Facile microwave-assisted synthesis and characterization of CuSe nanosheets: effect of EDTA concentration

A facile microwave-assisted synthesis approach was used to synthesize a high-quality CuSe nanosheets at different concentration of ethylenediaminetetraacetic acid (EDTA). Analysis of the XRD result revealed the formation of single-phase CuSe with hexagonal (Klockmannite) crystal structure. The crystallite size was found to decrease from 73.10 to 8.40 nm with an increase in EDTA concentration. EDX analysis revealed that all the samples were of the pure phase CuSe corresponding to a 1:1 atomic ratio. Three Raman vibrational modes ascribed to the vibrational bands of CuSe were detected from the Raman spectroscopy. TEM result revealed that a well-tailored layered hexagonal structure was achieved at higher EDTA concentration. The particle size obtained from FESEM micrographs was found to decrease from 75.10 to 12.20 nm with an increase in EDTA concentration. Moreover, the optical bandgap obtained from the UV-Visible diffuse reflectance spectroscopy was found to increase alongside an increase in EDTA concentration, which is attributed to the decrease in the particle size of the as-synthesized CuSe nanosheets. The maximum PL emission of all the samples was centered at 600 nm under an excitation wavelength of 400 nm. Therefore, CuSe nanosheets obtained by the described method could be of great benefit in many applications particularly in optoelectronics and solar cell applications.