title: Graphene functionalised by laser-ablated V2O5for a highly sensitive NH3sensor.
abstract: Graphene has been recognized as a promising gas sensing material. The response of graphene-based sensors can be radically improved by introducing defects in graphene using, for example, metal or metal oxide nanoparticles. We have functionalised CVD grown, single-layer graphene by applying pulsed laser deposition (PLD) of V2O5which resulted in a thin V2O5layer on graphene with average thickness of ≈0.6 nm. From Raman spectroscopy, it was concluded that the PLD process also induced defects in graphene. Compared to unmodified graphene, the obtained chemiresistive sensor showed considerable improvement of sensing ammonia at room temperature. In addition, the response time, sensitivity and reversibility were essentially enhanced due to graphene functionalisation by laser deposited V2O5. This can be explained by an increased surface density of gas adsorption sites introduced by high energy atoms in laser ablation plasma and formation of nanophase boundaries between deposited V2O5and graphene.
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Margus
authors.initials: M
authors.lastname: Kodu
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Artjom
authors.initials: A
authors.lastname: Berholts
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Tauno
authors.initials: T
authors.lastname: Kahro
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Mati
authors.initials: M
authors.lastname: Kook
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Peeter
authors.initials: P
authors.lastname: Ritslaid
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Helina
authors.initials: H
authors.lastname: Seemen
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Tea
authors.initials: T
authors.lastname: Avarmaa
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Harry
authors.initials: H
authors.lastname: Alles
authors.affiliation: Institute of Physics, University of Tartu, W. Ostwald Street 1, EE50411 Tartu, Estonia.
authors.forename: Raivo
authors.initials: R
authors.lastname: Jaaniso
keywords: UV light activation; ammonia; electric conductivity; gas sensor; graphene; pulsed laser deposition; vanadium(V) oxide