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.