Bimetallic Face-Centered Cubic Pd–Ag Nano-dendritic Alloys Catalysts Boost Ethanol Electrooxidation

Abstract

The development of green and sustainable energy is important for the current society to address global climate change. Direct ethanol fuel cells have attracted extensive attention at home and abroad due to their environmentally friendly features, high energy density, and ease of management. Herein, a class of alloyed PdAg catalysts with a controllable alloying degree as well as lattice expansion were prepared. The PdAg nano-dendritic alloys (NDAs) exhibit “volcano-type” behavior, where the Pd5Ag1 NDA with a tensile value of 1.0% possesses the highest peak current density (1950 mA mg–1) for ethanol oxidation reaction (EOR), controlled by a dynamic balance of active and blocking species adsorption energy. This electrocatalytic behavior mainly arises from the formation of a crystalline nano-dendritic structure and the synergistic effect between Pd and Ag. Moreover, the kinetics of EOR determined that higher electrocatalytic temperatures and higher concentrations of OH– or C2H5OH are favorable for EOR.