Heterostructure of graphene with a two-dimensional crystalline molybdenum trioxide (MoO3) layers

The heterostructure consisting of graphene and two-dimensional (2D) crystalline molybdenum trioxide (MoO₃) layers was fabricated through a wet transfer method using a polymer to transfer the MoO₃ layers from the mica crystal surface. Using a heating plate method, this crystalline MoO₃ was initially grown on mica under normal atmospheric air conditions. Furthermore, the authors demonstrated that the only MoO₃ phase forms on the molybdenum foil following annealing in air, as confirmed by X-ray photoelectron spectroscopy (XPS) study. The resulting graphene heterostructure was examined using optical and atomic force microscopy (AFM). The fabrication method introduced here offers a cost-effective alternative to the more costly and complex ultra-high vacuum techniques used for epitaxial layer fabrication. This graphene heterostructure holds potential as a conductive and transparent anode for the organic light-emitting diode (OLED) technology.

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1. This work was financially supported by the National Science Centre (Poland) under grant 2020/37/B/ST5/03929.

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2. Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).