Formation of Group 11 Bismuth Sulfide Nanoparticles Using Bismuth Dithioates under Mild Conditions

The formation of mixed-metal sulfides with the general structure AgBiS₂ and Cu₃ BiS₂ by a simple two-step process utilizing bismuth dithiocarboxylates as Bi and S precursors is described. A sonochemical reaction of Bi₂ O₃ with six different aryl dithioic acids: dithiobenzoic acid (BDT-H), 4-methoxydithiobenzoic acid (4-MBDT-H), 3-methyldithiobenzoic acid (3-MBDT-H), 2-mesitylenedithioic acid (2-MDT-H), 4-fluorodithiobenzoic acid (4-FBDT-H), and 2-thiophenedithioic acid (2-TDT-H) resulted in the corresponding complexes: [Bi(BDT)₃ ] 1, [Bi(4-MBDT)₃ ] 2, [{Bi(3-MBDT)₃ }₂ ⋅C₇ H₈ ] (3₂ ⋅C₇ H₈ ), [Bi(2-MDT)₃ ] 4, [Bi(4-FBDT)₃ ] 5 and [Bi(2-TDT)₃ ] 6. Microwave irradiation of these bismuth(III)aryldithioate complexes with AgNO₃ or CuCl under mild reaction conditions (140 °C) resulted in the respective mixed-metal sulfides. Attempt to synthesize AuBiS₂ using similar reaction protocols were unsuccessful, resulting only in the formation of elemental Au⁰ , S₈ and BiOCl.