MXenes as promising catalysts for water dissociation

Two-dimensional few-layered transition-metal nitrides and carbides, called MXenes, have attracted a great interest given their large surface areas and their unique physicochemical properties. Motivated by the known reactivity of surfaces of bulk transition metal carbides on the mechanism behind the...

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Detalles Bibliográficos
Autores: Gouveia, José D., Morales García, Ángel, Viñes Solana, Francesc, Illas i Riera, Francesc, Gomes, José R. B.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2019
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/165755
Acceso en línea:https://hdl.handle.net/2445/165755
Access Level:acceso abierto
Palabra clave:Carburs
Catàlisi
Dissociació (Química)
Teoria del funcional de densitat
Metalls de transició
Carbides
Catalysis
Dissociation
Density functionals
Transition metals
Descripción
Sumario:Two-dimensional few-layered transition-metal nitrides and carbides, called MXenes, have attracted a great interest given their large surface areas and their unique physicochemical properties. Motivated by the known reactivity of surfaces of bulk transition metal carbides on the mechanism behind the water-gas shift (WGS) reaction, density functional theory (DFT) calculations were employed to investigate the bonding of water and its dissociation on a set of eighteen M2X MXene (M = Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W, while X = C or N) surfaces. Here it is shown that all the studied MXenes exothermically adsorb water, with adsorption energies ranging from -1.43 to -2.94 eV, and greatly facilitate its dissociation, with energy barriers below 0.44 eV. These results reinforce the role of MXenes in promoting water dissociation, effectively suggesting their potential as catalysts for industrially relevant processes such as the WGS reaction.