PEG-Assisted Fabrication of Single-Crystalline CuI Nanosheets:  A General Route to\nTwo-Dimensional Nanostructured Materials

Abstract

CuI single-crystalline nanosheets have been prepared for the first time via a PEG-assisted aqueous solution\nroute at room temperature. The thickness and in-plane size of the nanosheets were ca<i>.</i> 60−80 nm and several\nmicrometers, respectively. The two basal surfaces of these nanosheets were (111) planes. The phase\ntransformation temperature and the melting point decreased 8 and 12 °C compared with those of the bulk\nCuI, respectively. The resistance of a single CuI nanosheet was measured by using a conductive AFM tip\nmethod, and a high conductivity of 1.996 × 10^-2 Ω·cm and a photoconduction phenomenon were observed.\nIt is found that the coexistence of PEG600 and SDBS was vital to the formation of nanosheets. This simple\nroute could be employed to synthesize more 2D nanostructures as a general process.