Palladium nanoparticles anchored on NCNTs@NGS with a three-dimensional sandwich-stacked framework as an advanced electrocatalyst for ethanol oxidation

Abstract

A new electrocatalyst (denoted as Pd/NCNTs@NGS) with a three-dimensional sandwich-stacked framework was fabricated through a facile hydrothermal method (to build the NCNTs@NGS by inserting nitrogen-doped truncated carbon nanotubes into nitrogen-doped graphene nanosheets) followed by a simple chemical reduction (to anchor the palladium nanoparticles). The unique architecture and composition of the three-dimensional sandwich-stacked framework for Pd/NCNTs@NGS supply abundant active sites to anchor nanoparticles and provide a fast channel for electrons, reactants and products during the reaction process. Furthermore, the NCNTs can reinforce the three-dimensional rigid skeletal substructure of NCNTs@NGS. Thanks to the above-mentioned advantages, the Pd/NCNTs@NGS displays an excellent electrochemical behavior in alkaline media for the ethanol oxidation reaction, including high electrocatalytic activity, accelerated kinetics, forceful anti-CO poisoning ability and long-term stability. Therefore, it is believed that the Pd/NCNTs@NGS will be a promising candidate as an anode catalyst for direct ethanol fuel cells, and the NCNTs@NGS will also be used to design other electrocatalysts as superior supporting materials.