Highly dispersed PtPd on graphitic nanofibers and its heavy d-Π effect

The strong Pt-carbon interaction is a very promising way to high-performance design of electrocatalysts. However, the heavy d-π overlap, a high strength of Pt-C bonding, in sp² bonded graphitic carbons with low level of defects is rarely reported. Herein, PtPd nanoparticles and graphitic carbon nanofibers (PtPd/CNF) have been integrated via heavy d-π overlap by an interfacial wettability approach and their formation mechanism has also been fully elucidated. The features of strong d-π overlap and high dispersion of metals offer PtPd/CNF with enhanced ORR activity (5.8 folds of specific activity than commercial Pt/C), and excellent structural stability and electrocatalytic durability. A new “heavy d-π overlap” concept, characteristics, and mechanism are proposed at an atomic-/nanoscale to clarify the generation of the predictive interaction as well as the interface charge transfer. It is believed that the study on heavy d-π overlap sheds new light on the fundamental aspects of the nature of Pt-C interaction.