From Amorphous Red Phosphorus to a Few Layers of Black Phosphorus: A Low-cost and Efficient Preparation Process

In this work, we present an efficiency synthesis method of phosphorene from red phosphorus by means of black phosphorus. The latter was synthesized by using copper, tin, tin iodide and red phosphorus as precursor at low pressure-temperature. Characterizations with powder X-ray diffraction, scanning electron microscopy (SEM), energy dispersive spectrometry (EDX), high-resolution TEM (HR-TEM) and Raman spectroscopy were performed to confirm the high quality and purity of black phosphorus crystal. Liquid phase method was used to exfoliate black phosphorus to phosphorene in N-methyl-2-pyrrolidone (NMP) as solvent. Atomic force microscopy and STEM were used to confirm the exfoliation of black phophorus in a few layers of phophorene.