Growth and characterization of rhenium-doped MoS2 single crystals

Single crystals of rhenium-doped MoS2 have been grown by chemical vapor transport method using bromine as a transporting agent. Single crystalline platelets up to 10 x 10 mm(2) surface area and 2 mm in thickness were obtained. By analyzing the X-ray diffraction profile, the structure of the single crystals shows rhombohedral symmetry. Temperature-dependent electrical resistivity and Hall coefficient were measured between 20 and 300 K using the van der Pauw technique. The hall coefficient measurement indicates that all the samples are n-type in nature. The optical absorption measurements reveal that rhenium-doped MoS2 is an indirect semiconductor. The energy gap shows a red shift by increasing the doping concentrations. (C) 1999 Elsevier Science B.V. All rights reserved.