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

Abstract

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.