Synthesis of Cu₃BiS₃ and AgBiS₂ crystallites with controlled morphology using hypocrellin template and their catalytic role in the polymerization of alkylsilane

Hypocrellins, photoactive compounds isolated from fungus, were first employed as non-surfactant templates in the synthesis of ternary chalcogenide Cu₃BiS₃ and AgBiS₂ crystallites via a facile ethanol-thermal process. It was also found that the used templates, poly (vinylpyrrolidone) (PVP), poly (ethylene glycol) (PEG), and hypocrellins had strong effect on the morphology of synthesized Cu₃BiS₃ and AgBiS₂ and their catalytic polymerization products of an alkylsilane, C₁₈H₃₇SiH₃ with water. In particular, the orthorhombic phase of wittichenite Cu₃BiS₃ with multi-armed microrods morphology and the cubic Schapbachite and hexagonal phase Matildite AgBiS₂ with flower-like morphology were obtained when hypocrellins were used as templates at 180 °C for 20 h. Although, the used templates seem to have little effect on the crystalline grain size, compared with traditional PVP and PEG templates, hypocrellins have exhibited better directing actions. Furthermore, the polymerization products over Cu₃BiS₃ and AgBiS₂ templated by hypocrellins showed good replica of the morphologies before polymerization while the polymerization products over Cu₃BiS₃ and AgBiS₂ templated by PVP and/or PEG exhibited significant morphology change.