Multifaceted electronic coupling in Pd–Ag nanoparticles on nucleation-rich WO3 for accelerated ethanol oxidation

Abstract

Tungsten trioxide (WO3) is recognized as one of the promising materials for catalyst support. However, its practical application is still restricted by the low specific surface area and the relatively low conduction band level. An efficient hydrothermal and room temperature plasma technique was employed to synthesize WO3 nanoparticles (designated as WO3-Ar), resulting in a higher surface area and the creation of substantial oxygen vacancies on the WO3 surface. Subsequently, Pd and Ag nanoparticles were deposited onto the WO3 nanoparticles, which are characterized by a high specific surface area and numerous oxygen vacancies, through hydrogen reduction (PdAg/WO3-Ar). Electrochemical tests indicate that the PdAg/WO3-Ar catalysts exhibit superior electrocatalytic efficiency compared to the PdAg/C catalyst. The significantly higher electrocatalytic activity is attributed to several factors: (1) The oxygen vacancy defects and the high unique specific surface area of WO3-Ar facilitate the anchoring of Pd–Ag nanoparticles and enhance the electrocatalytic performance of Pd–Ag nanoparticles in PdAg/WO3-Ar catalysts. (2) A catalyst-support interaction exists between Pd–Ag and WO3-Ar, which significantly boosts the catalytic performance of the PdAg/WO3-Ar catalyst.