Advances in the synthesis and characterization of phosphorene for bandgap tailoring – a comprehensive review

Abstract

Phosphorene is a two-dimensional (2D) material obtained from black phosphorus and has attracted considerable attention for its outstanding electronic properties, such as tunable bandgap and high carrier mobility. This review presents the structural and morphological study of direct bandgap phosphorene by atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), which verified the successful exfoliation and uniformity of the nanosheets. Also, the crystalline studies and optical properties investigated through Raman spectroscopy, X-ray diffraction (XRD) and ultraviolet-visible (UV-Vis) spectroscopy have been presented. Photoluminescence (PL) spectroscopy can measure the bandgap energy, demonstrating tunability which is dependent on the number of layers. The increase from 0.33 eV in the bulk to 1.88 eV in bilayers showcases phosphorene's band gap evolution in large-scale synthesis, with a higher-energy transition from 2.0 eV to 3.23 eV highlighting its unique optoelectronic properties. The characterization of phosphorene underscores its promising attributes for bandgap formation, with potential applications ranging from transistors to photodetectors.