way offers a number of advantages including one-pot synthesis, simplicity, and short time to prepare the hydrogel. The Pd–Cu aerogel was prepared by the reduction of H₂PdCl₄ and CuCl₂ in the presence of sodium carbonate by using glyoxylic acid monohydrate as a reducing agent followed by supercritical CO₂ drying. The Pd–Cu aerogel was applied as an anode catalyst for electrooxidation process of formic acid, and depicts much higher electrocatalytic activity and durability compared to the Pd/C. We believe that the exceptional three-dimensional nanostructures fabricated by this route are powerful and promising catalysts for application in direct formic acid fuel cells (DFAFCs), which may open great opportunities for widespread applications such as catalysis, sensors, optoelectronics, electrochemical energy systems, etc.