Optical Characterization of Colloidal AgInS2 Quantum Dots Synthesized from Aqueous Solutions

Authors B.V. Lopushanska1, Y.M. Azhniuk1,2 , I.P. Studenyak1, V.V. Lopushansky2, A.V. Gomonnai1,2 , D.R.T. Zahn3

1Uzhhorod National University. 46, Pidhirna St., 88000 Uzhhorod, Ukraine

2Institute of Electron Physics, NASU, 21, Universytetska St., 88017 Uzhhorod, Ukraine

3Semiconductor Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany

Issue Volume 14, Year 2022, Number 4
Dates Received 24 April 2022; revised manuscript received 09 August 2022; published online 25 August 2022
Citation B.V. Lopushanska, Y.M. Azhniuk, I.P. Studenyak, et al., J. Nano- Electron. Phys. 14 No 4, 04010 (2022)
DOI https://doi.org/10.21272/jnep.14(4).04010
PACS Number(s) 78.67.Hc
Keywords Quantum dots (3) , Colloidal synthesis, Absorption (17) , Photoluminescence (17) , Raman spectroscopy (18) .

Colloidal AgInS2 quantum dots (QDs) with intense broadband photoluminescence (PL) were synthesized in aqueous solutions in the presence of glutathione at mild conditions. Size-selective fractioning of QDs was performed by repeated centrifugation of the colloidal solution with the addition of 2-propanol. Based on the optical absorption and PL data, the dependences of the band gap and the PL maximum position on the QD size are analyzed. The Raman spectra of AgInS2 QDs exhibit only a slight variation with decreasing QD size explained by phonon confinement. Changes in the Raman spectra with increasing laser power density are most likely related to photoinduced oxidation of the AgInS2 QD surface with the formation of S–O bonds.

List of References