Journal of Nanomedicine & Nanotechnology

Catalysis under cover: Enhanced reactivity at the interface between (doped) graphene and anatase TiO2

22^nd International Conference and Expo on Nanoscience and Molecular Nanotechnology

November 06-08, 2017 | Frankfurt, Germany

Lara Ferrighi, Martina Datteo, Gianluca Fazio and Cristiana Di Valentin

Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via Cozzi 55, 20125 Milano, Italy

Posters & Accepted Abstracts: J Nanomed Nanotechnol

Abstract:

The �??catalysis under cover�?� involves chemical processes which take place in the confined zone between a 2D material, such as graphene, h-BN, or MoS2, and the surface of an underlying support, such as a metal or a semiconducting oxide [1,2]. The hybrid interface between graphene and anatase TiO2 is extremely important for photocatalytic and catalytic applications because of the excellent and complementary properties of the two materials [3]. We investigate and discuss the reactivity of O2 and H2O on top and at the interface of this hybrid system by means of a wide set of dispersion-corrected hybrid density functional calculations [4]. Both pure and boron- or nitrogen-doped graphene are interfaced with the most stable (101) anatase surface of TiO2 in order to improve the chemical activity of the C-layer. Especially in the case of boron, an enhanced reactivity toward O2 dissociation is observed as a result of both the contribution of the dopant and of the confinement effect in the bidimensional area between the two surfaces. Extremely stable dissociation products are observed where the boron atom bridges the two systems by forming very stable B-O covalent bonds. Interestingly, the B defect in graphene could also act as the transfer channel of oxygen atoms from the top side across the C atomic layer into the G/TiO2 interface. On the contrary, the same conditions are not found to favor water dissociation, proving that the �??catalysis under cover�?� is not a general effect, but rather highly depends on the interfacing material properties, on the presence of defects and impurities and on the specific reaction involved [5].

Biography :

Martina Datteo graduated in Chemistry in 2016 at the University of Milano Bicocca, with a thesis on the graphene/anatase (101) interface. Her work of bachelor and master thesis has been included in two international peer- reviewed articles. She has received ‘Fondazione Grazioli’ prize for her master thesis. She is now pursing her PhD degree under the supervisor of Prof. Cristiana Di Valentin. The topic of the thesis is “Computational study of smart bioinorganic hybrids for nanomedicine”.