Open AccessVan der Waals hetero-structures of 1H-MoS2 and N-substituted graphene for catalysis of hydrogen evolution reaction
Author(s) -
Lakshay Dheer,
Satadeep Bhattacharjee,
Seung Cheol Lee,
Umesh V. Waghmare
Publication year - 2019
Publication title -
materials research express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.383
H-Index - 35
ISSN - 2053-1591
DOI - 10.1088/2053-1591/ab6c0e
Subject(s) - van der waals force , graphene , catalysis , materials science , crystallography , chemistry , molecule , nanotechnology , organic chemistry
First-principles theoretical analysis of the catalytic activity of van der Waals hetero-structures of 1H-MoS 2 and graphene substituted with three chemical types of nitrogen species (i) Graphitic (G), (ii) Pyridinic (Pn) and (iii) Pyrrolic (Pr), for application in catalysis of hydrogen evolution reaction (HER) has been presented. Graphitic and pyrrolic N substituents result in n-type electronic structure, whereas substitution of pyridinic N imparts p-type electronic character to the hetero-structure. Work functions ( φ ) of the hetero-structures suggest that graphitic N-graphene:MoS 2 hetero-structure ( φ = 3.8 eV ) is expected to be effective in catalysing the reduction of H + to evolve H 2 . 1H-MoS 2 monolayer in the hetero-structure contributes by enabling increased H 2 O adsorption and offsetting the band edge energies optimal for the catalytic activity. Near optimum Gibbs free energy of H-adsorption ( Δ G H ) were obtained for graphitic ( Δ G H ∼ 0.29 eV) and pyrrolic ( Δ G H ∼ −0.2 eV) N-graphene:MoS 2 hetero-structures. Our work showcases how catalytic and electronic properties of the N-doped graphene:MoS 2 hetero-structure depends on the chemical identity of N-sites and uncovers a route to 2D hetero-structures with high catalytic activity.