Penetration Barrier of Water through Graphynes' Pores: First-Principles Predictions and Force Field Optimization.
Graphynes are novel two-dimensional carbon-based materials that have been proposed as molecular filters, especially for water purification technologies. We carry out first-principles electronic structure calculations at the MP2C level of theory to assess the interaction between water and graphyne, graphdiyne, and graphtriyne pores. The computed penetration barriers suggest that water transport is unfeasible through graphyne while being unimpeded for graphtriyne. For graphdiyne, with a pore size almost matching that of water, a low barrier is found that in turn disappears if an active hydrogen bond with an additional water molecule on the opposite side of the opening is considered. Thus, in contrast with previous determinations, our results do not exclude graphdiyne as a promising membrane for water filtration. In fact, present calculations lead to water permeation probabilities that are 2 orders of magnitude larger than estimations based on common force fields. A new pair potential for the water-carbon noncovalent component of the interaction is proposed for molecular dynamics simulations involving graphdiyne and water.
†Instituto de Fı́sica Fundamental, Consejo Superior de Investigaciones Cientı́ficas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
Massimiliano
M
Bartolomei
†Instituto de Fı́sica Fundamental, Consejo Superior de Investigaciones Cientı́ficas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
Estela
E
Carmona-Novillo
†Instituto de Fı́sica Fundamental, Consejo Superior de Investigaciones Cientı́ficas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
Marta I
MI
Hernández
†Instituto de Fı́sica Fundamental, Consejo Superior de Investigaciones Cientı́ficas (IFF-CSIC), Serrano 123, 28006 Madrid, Spain.
José
J
Campos-Martínez
‡Dipartimento di Chimica, Universitá di Perugia, Perugia, Italia.
Fernando
F
Pirani
¶Department of Chemical System Engineering, School of Engineering, University of Tokyo, Tokio, Japan.
Giacomo
G
Giorgi
¶Department of Chemical System Engineering, School of Engineering, University of Tokyo, Tokio, Japan.
Koichi
K
Yamashita
ab initio calculations; graphdiyne; graphyne; nanofiltration; porous materials; water purification