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Defects in three-dimensional spherical assemblies of Ni-doped ZnO nanocrystals

Published online by Cambridge University Press:  31 January 2011

K.C. Barick
Affiliation:
Department of Metallurgical Engineering & Materials Science, Indian Institute of Technology Bombay, Mumbai-400076, India
M. Aslam
Affiliation:
Department of Physics, Indian Institute of Technology Bombay, Mumbai-400076, India
Vinayak P. Dravid*
Affiliation:
Department of Materials Science & Engineering, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208
D. Bahadur*
Affiliation:
Department of Metallurgical Engineering & Materials Science, Indian Institute of Technology Bombay, Mumbai-400076, India
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Abstract

Three-dimensional spherical assemblies of Ni-doped ZnO nanocrystals have been prepared by the solution phase synthesis process. It has been observed that transition metal ions (Zn, Ni) are uniformly distributed in the sample and exist in the +2 oxidation state. Detailed investigation of structural defects formed during the formation of spherical assemblies by oriented attachment of nanocrystals was carried out by high-resolution transmission electron microscope (HRTEM), Raman and photoluminescence (PL) spectroscopy. HRTEM analysis revealed the existence of various crystal defects, such as stacking faults, dislocations, etc. The incorporation of Ni2+ into ZnO structure strongly influences the vibrational and optical properties of the sample due to the increment of defect densities. Compared to the optical phonons of ZnO, additional mode observed at 538 cm−1 in Raman spectra of Ni-doped ZnO could be associated with the incorporation of Ni2+ in Zn2+ site. The increase in PL intensity of green emission with Ni2+ doping indicates the formation of a higher concentration of oxygen vacancy in doped nanostructures.

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Articles
Copyright
Copyright © Materials Research Society 2009

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References

REFERENCES

1.Wu, L.Y.L., Tok, A.I.Y., Boey, F.Y.C., Zeng, X.T., and Zhang, X.H.: Chemical synthesis of ZnO nanocrystals. IEEE Trans. Nanotechnol. 6, 497 (2007).Google Scholar
2.Shen, L., Bao, N., Yanagisawa, K., Domen, K., Gupta, A., and Grimes, C. A.: Direct synthesis of ZnO nanoparticles by a solution-free mechanochemical reaction. Nanotechnol. 17, 5117 (2006).Google Scholar
3.Srikant, V. and Clarke, D.R.: On the optical band gap of zinc oxide. J. Appl. Phys. 83, 5447 (1998).CrossRefGoogle Scholar
4.Bauer, C., Boschloo, G., Mukhtar, E., and Hagfeldt, A.: Electron injection and recombination in Ru(dcbpy)2(NCS)2 sensitized nanostructured ZnO. J. Phys. Chem. B 105, 5585 (2001).Google Scholar
5.Ohno, H.: Making nonmagnetic semiconductors ferromagnetic. Science 281, 951 (1998).Google Scholar
6.Sharma, P., Gupta, A., Rao, K.V., Owens, F.J., Sharma, R., Ahuja, R., Guillen, J.M.O., Johansson, B., and Gehring, G.A.: Fer-romagnetism above room temperature in bulk and transparent thin films of Mn-doped ZnO. Nat. Mater. 2, 673 (2003).CrossRefGoogle ScholarPubMed
7.Wu, D., Yang, M., Huang, Z., Yin, G., Liao, X., Kang, Y., Chen, X., and Wang, H.: Preparation and properties of Ni-doped ZnO rod arrays from aqueous solution. J. Colloid Interface Sci. 330, 380 (2009).CrossRefGoogle ScholarPubMed
8.Kaschner, A., Haboeck, U., Strassburg, M., Kaczmarczyk, G., Hoffmann, A., Thomsen, C., Zeuner, A., Alves, H.R., Hofmann, D.M., and Meyer, B.K.: Nitrogen-related local vibrational modes in ZnO. N. Appl. Phys. Lett. 80, 1909 (2002).CrossRefGoogle Scholar
9.Viswanatha, R., Sapra, S., Gupta, S.S., Satpati, B., Satyam, P.V., Dev, B.N., and Sarma, D.D.: Synthesis and characterization of Mn-doped ZnO nanocrystals. J. Phys. Chem. B 108, 6303 (2004).Google Scholar
10.Biegger, E., Fonin, M., Rüdiger, U., Janβen, N., Beyer, M., Thomay, T., Bratschitsch, R., and Dedkov, Y.S.: Defect induced low temperature ferromagnetism in Zn1−xCoxO films. J. Appl. Phys. 101, 073904 (2007).CrossRefGoogle Scholar
11.Hong, N.H., Sakai, J., Huong, N.T., Poirot, N., and Ruyter, A.: Role of defects in tuning ferromagnetism in diluted magnetic oxide thin films. Phys. Rev. B 72, 045336 (2005).Google Scholar
12.Kittilstved, K.R., Schwartz, D.A., Tuan, A.C., Heald, S.M., Chambers, S.A., and Gamelin, D.R.: Direct kinetic correlation of carriers and ferromagnetism in Co2+: ZnO. Phys. Rev. Lett. 97, 037203 (2006).Google Scholar
13.Liu, H., Zhang, X., Li, L., Wang, Y.X., Gao, K.H., Li, Z.Q., Zheng, R.K., Ringer, S.P., Zhang, B., and Zhang, X.X.: Role of point defects in room-temperature ferromagnetism of Cr-doped ZnO. Appl. Phys. Lett. 91, 072511 (2007).Google Scholar
14.Xing, G.Z., Yi, J.B., Tao, J.G., Liu, T., Wong, L.M., Zhang, Z., Li, G.P., Wang, S.J., Ding, J., Sum, T.C., Huan, C.H.A., and Wu, T.: Comparative study of structural inhomogeneity enhanced room-temperature ferromagnetism in Cu-doped ZnO nanowires. Adv. Mater. 20, 3521 (2008).CrossRefGoogle Scholar
15.Venkatesan, M., Fitzgerald, C.B., Lunney, J.G., and Coey, J.M.D.: Anisotropic ferromagnetism in substituted zinc oxide. Phys. Rev. Lett. 93, 177206 (2004).Google Scholar
16.Coey, J.M.D., Venkatesan, M., and Fitzgerald, C.B.: Donor impurity band exchange in dilute ferromagnetic oxides. Nat. Mater. 4, 173 (2005).CrossRefGoogle ScholarPubMed
17.Sundaresan, A., Bhargavi, R., Rangarajan, N., Siddesh, U., and Rao, C.N.R.: Ferromagnetism as a universal feature of nanoparticles of the otherwise nonmagnetic oxides. Phys. Rev. B 74, 161306 (2006).Google Scholar
18.Penn, R.L. and Banfield, J.F.: Imperfect oriented attachment: Dislocation generation in defect-free nanocrystals. Science 281, 969 (1998).CrossRefGoogle ScholarPubMed
19.Banfield, J.F., Welch, S.A., Zhang, H., Ebert, T.T., and Penn, R.L.: The role of aggregation in crystal growth and transformations in nano-phase FeOOH biomineralization products. Science 289, 751 (2000).Google Scholar
20.Barick, K.C., Aslam, M., Dravid, V.P., and Bahadur, D.: Self-aggregation and assembly of size-tunable transition metal doped ZnO nanocrystals. J. Phys. Chem. C 112, 15163 (2008).CrossRefGoogle Scholar
21.Barick, K.C. and Bahadur, D.: Synthesis, self-assembly and properties of Mn-doped ZnO nanoparticles. J. Nanosci. Nanotechnol. 7, 1935 (2007).Google Scholar
22.Yin, Z.G., Chen, N., Yang, F., Chai, S.L., Zhong, J., Qian, H.J., and Ibrahim, K.: Structural, magnetic properties and photoemission study of Ni-doped ZnO. Solid State Commun. 135, 430 (2005).Google Scholar
23. CWagner, D., Riggs, W.M., Davis, L.E., and Moulder, J.F.: Handbook of X-ray Photoelectron Spectroscopy (Perkin Elmer, Eden Prairie, MN, 1979), p. 81.Google Scholar
24.Yan, Y., Dalpian, G.M., Al-Jassim, M.M., and Wei, S.: Energetics and electronic structure of stacking faults in ZnO. Phys. Rev. B 70, 193206 (2004).Google Scholar
25.Yang, L.W., Wu, X.L., Huang, G.S., Qiu, T., and Yang, Y.M.: In situ synthesis of Mn-doped ZnO multileg nanostructures and Mn-related Raman vibration. J. Appl. Phys. 97, 014308 (2005).CrossRefGoogle Scholar
26.Wang, X., Xu, J., Zhang, B., Yu, H., Wang, J., Zhang, X., Yu, J., and Li, Q.: Signature of intrinsic high-temperature ferromagnetism in cobalt-doped zinc oxide nanocrystals. Adv. Mater. 18, 2476 (2006).Google Scholar
27.Phan, T.L., Vincent, R., Cherns, D., Nghia, N.X., and Ursaki, V.V.: Raman scattering in Me-doped ZnO nanorods (Me = Mn, Co, Cu, and Ni) prepared by thermal diffusion. Nanotechnol. 19, 475702 (2008).Google Scholar
28.Barick, K.C. and Bahadur, D.: Influence of Mn doping on structural and vibrational properties of self-assembled Mn-doped ZnO nanocrystals. J. Nanosci. Nanotechnol. 8, 4263 (2008).CrossRefGoogle ScholarPubMed
29.Bundesmann, C., Ashkenov, N., Schubert, M., Spemann, D., Butz, T., Kaidashev, E.M., Lorenz, M., and Grundmann, M.: Raman scattering in ZnO thin films doped with Fe, Sb, Al, Ga, and Li. Appl. Phys. Lett. 83, 1974 (2003).CrossRefGoogle Scholar
30.Sato-Berrú, R.Y., Vázquez-Olmos, A., Fernández-Osorio, A.L., and Sotres-martínez, S.: Micro-Raman investigation of transition-metal-doped ZnO nanoparticles. J. Raman Spectrosc. 38, 1073 (2007).CrossRefGoogle Scholar
31.Wu, J.J., Wen, H.I., Tseng, C.H., and Liu, S.C.: Well-aligned ZnO nanorods via hydrogen treatment of ZnO films. Adv. Funct. Mater. 14, 806 (2004).CrossRefGoogle Scholar
32.Kong, Y.C., Yu, D.P., Zhang, B., Fang, W., and Feng, S.Q.: Ultraviolet-emitting ZnO nanowires synthesized by a physical vapor deposition approach. Appl. Phys. Lett. 78, 407 (2001).Google Scholar
33.Norberg, N.S., Kittilstved, K.R., Amonette, J.E., Kukkadapu, R.K., Schwartz, D.A., and Gamelin, D.R.: Synthesis of colloidal Mn2+: ZnO quantum dots and high-T C ferromagnetic nanocrystalline thin films. J. Am. Chem. Soc. 126, 9387 (2004).Google Scholar
34.Parra-Palomino, A., Perales-Perez, O., Singhal, R., Tomar, M., Hwang, J., and Voyles, P. M.: Structural, optical, and magnetic characterization of monodisperse Fe-doped ZnO nanocrystals. J. Appl. Phys. 103, 07D121 (2008).Google Scholar