Solvothermal synthesis of ternary Cu2SnS3 (CTS) nanostructures in ethylenediamine: effect of different oleic acid concentrations on structural, optical and morphological Properties

Cu2SnS3 (CTS) nanostructures were synthesized by the solvothermal method using oleic acid as an additive. The effects of varying the concentrations of oleic acid on the structural, morphological and optical properties of CTS nanostructures were studied. The properties of the CTS nanostructures were analyzed using X-ray diffraction (XRD), UV-VIS spectroscopy, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). XRD patterns reveal that the synthesized samples exhibit the wurtzite structure with lattice parameters 'a' similar to 3.7 angstrom and 'c' similar to 6.2 angstrom. UV-VIS spectra indicate that the particles have high optical absorption with bandgaps in the range 1.43-1.6 eV, which is ideal for photovoltaic applications. SEM results unveil different morphologies including flakes, beads and spherical particles depending on the amount of oleic acid used. TEM results confirm the size of grains to be around 20-25 nm. (C) 2019 Elsevier Ltd. All rights reserved.