[1] [1] Iijima S. Nature, 1991, 354: 56.

[3] [3] Chen C S, Chen X H, Xu L S, et al. Carbon, 2005, 43(8): 1660.

[4] [4] Hou P X, Yang Q H, Bai S. J. Phys. Chem. B, 2002, 106(5): 963.

[5] [5] Chen C S, Chen X H, Yi B, et al. Acta Materialia, 2006, 54: 5401.

[6] [6] Ma R Z, Liang J, Xu C L. J. Power Sources, 1999, 84: 126.

[7] [7] Liu X M, Fu S Y, Xiao H M, et al. J. Solid State Chem., 2005, 178(9): 2798.

[8] [8] Ngo A T, Pileni M P. J. Appl. Phys., 2002, 92: 4649.

[9] [9] Ni Y H, Ge X W, Zhang Z C. Chem. Mater., 2002, 14: 14.

[10] [10] Fu Y, Wang R, Xu J, et al. Chem. Phys. Lett., 2003, 379: 373.

[11] [11] Lian S, Wang E, Kang Z, et al. Solid State Commun., 2004, 129(8): 485.

[12] [12] Zhu L P, Xiao H M, Liu X M, et al. J. Material. Chem., 2006, 16(19): 1794.

[13] [13] Li L L, Chu Y, Liu Y. Nanotechnology, 2007, 18: 105603.

[14] [14] Saric A, Music S, Nomura K, et al. Mater. Sci. Engineering (B), 1998, 56: 43.

[15] [15] Cornell R M, Schwertmann U. The Iron Oxides: Structure, Properties, Reactions, Occurrence and Uses. New York: VCH Publishers, 1996. 395.

[16] [16] Fariad L A, Venancio S S, Oliveira M T. J. Raman Spectrosc., 1997, 28: 873.

[17] [17] Zawadzki M, Wrzyszcz J. Materials Research Bulletin, 2000, 35: 109.

[18] [18] Wu Z Y, Gota S, Jollet F, et al. Phys. Rev. B, 1997, 55: 2570.

[19] [19] Groot F M F, Grioni M, Fuggle J C, et al. Phys. Rev. B, 1989, 40: 5715.

[20] [20] Guiot E, Wu Z Y, Gota S. J. Electron Spec. and Related Phenomena, 1999, 101-103: 371.