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arXiv · 2305.06708

Interfacial two-dimensional oxide enhances photocatalytic activity of graphene/titania via electronic structure modification

Dario De Angelis·Francesco Presel·Naila Jabeen·Luca Bignardi·Daniel Lizzit·Paolo Lacovig·Silvano Lizzit·Tiziano Montini·Paolo Fornasiero·Dario Alfè·Alessandro Baraldi
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Abstract

A two-dimensional layer of oxide reveals itself as a essential element to drive the photocatalytic activity in a nanostructured hybrid material, which combines high-quality epitaxial graphene and titanium dioxide nanoparticles. In particular, it has been revealed that the addition of a 2D Ti oxide layer sandwiched between graphene and metal induces a p-doping of graphene and a consistent shift in the Ti d states. These modifications induced by the interfacial oxide layer induce a reduction of the probability of charge carrier recombination and enhance the photocatalytic activity of the heterostructure. This is indicative of a capital role played by thin oxide films in fine-tuning the properties of heterostructures based on graphene and pave the way to new combinations of graphene/oxides for photocatalysis-oriented applications.

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Dario De Angelis, Francesco Presel, Naila Jabeen, Luca Bignardi, Daniel Lizzit, Paolo Lacovig, Silvano Lizzit, Tiziano Montini, Paolo Fornasiero, Dario Alfè, Alessandro Baraldi. 2023-05-11. Interfacial two-dimensional oxide enhances photocatalytic activity of graphene/titania via electronic structure modification. https://doi.org/10.1016/j.carbon.2019.10.053

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