Synthesis of Highly Monodisperse CdSe Quantum Dots and Size Dependency of Optical Properties

Abstract

Semiconductor quantum dots have wide application areas as they have unique electrical and optical properties. In recent years, CdSe quantum dots are one of the most preferred nanomaterials. Highly monodisperse zinc blend CdSe quantum dots were synthesized using hot injection method. The structure and optical properties of the samples were determined by UV-Vis, photoluminescence, XRD and TEM methods. As a result, the difference between 2S-1P absorption transitions did not change with particle size. However, the difference between 1S-2S and 1S-1P transitions were found to be inversely proportional to particle size.  The FWHM value of the photoluminescence spectrum of the smallest sample has decreased to 25 mm and Stokes shifts were observed to be 0.06 eV.

Keywords

• CdSe,Quantum Dot,hot injection,optical absorption,photoluminescence,nanotechnology

Yüksek Oranda Eş Parçacık Boyutlu CdSe Kuantum Noktaların Sentezi ve Optiksel Özelliklerinin Parçacık Boyutlarına Bağlılığı

Abstract

Benzersiz elektriksel ve optik özelliklerinden dolayı yarıiletken kuantum noktalar birçok uygulama alanına sahiptirler. Son yıllarda CdSe kuantum noktalar en fazla tercih edilen nanomalzemelerin başında yer almaktadır. Sıcak enjeksiyon metodunu kullanarak yüksek oranda eş parçacık boyutuna sahip ve altıgen tip bir simetriye sahip çinko blend kristal tipinde CdSe kuantum noktalar sentezlendi. Elde edilen numunelerin yapıları ve özellikleri UV-Vis, fotolüminesans, XRD ve TEM karakterizasyon metodlarıyla aydınlatıldı. 1S, 2S ve 1P absorbsiyon geçişleri ve Stoke kayma miktarlarının malzeme boyutlarıyla olan ilişkileri incelendi.

Keywords

• CdSe,Kuantum nokta,sıcak enjeksiyon,optik soğurma,fotolüminesans,nanoteknoloji

References

1. [1] A. J. Nozik, M. C. Beard, J. M. Luther, M. Law, R. J. Ellingson, and J. C. Johnson, ‘Semiconductor quantum dots and quantum dot arrays and applications of multiple exciton generation to third-generation photovoltaic solar cells’, Chem. Rev., vol. 110, no. 11, pp. 6873–6890, 2010.
2. [2] E. Elibol, P. S. Elibol, M. Cadırcı, and N. Tutkun, ‘Improving the performance of CdTe QDSSCs by chloride treatment and parameter optimization’, Mater. Sci. Semicond. Process., vol. 96, pp. 30–40, Jun. 2019.
3. [3] S. A. Mcdonald et al., ‘Solution-processed PbS quantum dot infrared photodetectors and photovoltaics’, Nat. Mater., vol. 4, no. 2, pp. 138–142, Feb. 2005.
4. [4] V. Sukhovatkin, S. Hinds, L. Brzozowski, and E. H. Sargent, ‘Colloidal Quantum-Dot Photodetectors Exploiting Multiexciton Generation’, Science (80-. )., vol. 324, no. 5934, pp. 1542–1544, 2009.
5. [5] Y. Yang et al., ‘High-efficiency light-emitting devices based on quantum dots with tailored nanostructures’, Nat. Photonics, vol. 9, no. 4, pp. 259–265, Apr. 2015.
6. [6] S. Zhu et al., ‘Strongly green-photoluminescent graphene quantum dots for bioimaging applications’, Chem. Commun., vol. 47, no. 24, pp. 6858–6860, Jun. 2011.
7. [7] N. Shukla and M. M. Nigra, ‘Synthesis of CdSe quantum dots with luminescence in the violet region of the solar spectrum’, Luminescence, vol. 25, no. 1, pp. 14–18, 2010.
8. [8] J. Park, J. Joo, G. K. Soon, Y. Jang, and T. Hyeon, ‘Synthesis of monodisperse spherical nanocrystals’, Angewandte Chemie - International Edition, vol. 46, no. 25. John Wiley & Sons, Ltd, pp. 4630–4660, 18-Jun-2007.

9. [9] Y. Yin and A. P. Alivisatos, ‘Colloidal nanocrystal synthesis and the organic-inorganic interface’, Nature, vol. 437, no. 7059. Nature Publishing Group, pp. 664–670, 28-Sep-2005.
10. [10] M. Bawendi, ‘The Quantum Mechanics Of Larger Semiconductor Clusters (’, Annu. Rev. Phys. Chem., vol. 41, no. 1, pp. 477–496, Oct. 1990.
11. [11] M. B. Mohamed, D. Tonti, A. Al-Salman, A. Chemseddine, and M. Chergui, ‘Synthesis of high quality zinc blende CdSe nanocrystals.’, J. Phys. Chem. B, vol. 109, no. 21, pp. 10533–7, 2005.
12. [12] J. Park, J. Joo, G. K. Soon, Y. Jang, and T. Hyeon, ‘Synthesis of monodisperse spherical nanocrystals’, Angew. Chemie - Int. Ed., vol. 46, no. 25, pp. 4630–4660, 2007.
13. [13] Victor I. Klimov, ‘Nanocrystal Quantum Dots’, in CRC Press Taylor & Francis Group, 2nd ed., Victor I. Klimov, Ed. Boca Raton London New York: CRC Press Taylor & Francis Group, 2010, pp. 147–213.
14. [14] W. W. Yu, L. Qu, W. Guo, and X. Peng, ‘Experimental Determination of the Extinction Coefficient of CdTe, CdSe, and CdS Nanocrystals’, Chem. Mater., vol. 15, no. 14, pp. 2854–2860, Jul. 2003.
15. [15] A. M. Nightingale and J. C. Demello, ‘Improving the ensemble optical properties of InP quantum dots by indium precursor modification’, J. Mater. Chem. C, vol. 4, no. 36, pp. 8454–8458, 2016.
16. [16] A. Saha, K. V. Chellappan, K. S. Narayan, J. Ghatak, R. Datta, and R. Viswanatha, ‘Near-unity quantum yield in semiconducting nanostructures: Structural understanding leading to energy efficient applications’, J. Phys. Chem. Lett., vol. 4, no. 20, pp. 3544–3549, Oct. 2013.
17. [17] D. Norris and M. Bawendi, ‘Measurement and assignment of the size-dependent optical spectrum in CdSe quantum dots’, Phys. Rev. B - Condens. Matter Mater. Phys., vol. 53, no. 24, pp. 16338–16346, Jun. 1996.
18. [18] C. B. Murray, D. J. Norris, and M. G. Bawendi, ‘Synthesis and Characterization of Nearly Monodisperse CdE (E = S, Se, Te) Semiconductor Nanocrystallites’, J. Am. Chem. Soc., vol. 115, no. 19, pp. 8706–8715, Sep. 1993.