Soft-Chemical Method for Synthesizing Intermetallic Antimonide Nanocrystals from Ternary Chalcogenide

The synthesis of intermetallic antimonides usually depends on either the high-temperature alloying technique from high-purity metals or the flux method in highly poisonous Pb-melt. In this paper, we introduced a soft-chemical method to synthesize intermetallic antimonides from ternary chalcogenide precursors under an argon atmosphere below 200 °C. Powder X-ray diffraction and compositional analysis clearly indicate that a new phase of the Ag₃Sb nanocrystal was synthesized from the Ag₃SbS₃ precursors. Three types of trialkylphosphines (TAPs) were applied as desulfurization agents, and the transformation mechanism was elucidated. The capability of the desulfurization agent follows the sequence of triphenylphosphine (TPP) > tributylphosphine (TBP) > trioctylphosphine (TOP). Besides, this TAP-driven desulfurization route to synthesize the intermetallic phase could also be possible for AgSbSe₂ and Sb₂S₃. Therefore, this paper provides an efficient and mild technique for the fabrication of intermetallic nanocrystals.