Eur. Phys. J. B (2015) 88: 303
https://doi.org/10.1140/epjb/e2015-60557-7

Regular Article

First principles calculation of CH₄ decomposition on nickel (111) surface

¹ Department of Physics, Kumamoto University, 2-39-1 Kurokami Chuo-ku, 860-8555 Kumamoto, Japan
² Faculty of Engineering, Universitas Muhammadiyah Ponorogo, Jl. Budi Utomo No. 10, 63471 Ponorogo, Indonesia
³ Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, 113-8656 Tokyo, Japan

^a e-mail: Rizal.Arifin@gmail.com

Received: 9 July 2015
Received in final form: 27 September 2015
Published online: 18 November 2015

Abstract

The mechanism of the CH₄ decomposition on the nickel (111) surface is investigated by first principles calculations. The activation energy of each reaction is calculated using nudged elastic band method. The activation energy of hydrogen dissociation from a CH₂ fragment is found much lower than the one of a CH₃ fragment. This result is consistent with the fact, observed in our previous molecular dynamics (MD) simulations, that the CH₃ fragment is dissociated into a CH fragment and two hydrogen atoms spontaneously. The effects of finite temperature at 1500 K on the decomposition reaction of a CH₄ molecule and its fragments are also investigated using constraint MD method. While the temperature effects are barely visible in CH₄ and CH₂ dissociation processes, they reduce the activation free energy of hydrogen dissociation from CH₃ and CH fragments largely.