Abstract
In this paper, we report a facile, low cost synthesis and characterization of kesterite Cu 2ZnSn(S x,Se 1-x) 4 (CZTSSe) nanocrystals (NCs) by a two-step process involving a solution-based precursor and a post-annealing route. The effects of different Se vaporization temperatures, ranging from 350 °C to 550 °C, on the structural, chemical, compositional, and optical properties of CZTSSe NCs were investigated. X-ray diffraction patterns, Raman spectroscopy, and transmission electron microscopy results indicated that the precursor powder showed several broad peaks that could not be assigned to Cu 2ZnSnS 4 (CZTS), ZnS, Cu 2-xS, Sn 2S 3 and Cu 2SnS 3. However, the post-annealed NCs with and without Se vaporization were a single kesterite CZTS phase without a secondary phase. UV-vis spectroscopy results showed that the absorption coefficients of all the post-annealed NCs were over 10 4 cm -1 in the visible region, and the optical band gap energy decreased systematically from 1.46 eV to 1.14 eV with increasing Se vaporization temperatures.
Original language | English (US) |
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Pages (from-to) | 21727-21732 |
Number of pages | 6 |
Journal | Journal of Materials Chemistry |
Volume | 22 |
Issue number | 40 |
DOIs | |
State | Published - Oct 28 2012 |
Externally published | Yes |