The role of nitrogen defects for stabilization of Pt-group metals on graphene layers and hydrogen generation from formic acid


L.G. Bulusheva, D.A. Bulushev A.V. Okotub


Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk, Russia



Abstract:

Replacing the carbon atom in graphene network with nitrogen can significantly change the reactivity of the material and improve its characteristics associated with the doping. In particular, our studies have shown that Pd on a nitrogen-containing carbon (CNx) support is a more effective catalyst for the decomposition of formic acid than Pd on a pure carbon support of the same morphology [1]. A comparative study of supports and catalytic systems by the XPS method and NEXAFS after reduction in hydrogen atmosphere in the X-ray spectrometer chamber revealed the presence of components corresponding to the Pd-N bond, which was due to the stabilization of the metal atoms by the nitrogen defect. High-resolution transmission electron microscopy confirmed the presence of metal on a carbon grid in atomic form. To determine the types of nitrogen defects that most effectively interact with Pd, Pt, and Ru, quantum-chemical calculations of model systems in the density functional theory approximation were carried out [2]. Regardless of the type of defect, the binding energy with CNx increases in a set of metals Pd