Regensburg 2013 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
DS: Fachverband Dünne Schichten
DS 23: Focus Session: Thin Film Photovoltaic Materials and Solar Cells II
DS 23.13: Vortrag
Mittwoch, 13. März 2013, 18:00–18:15, H8
Photoluminescence and Raman scattering in wurtzite Cu2ZnSn(S1-x,Sex)4 nanocrystals — •Sergej Levcenko1, Thomas Unold1, Ajay Singh2,3, Shalini Singh2,3, and Kevin M Ryan2,3 — 1Helmholtz Zentrum Berlin für Materialien und Energie, Berlin, Germany — 2SFI-Strategic Research Cluster in Solar Energy Conversion, University of Limerick, Ireland — 3Materials and Surface Science Institute, University of Limerick, Ireland
Cu2ZnSn(S1-x,Sex)4 (CZTSSe) semiconductors gain much attention due to their potential photovoltaic application. Recently, by nanocrystal chemistry approach the formation of the new wurtzite crystal phase of CZTS and CZTSe which is thermodynamically unstable in a bulk phase (kesterite/stannite) were reported. Here we present the vibrational and optical properties of wurtzite- CZTSSE nanocrystals as a function of x characterized by Raman and photoluminescence. The pseudo-spherical CZTSSE nanocrystals with the diameter of about 20 nm were prepared by colloidal chemistry method. The Raman spectra of the CZTSSE nanostructures show a two mode behavior. The intensive CZTSE-like mode strongly shifts from 191 cm-1 for x=1 to 225 cm-1 for x=0.15, while the intensive CZTS-like mode barely shifts from 333 cm-1 for x=0 to 329 cm-1 for x=0.8. The low temperature CZTSSE PL spectra show one broad PL band which is gradually tuned from 1.4 eV for x=0 to 0.9 for x=0.15. The observed PL band most likely originates from near band edge emission of wurtzite CZTSSE nanocrystals.