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Shape control of CdSe nanocrystals


Nanometre-size inorganic dots, tubes and wires exhibit a wide range of electrical and optical properties1,2 that depend sensitively on both size and shape3,4, and are of both fundamental and technological interest. In contrast to the syntheses of zero-dimensional systems, existing preparations of one-dimensional systems often yield networks of tubes or rods which are difficult to separate5,6,7,8,9,10,11,12. And, in the case of optically active II–VI and III–V semiconductors, the resulting rod diameters are too large to exhibit quantum confinement effects6,8,9,10. Thus, except for some metal nanocrystals13, there are no methods of preparation that yield soluble and monodisperse particles that are quantum-confined in two of their dimensions. For semiconductors, a benchmark preparation is the growth of nearly spherical II–VI and III–V nanocrystals by injection of precursor molecules into a hot surfactant14,15. Here we demonstrate that control of the growth kinetics of the II–VI semiconductor cadmium selenide can be used to vary the shapes of the resulting particles from a nearly spherical morphology to a rod-like one, with aspect ratios as large as ten to one. This method should be useful, not only for testing theories of quantum confinement, but also for obtaining particles with spectroscopic properties that could prove advantageous in biological labelling experiments16,17 and as chromophores in light-emitting diodes18,19.

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Figure 1: TEM images of different samples of quantum rods.
Figure 2: X-ray diffraction patterns of two CdSe rod-shaped nanocrystals.
Figure 3
Figure 4: Optical spectra and emission polarization of CdSe quantum dots and rods.

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  1. Heath, J. M. (ed.) Acc. Chem. Res. 32 (Nanoscale materials special issue) (1999).

  2. Alivisatos, A. P. Semiconductor clusters, nanocrystals, and quantum dots. Science 271, 933–937 ( 1996).

    Article  ADS  CAS  Google Scholar 

  3. Lieber, C. M. One-dimensional nanostructures: Chemistry, physics + applications. Solid State Commun. 107, 607–616 (1998).

    Article  ADS  CAS  Google Scholar 

  4. Smalley, R. E. & Yakobson, B. I. The future of the fullerenes. Solid State Commun. 107, 597– 606 (1998).

    Article  ADS  CAS  Google Scholar 

  5. Hu, J. T., Min, O. Y., Yang, P. D. & Lieber, C. M. Controlled growth and electrical properties of heterojunctions of carbon nanotubes and silicon nanowires. Nature 399, 48– 51 (1999).

    Article  ADS  CAS  Google Scholar 

  6. Wang, W. Z. et al. Synthesis and characterization of MSe (M = Zn, Cd) nanorods by a new solvothermal method. Inorg. Chem. Commun. 2, 83–85 (1999).

    Article  CAS  Google Scholar 

  7. Zhu, Y., Cheng, G. S. & Zhang, L. D. Preparation and formation mechanism of silicon nanorods. J. Mater. Sci. Lett. 17, 1897– 1898 (1998).

    Article  CAS  Google Scholar 

  8. Han, W. Q., Fan, S. S., Li, Q. Q. & Hu, Y. D. Synthesis of gallium nitride nanorods through a carbon nanotube-confined reaction. Science 277, 1287–1289 ( 1997).

    Article  CAS  Google Scholar 

  9. Routkevitch, D., Bigioni, T., Moskovits, M. & Xu, J. M. Electrochemical fabrication of cds nanowire arrays in porous anodic aluminum oxide templates. J. Phys. Chem. 100, 14037 –14047 (1996).

    Article  CAS  Google Scholar 

  10. Trentler, T. J. et al. Solution-liquid-solid growth of crystalline III-V semiconductors - an analogy to vapor-liquid-solid growth. Science 270, 1791–1794 (1995).

    Article  ADS  CAS  Google Scholar 

  11. Nishizawa, M., Menon, V. P. & Martin, C. R. Metal nanotubule membranes with electrochemically switchable ion-transport selectivity. Science 268, 700–702 (1995).

    Article  ADS  CAS  Google Scholar 

  12. Heath, J. R. A liquid-solution-phase synthesis of crystalline silicon. Science 258, 1131–1133 ( 1992).

    Article  ADS  CAS  Google Scholar 

  13. Ahmadi, T. S., Wang, Z. L., Green, T. C., Henglein, A. & El-Sayed, M. A. Shape-controlled synthesis of colloidal platinum nanoparticles. Science 272, 1924–1926 (1996).

    Article  ADS  CAS  Google Scholar 

  14. Peng, X. G., Wickham, J. & Alivisatos, A. P. Kinetics of II-VI and III-V colloidal semiconductor nanocrystal growth: “Focusing” of size distributions. J. Am. Chem. Soc. 120, 5343–5344 (1998).

    Article  CAS  Google Scholar 

  15. Murray, C. B., Norris, D. J. & Bawendi, M. G. Synthesis and characterization of nearly monodisperse CdE (E = S, Se, Te) semiconductor nanocrystallites. J. Am. Chem. Soc. 115, 8706–8715 ( 1993).

    Article  CAS  Google Scholar 

  16. Bruchez, M., Moronne, M., Gin, P., Weiss, S. & Alivisatos, A. P. Semiconductor nanocrystals as fluorescent biological labels. Science 281, 2013– 2016 (1998).

    Article  ADS  CAS  Google Scholar 

  17. Chan, W. C. W. & Nie, S. M. Quantum dot bioconjugates for ultrasensitive nonisotopic detection. Science 281 , 2016–2018 (1998).

    Article  ADS  CAS  Google Scholar 

  18. Schlamp, M. C., Peng, X. G. & Alivisatos, A. P. Improved efficiencies in light emitting diodes made with CdSe(CdS) core/shell type nanocrystals and a semiconducting polymer. J. Appl. Phys. 82, 5837– 5842 (1997).

    Article  ADS  CAS  Google Scholar 

  19. Mattoussi, H. et al. Electroluminescence from heterostructures of poly(phenylene vinylene) and inorganic CdSe nanocrystals. J. Appl. P. 83, 7965–7974 (1998).

    Article  ADS  CAS  Google Scholar 

  20. Kolosky, M. & Vialle, J. Determination of trioctylphosphine oxide and its impurities by reversed-phase high performance liquid chromatography. J. Chromatogr. 299, 436– 444 (1984).

    Article  CAS  Google Scholar 

  21. Cortina, J. L., Miralles, N., Aguilar, M. & Sastre, A. M. Distribution studies of Zn(II), Cu(II) and Cd(II) with Levextrel resins containing di(2,4,4-trimethylpentyl) phosphinic acid (Lewatit TP807’84). Hydrometallurgy 40, 195–206 (1996).

    Article  CAS  Google Scholar 

  22. Kabay, N. et al. Removal of metal pollutants (Cd(II) and Cr(III)) from phosphoric acid solutions by chelating resins containing phosphonic or diphosphonic groups. Ind. Eng. Chem. Res. 37, 2541– 2547 (1998).

    Article  CAS  Google Scholar 

  23. Huynh, W., Peng, X. & Alivisatos, A. P. CdSe nanocrystal rods/poly(3-hexylthiophene) composite photovoltaic devices. Adv. Mater. 11, 923 –927 (1999).

    Article  CAS  Google Scholar 

  24. Zunger, A. Electronic-structure theory of semiconductor quantum dots. Mater. Res. Bull. 23, 35–42 ( 1998).

    Article  CAS  Google Scholar 

  25. Leung, K., Pokrant, S. & Whaley, K. B. Exciton fine structure in CdSe nanoclusters. Physical Rev. B 57, 12291–12301 (1998).

    Article  ADS  CAS  Google Scholar 

  26. Efros, A. L. et al. Band-edge exciton in quantum dots of semiconductors with a degenerate valence band - dark and bright exciton states. Phys. Rev. B 54, 4843–4856 ( 1996).

    Article  ADS  CAS  Google Scholar 

  27. Nirmal, M. et al. Observation of the dark exciton in CdSe quantum dots. Phys. Rev. Lett. 75, 3728–3731 (1995).

    Article  ADS  CAS  Google Scholar 

  28. Empedocles, S. A., Neuhauser, R. & Bawendi, M. G. Three-dimensional orientation measurements of symmetric single chromophores using polarization microscopy. Nature 399, 126–130 (1999).

    Article  ADS  CAS  Google Scholar 

  29. Peng, X. G., Schlamp, M. C., Kadavanich, A. V. & Alivisatos, A. P. Epitaxial growth of highly luminescent CdSe/CdS core/shell nanocrystals with photostability and electronic accessibility. J. Am. Chem. Soc. 119, 7019–7029 ( 1997).

    Article  CAS  Google Scholar 

  30. Dabbousi, B. O. et al. (CdSe)ZnS core-shell quantum dots: Synthesis and characterization of a size series of highly luminescent nanocrystallites. J. Phys. Chem. B 101, 9463–9475 ( 1997).

    Article  CAS  Google Scholar 

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This work was supported by the US Department of Energy and by the National Renewable Energy Laboratory.

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Peng, X., Manna, L., Yang, W. et al. Shape control of CdSe nanocrystals. Nature 404, 59–61 (2000).

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