Synthesis of Ternary Chalcogenides in Cu-As-Se Systems by the Solvothermal Method in Organic Medium and Production of Nano-and Microparticles

Abstract

Ternary selenides CuAsSe2 and Cu3AsSe3 were synthesized by the solvothermal method from H [CuCl2]-As2Se3-C2H6O2 system. Nano and microparticles were obtained, and their physical and chemical properties were studied. During syntheses, sodium metaarsenite and copper (I) chloride are mixed in ethylene glycol, and a solution of Na2SeSO3 is added as a selenidation reagent according to stoichiometry. These solutions were added to an experimental vessel, placed in a Teflon cuvette, sealed, and placed in a microwave electric heater. The samples are kept in the oven at 413-443 K for 10 hours. After the process, the precipitate is filtered through a glass filter, washed first with dilute hydrochloric acid and distilled water, and finally with ethyl alcohol, and dried in a vacuum at 333-343 K. The productivity of the samples was 90-92 %. Compounds formed at a temperature of 453-473 K dissolve. Nanoparticles of compounds obtained at a temperature of 413-433 K have an irregular shape. Nanoparticles obtained at a temperature of 443 K are in the form of plates. The results of the X-ray phase analysis showed that the compounds correspond to cubic zirconia and belong to the Pm3m spatial structure. Lattice parameters of CuAsSe2 compound: a = 5.513 Å, Z = 2 and lattice parameters of Cu3AsSe3 compound: a = 5.76 Å, Z = 1. Based on DTA results, the CuAsSe2 compound melts congruently at 743 K, while the Cu3AsSe3 compound decomposes at 773 K.