Laser-induced atomic structure evolution of palladium nanoparticles and its effect on ethanol electro-oxidation

The atomic structure of palladium nanoparticles (Pd NPs) is crucial for determining their catalytic performance. In this study, the atomic structure evolution (five-fold twin-stacking fault defect-single crystal) of Pd NPs is accomplished using a nanosecond pulsed laser irradiation method. The mechanism is theoretically investigated by combining finite element analysis (FEA) with molecular dynamics (MD) simulations. The laser irradiation induces a localized temperature field on the Pd NPs and drives the motion of atoms. The Pd NPs undergo fast heating and cooling, and the evolution of the atomic structure is driven by dynamic stress oscillations. The laser-irradiated Pd NPs exhibit improved catalytic activity and anti-CO poisoning ability toward ethanol electrooxidation (EOR). Furthermore, the catalytic mechanism is investigated using the density functional theory (DFT) calculations, which clarify the effects of the stacking fault structure and the micro-strain in improving the catalytic performance of Pd NPs. This study provides a theoretical basis for the laser fabrication of defective nano-catalysts.