Utilizing ballistic nanoparticle impact to reconfigure the metal support interaction in Pt-TiN electrocatalysts.

ABSTRACT

Tuning the metal support interaction (MSI) in heterogeneous catalysts is of utmost importance for various applications in different catalysis reactions. Pt-TiN systems are strong contenders for commercial catalysts, although the charge screening of Pt and non-involvement of N reduces their effective MSI and limits it to the Pt-Ti interface. Here, the bias driven landing of gas phase synthesized Pt nanoparticles (NPs) is used to change the nature of the MSI and enhance the charge transfer phenomenon. Bias driven landing of the Pt NPs translates their impact energies to the TiN surface, resulting in a weakening of the Ti-N bonds. This facilitates a new interaction between the Pt and N atoms, resulting in an electronic equilibration in the N-Pt-Ti triumvirate, nullifying the charge screening of Pt. This change in the nature of the MSI enables long range charge transfer throughout the catalyst surface and an increase in the electrocatalytic hydrogen evolution reaction (HER) activity of the Pt-TiN system.