Exploring reaction mechanisms for CO oxidation on boron-doped carbon nanotubes: A computational approach

Abstract

Spin-polarized first-principles computations are carried out to illustrate the catalytic mechanisms of CO oxidation on the (5, 5) boron-doped carbon nanotube (BCNT). BCNTs with two kind of boron content of 1 and 2 atom % are studied. The calculations show that O2 species prefers to partially reduce and chemically bind at CB site via the side-on configuration with the adsorption energies of −0.85 eV for the BCNT with boron content of 1 atom % and −1.27 ~ −1.29 eV for the BCNT with boron content of 2 atom %. The partially reduced O2 species can further react with CO via the Eley-Rideal (ER) mechanism by overcoming a small energy barrier of 0.34 eV for the BCNT with boron content of 1 atom % and 0.42 eV for the BCNT with boron content of 2 atom %. Second reaction of CO oxidation occurs by the reaction of CO + O → CO2 with a slight energy barriers of 0.12 and 0.14 eV for the BCNT with boron content of 1 and 2 atom %, respectively. Our results manifest that the boron-doped CNT can be an advanced metal-free catalyst for CO oxidation.