The presence of defects in the graphenic layers deposited on metal surfaces modifies the nature of the interaction. Unsaturated carbon atoms, due to vacancies in the lattice, form strong organometallic bonds with surface metal atoms that highly enhance the binding energy between the two materials. We investigate by means of a wide set of dispersion-corrected density functional theory calculations how such strong chemical bonds affect both the electronic properties of these hybrid interfaces and the chemical reactivity with water, which is commonly present in the working conditions. We compare different metal substrates (Cu vs Pt) that present a different type of interaction with graphene and with defective graphene. This comparative analysis allows us to unravel the controlling factors of water reactivity, the role played by the carbon vacancies and by the confinement or “graphene cover effect”. Water is capable of breaking the C–Cu bond by dissociating at the undercoordinated carbon atom of the vacancy, restoring the weak van der Waals type of interaction between the two materials that allows for an easy detachment of graphene from the metal, but the same is not true in the case of Pt, where C–Pt bonds are much stronger. These conclusions can be used to rationalize water reactivity at other defective graphene/metal interfaces.

Perilli, D., Ferrighi, L., Selli, D., & Di Valentin, C. (2018). Water at the Interface Between Defective Graphene and Cu or Pt (111) Surface. Intervento presentato a: Graphene 2018, Dresden, Germany.

Water at the Interface Between Defective Graphene and Cu or Pt (111) Surface

Perilli, D;Ferrighi, L;Selli, D;Di Valentin, C
2018

Abstract

The presence of defects in the graphenic layers deposited on metal surfaces modifies the nature of the interaction. Unsaturated carbon atoms, due to vacancies in the lattice, form strong organometallic bonds with surface metal atoms that highly enhance the binding energy between the two materials. We investigate by means of a wide set of dispersion-corrected density functional theory calculations how such strong chemical bonds affect both the electronic properties of these hybrid interfaces and the chemical reactivity with water, which is commonly present in the working conditions. We compare different metal substrates (Cu vs Pt) that present a different type of interaction with graphene and with defective graphene. This comparative analysis allows us to unravel the controlling factors of water reactivity, the role played by the carbon vacancies and by the confinement or “graphene cover effect”. Water is capable of breaking the C–Cu bond by dissociating at the undercoordinated carbon atom of the vacancy, restoring the weak van der Waals type of interaction between the two materials that allows for an easy detachment of graphene from the metal, but the same is not true in the case of Pt, where C–Pt bonds are much stronger. These conclusions can be used to rationalize water reactivity at other defective graphene/metal interfaces.
No
abstract + poster
Scientifica
DFT, graphene-metal interfaces, water dissociation, vacancy
English
Graphene 2018
Perilli, D., Ferrighi, L., Selli, D., & Di Valentin, C. (2018). Water at the Interface Between Defective Graphene and Cu or Pt (111) Surface. Intervento presentato a: Graphene 2018, Dresden, Germany.
Perilli, D; Ferrighi, L; Selli, D; Di Valentin, C
File in questo prodotto:
File Dimensione Formato  
poster_DanielePerilli.pdf

accesso aperto

Tipologia di allegato: Author’s Accepted Manuscript, AAM (Post-print)
Dimensione 562 kB
Formato Adobe PDF
562 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/10281/263418
Citazioni
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
Social impact