Two Distinct Transitions in Cu(x)InS2 Quantum Dots. Bandgap versus Sub-Bandgap Excitations in Copper-Deficient Structures.

Autor:	Jara DH; Radiation Laboratory, Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States., Stamplecoskie KG; Radiation Laboratory, Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States., Kamat PV; Radiation Laboratory, Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States.
Jazyk:	angličtina
Zdroj:	The journal of physical chemistry letters [J Phys Chem Lett] 2016 Apr 21; Vol. 7 (8), pp. 1452-9. Date of Electronic Publication: 2016 Apr 06.
DOI:	10.1021/acs.jpclett.6b00571
Abstrakt:	Cu-deficient CuInS2 quantum dots (QDs) synthesized by varying the [Cu]:[In] ratio allow modulation of optical properties as well as identification of the radiative emission pathways. Absorption and emission spectral features showed a strong dependence on the [Cu]:[In] ratio of CuxInS2 QDs, indicating two independent optical transitions. These effects are pronounced in transient absorption spectra. The bleaching of band edge absorption and broad tail absorption bands in the subpicosecond-nanosecond time scale provide further evidence for the dual optical transitions. The recombination process as monitored by photoemission decay indicated the involvement of surface traps in addition to the bandgap and sub-bandgap transitions. Better understanding of the origin of the optical transitions and their influence on the photodynamics will enable utilization of ternary semiconductor quantum dots in display and photovoltaic devices.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu