Abstract
Recently, next-generation two-dimensional (2D) materials to replace graphene inspired people to study other types of elements. Among them, black phosphorus (BP) have attracted great interests for their wide range of optical bandgap from near IR to visible wavelength and remarkable high hole mobility. However, one of critical challenges for the applications of BP to devices is its instability. Herein, we introduce a very simple method to fabricate a thin and stable BP. Thermal annealing in air above 200 °C creates a stable BP oxide layer on top of the BP surface. In the meantime, thermal oxidation reduces the thickness of the BP by etching the top BP layer. In addition, we find that the protective layer is composed of P2O5 by using x-ray photoelectron spectroscopy (XPS). We suggest that the thermal annealing provides an effective and simple strategy to fabricate high-quality BP-based electronic devices.
