Synthesis of CuInS2 nanocrystals from a molecular complex - characterization of the orthorhombic domain structure

摘要

CuInS2 nanocrystals were synthesized by thermal decomposition of the molecular precursor [(Me3P)(3)Cu-(SC2H4S)(InPr2)-Pr-i] in the presence of oleylamine in dioctyl phthalate. According to X-ray diffraction patterns, the as-synthesized CuInS2 nanocrystals crystallize in the wurtzite type structure. High-resolution transmission electron images and selected area electron diffraction patterns reveal a nanodomain structure. The individual domains are approximately 5-10 nm in size and characterized by short-range cation ordering, which assuming hypothetical long-range order, corresponds to an orthorhombic superstructure (space group Pmc2(1), a = 4.09 +/- 0.01 angstrom, b = 7.16 +/- 0.02 angstrom and c = 6.56 +/- 0.03 angstrom). The domains are separated by twin and antiphase boundaries.