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Variation in the structural and optical properties of ZnSe/ZnS core/shell nanocrystals with shell thickness

  • Yun-Mo Sung
  • Minkyou You
  • Tae Geun Kim
Research Paper

Abstract

ZnSe/ZnS nanocrystals were synthesized using the TOP/TOPO mild chemistry approach. Shell thickness was varied by changing the shell precursor concentration. Corresponding structural variation was investigated monitoring X-ray diffraction peak shifts. High-resolution transmission electron microscopy images revealed that ZnSe/ZnS nanocrystals with thick shell have crystalline imperfections such as stacking faults due to the heavy compressive strain by ZnS shell. The red- and blue-shifts in photoluminescence (PL) spectra according to the shell thickness were identified to originate from the extension of electron wave function of ZnSe to the shell and the compressive strain of the core, respectively. The PL spectra also showed increase and decrease in the peak intensity with shell thickness due to the surface passivation effect and stacking faults, respectively.

Keywords

ZnSe/ZnS Core/shell Nanocrystals Photoluminescence (PL) Shell thickness 

Notes

Acknowledgments

This work was supported by the National Research Foundation of Korea (NRF) grants funded by the Korean Government (2011-0002789; 2011-0011205) and by the International Collaborative R&D Program (2011-BS-101002-002) funded by Ministry of Knowledge Economy, Korea (MKE, Korea) in 2011. Also, this work was supported by Korea University grants (2010) (Y.-M. Sung). This work was supported by the National Research Foundation of Korea (NRF) grants funded by the Korean Government (MEST) (2011-0028769) (T. G. Kim).

References

  1. Alivisatos AP (1996) Perspectives on the physical chemistry of semiconductor naanocrystals. J Phys Chem 100:13226–13239CrossRefGoogle Scholar
  2. Chang JY, Kim TG, Sung YM (2011) Synergistic effects of SPR and FRET on the photoluminescence of ZnO nanorod heterostructures. Nanotechnology 22:425708CrossRefGoogle Scholar
  3. Chen HS, Wang SJJ, Lo CJ, Chi JY (2005) White-light emission from organics-capped ZnSe quantum dots and application in white-light emitting diodes. Appl Phys Lett 86:131905CrossRefGoogle Scholar
  4. Cullity BD, Stock SR (2001) Elements of X-ray diffraction, 3rd edn. Prentice Hall, Upper Saddle River, NJGoogle Scholar
  5. Dabbousi BO, Rodriguez-Viejo J, Mikulec FV, Heine JR, Mattoussi H, Ober R, Jensen KF, Bawendi MG (1997) (CdSe)ZnS core-shell quantum dots: synthesis and characterization of a size series of highly luminescent nanocrystallites. J Phys Chem B 101:9463–9475CrossRefGoogle Scholar
  6. Danek M, Jensen KF, Murray CB, Bawendi MG (1996) Synthesis of luminescent thin-film CdSe/ZnSe quantum dot composites using CdSe quantum dots passivated with an overlayer of ZnSe. Chem Mater 8:173–180CrossRefGoogle Scholar
  7. Hines MA, Guyot-Sionnest P (1998) Bright UV-blue luminescent colloidal ZnSe nanocrystals. J Phys Chem B 102:3655–3657CrossRefGoogle Scholar
  8. Isnaeni Kim KH, Nguyen DL, Lim H, Nga PT, Cho YH (2011) Shell layer dependence of photoblinking in CdSe/ZnSe/ZnS quantum dots. Appl Phys Lett 98:012109CrossRefGoogle Scholar
  9. Lad AD, Mahamuni (2008) Effect of ZnS shell formation on the confined energy levels of ZnSe quantum dots. Phys Rev B 78:125421CrossRefGoogle Scholar
  10. Lee YJ, Kim TG, Sung YM (2006) Lattice distortion and luminescence of CdSe/ZnSe nanocrystals. Nanotechnol 17:3539–3542CrossRefGoogle Scholar
  11. Lee MK, Kim TG, Kim W, Sung YM (2008a) Surface plasmon resonance (SPR) electron and energy transfer in noble metal-zinc oxide composite nanocrystals. J Phys Chem C 112:10079–10082CrossRefGoogle Scholar
  12. Lee W, Kwak WC, Min SK, Lee JC, Chae WS, Sung YM, Han SH (2008b) Spectral broadening in quantum dots-sensitized photoelectrochemical solar cells based on CdSe and Mg-doped CdSe nanocrystals. Electrochem Commun 10:1699–1702CrossRefGoogle Scholar
  13. Liu Y, Qiu HY, Xu Y, Wu D, Li MJ, Jiang JZ, Lai GQ (2007) Selective synthesis of wurtzite CdSe nanorods and zinc blend CdSe nanocrystals through a convenient solvothermal route. J Nanopart Res 9:745–752CrossRefGoogle Scholar
  14. Mattoussi H, Mauro JM, Goldman ER, Anderson GP, Sundar VC, Mikulec FV, Bawendi MG (2000) Self-assembly of CdSe-ZnS quantum dot bioconjugats using an engineered recombinant protein. J Am Chem Soc 122:12142–12150CrossRefGoogle Scholar
  15. Milliron DJ, Alivisatos AP, Pitois C, Edder C, Frechet JMJ (2003) Electroactive surfactant designed to medicate electron transfer between CdSe nanocrystals and organic semiconductors. Adv Mater 15:58–61CrossRefGoogle Scholar
  16. Murray CB, Norris DJ, Bawendi MG (1993) Synthesis and characterization of nearly monodispersed CdE (E = S, Se, Te) semiconductor nanocrystallites. J Am Chem Soc 115:8706–8715CrossRefGoogle Scholar
  17. Patrick TK, Stouwdam JW, Janssen AJ (2009) Highly luminescent ultranarrow Mn doped ZnSe nanowires. Nano Lett 9:745–750CrossRefGoogle Scholar
  18. Peng ZA, Peng XG (2001) Formation of high-quality CdTe, CdSe, and CdS nanocrystals using CdO as precursor. J Am Chem Soc 123:183–184CrossRefGoogle Scholar
  19. Peng ZA, Peng XG (2002) Nearly monodisperse and shape-controlled CdSe nanocrystals via alternative routes: nucleation and growth. J Am Chem Soc 124:3343–3353CrossRefGoogle Scholar
  20. Peng XG, Schlamp MC, Kadavanich AV, Alivisatos AP (1997) Epitaxial growth of highly luminescent CdSe/CdS core/shell nanocrystals with photostability and electronic accessibility. J Am Chem Soc 119:7019–7029CrossRefGoogle Scholar
  21. Reiss P, Bleuse J, Pron A (2002) Highly luminescent CdSe/ZnSe core/shell nanocrystals of low size dispersion. Nano Lett 2:781–784CrossRefGoogle Scholar
  22. Sen P, Chattopadhyay, Andrews JT, Sen PK (2010) Impact of shell thickness on exciton and biexciton binding energy of a ZnSe/ZnS core-shell quantum dot. J Phys Chem Sol 71:1201–1205CrossRefGoogle Scholar
  23. Shim M, Guyot-Sionnest P (2000) N-type colloidal semiconductor nanocrystals. Nature 407:981–983CrossRefGoogle Scholar
  24. Steckel JS, Coe-Sullivan S, Bulovic V, Bawendi MG (2003) 1.3 μm to 1.55 μm tunable electroluminescence from PbSe quantum dots embedded within an organic device. Adv Mater 15:1862–1866CrossRefGoogle Scholar
  25. Sung YM, Lee YJ, Park KS (2006) Kinetic analysis for formation of Cd1−xZnxSe solid-solution nanocrystals. J Am Chem Soc 128:9002–9003CrossRefGoogle Scholar
  26. Watson S, Beydoun D, Scott J, Amal R (2004) Preparation of nanosized crystalline TiO2 particles at low temperature for photocatalysis. J Nanopart Res 6:193–207CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Department of Materials Science & EngineeringKorea UniversitySeoulSouth Korea
  2. 2.Department of Electronic EngineeringKorea UniversitySeoulSouth Korea

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