Nitrogen Doped Carbon Nanotubes and Nanofibers for Green Hydrogen Production: Similarities in the Nature of Nitrogen Species, Metal–Nitrogen Interaction, and Catalytic Properties

Abstract

The effect of nitrogen doped bamboo-like carbon nanotubes (N−CNTs) on the properties of supported platinum (0.2 and 1 wt %) catalysts in formic acid decomposition for hydrogen production was studied. It was shown that both impregnation and homogeneous precipitation routes led to the formation of electron-deficient platinum stabilized by pyridinic nitrogen sites of the N−CNTs. The electron-deficient platinum species strongly enhanced the activity and selectivity of the Pt/N−CNTs catalysts when compared to the catalysts containing mainly metallic platinum nanoparticles. A comparison of bamboo-like N−CNTs and herring-bone nitrogen doped carbon nanofibers (N−CNFs) as the catalyst support allowed us to conclude that the catalytic properties of supported platinum are determined by its locally one-type interaction with pyridinic nitrogen sites of the N−CNTs or N−CNFs irrespective of substantial structural differences between nanotubes and nanofibers.

Keywords

• hydrogen
• formic acid
• platinum
• nitrogen doped
• carbon nanotubes
• carbon nanofibers