Modulation of structures of CuInS2 nanoparticles grown with ethylxanthate salts

Chalcopyrite, wurtzite and zincblende structured CuInS2 nanoparticles of 2.6-11.4 nm with high quality and strong luminescence were successfully synthesized by decomposing ethylxanthate salts. The effects of ligands and nucleus structures on nanoparticle structures and properties were studied. The nanoparticle structures could be adjusted by controlling the nucleus structures through tuning the injecting sequences of Cu-S and In-S precursors. The nanoparticle structures could also be adjusted to be wurtzite or chalcopyrite by adjusting the capping ligand ratio of tri-n-octylphosphine/oleic acid/oleylamine. An increase in tri-n-octylphosphine ratio would induce the selective growth of chalcopyrite structured CuInS2 nanoparticles. The mechanisms in CuInS2 crystal structure selectivity were discussed, which provides an insight into controlled synthesis of other ternary chalcogenides. (C) 2015 Elsevier B.V. All rights reserved.