OBTAINING COMPOUNDS Sb2Se3 AND As2Se3 BY BOROHYDRIDE METHOD

By the methods of differential-thermal analysis (DTA), X-ray phase analysis (RFA), scanning electron microscopy (SEM) obtaining the condition of compounds As2Se3 and Sb2Se3 when adding a solution 0,1 M NaBH4 on the stoichiometric amounts on the mixture ratio of NaAsO2/Na2Se=1:3 mmol and Sb(CH3COO)3/Na2Se=1:3 mmol was studied. It was determined that, nano-sized As2Se3 and Sb2Se3 compounds are obtained when thermal processing aqueous solutions of obtained sediments in the autoclave at 150 0C. Their nano-structures are formed when the thermal processing of proper compounds in the vacuum at 250 0C. According to DTA results, nano-sized As2Se3 and Sb2Se3 compounds are appropriately melting at the 358.2 0C and 588.4 0C. According to RFA results, it was determined that As2Se3 compound crystallizes in the monocline syngony (Space gr.: P21/n; a=1.1989 nm, b=0.8981 nm, c=0.4037 nm, =94.70 , Z=4) but Sb2Se3 compound crystallizes in the rhombic syngony (Space gr.: Pbnm; a=1.103 nm, b=1.1544 nm, c=0.3762 nm). Yielding of compounds studied depends on condition of pH, temperature and the amount of sodium borohydride.