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利用正电子湮没技术研究了10 at.% Co掺杂的Co3O4/ZnO纳米复合物中退火对缺陷的影响. 利用X射线衍射(XRD)测量了Co3O4/ZnO纳米复合物的结构和晶粒尺寸. 随着退火温度升高,Co3O4相逐步消失,ZnO晶粒尺寸也有显著增加. 经过1000 ℃以上退火后,Co3O4相完全消失,并出现了CoO的岩盐结构. 正电子湮没寿命测量显示出Co3O4 /ZnO纳米复合物中存在大量的Zn空位和空位团. 这些空位缺陷可能存在于纳米复合物的界面区域. 当退火温度达到700 ℃后Zn空位开始恢复,空位团也开始收缩. 900 ℃以上退火后,所有空位缺陷基本消失,正电子寿命接近ZnO完整晶格中的体态寿命值. 符合多普勒展宽谱测量也显示Co3O4 /ZnO纳米复合物经过900 ℃以上退火后电子动量分布与单晶ZnO基本一致,表明界面缺陷经过退火后得到消除.ZnO nanopowders are mechanically mixed with a certain quantity of Co3O4 nanopowders to obtain 10at.% Co doped Co3O4/ZnO composites. The nanocomposites are annealed in argon atmosphere at different temperatures between 100 ℃ and 1200 ℃. The structure and the grain size of the nanocomposite are investigated by X-ray diffraction 2 scans. With annealing temperature increasing up to 700 ℃, Co3O4 phase gradually disappears, and ZnO grain size begins to increase significantly. After annealing at above 1000 ℃, Co3O4 phase completely disappears, and CoO phase (rock-salt crystal structure) appears. Positron annihilation lifetime measurements reveal a large number of Zn vacancies and vacancy clusters existing in the interface region of the Co3O4 /ZnO nanocomposites. These defects are gradually recovered after annealing at above 700 ℃, and their number is under the detection limit after annealing at 900 ℃. The same conclusion can be drawn from the coincidence Doppler broadening (CDB) measurements.
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Keywords:
- ZnO /
- nanocomposites /
- interface defects
[1] Chambers S A 2002 Mater. Today 5 34
[2] Punnoose, Reddy K M, Hays J, Thurber A, Engelhard M H 2006 Appl. Phys. Lett. 89 112509
[3] [4] [5] Dietl T, Ohno H, Matsukura F, Cibert J, Ferrand D 2000 Science 287 1019
[6] Goodenough J B 1976 Magnetism and the chemical bond (New York-London: R E Krieger)
[7] [8] [9] Kim K Y, Yoon M, Park I W, Park Y J, Lyou J H 2004 Solid State Communications 129 175
[10] Reynolds D C,Collins T C 1969 Phys. Rev. 185 1099
[11] [12] Park Y S, Litton C W, Collins T C, Reynolds D C 1965 Phys. Rev. 143 512
[13] [14] Xu Q Y, Schmidt H, Hartmann L, Hochmuth H, Lorenz M, Setzer A, Esquinazi P, Meinecke C, Grundmann M 2007 Appl. Phys. Lett. 91 092503
[15] [16] [17] Fukuma Y, Odawara F, Asada H, Koyanagi T 2008 Phys. Rev. B 78 104417
[18] Li X L, Xu X H, Quan Z Y, Guo Z F, Wu H S, Gehring G A 2009 J. Appl. Phys. 105 103914
[19] [20] Sundaresan A, Rao C N R 2009 Nano Today 4 96
[21] [22] Kapilashrami M, Xu J, Strm V, Rao K V, Belova L 2009 Appl. Phys. Lett. 95 033104
[23] [24] Mal S, Nori S, Jin C M, Narayan J, Nellutla S, Smirnov A I, Prater J T 2010 J. Appl. Phys. 108 073510
[25] [26] [27] Chen Z Q, Yamamoto S, Maekawa M, Kawasuso A, Yuan X L, Sekiguchi T 2003 J. Appl. Phys. 94 4807
[28] Chen Z Q, Wang S J, Maekawa M, Kawasuso A, Naramoto H, Yuan X L, Sekiguchi T 2007 Phys. Rev. B 75 245206
[29] [30] [31] Tuomisto F, Ranki V, Saarinen K, Look D C 2003 Phys. Rev. Lett. 91 205502
[32] [33] Chen Z Q, Maekawa M, Yamamoto S, Kawasuso A, Yuan X L, Sekiguchi T, Suzuki R, Ohdaira T 2004 Phys. Rev. B 69 035210.
[34] Peng C X, Wang K F, Zhang Y, Guo F L, Weng H M, Ye B J 2009 Chin. Phys. B 18 2072
[35] [36] Quesada A, Garcia M A, Andres M, Hernando, A, Fernandez J F, CaballeroA C, Martin-Gonzalez M S, Briones F 2006 Journal of Applied Physic 100 113909
[37] [38] Wang D, Chen Z Q, Wang D D, Qi N, Gong J, Cao C Y, Tang Z 2010 J. Appl. Phys. 107 023524
[39] [40] Uedono A, Koida T, Tsukazaki A, Kawasaki M, Chen Z Q, Chichibu C F, Koinuma H 2003 J. Appl. Phys. 93 2481
[41] [42] Zubiaga A, Tuomisto F, Plazaola F, Saarinen K, Garcia J A,Rommeluere J F, Zuniga-Perez J, Munoz-Sanjose V 2005 Appl. Phys. Lett. 86 042103
[43] -
[1] Chambers S A 2002 Mater. Today 5 34
[2] Punnoose, Reddy K M, Hays J, Thurber A, Engelhard M H 2006 Appl. Phys. Lett. 89 112509
[3] [4] [5] Dietl T, Ohno H, Matsukura F, Cibert J, Ferrand D 2000 Science 287 1019
[6] Goodenough J B 1976 Magnetism and the chemical bond (New York-London: R E Krieger)
[7] [8] [9] Kim K Y, Yoon M, Park I W, Park Y J, Lyou J H 2004 Solid State Communications 129 175
[10] Reynolds D C,Collins T C 1969 Phys. Rev. 185 1099
[11] [12] Park Y S, Litton C W, Collins T C, Reynolds D C 1965 Phys. Rev. 143 512
[13] [14] Xu Q Y, Schmidt H, Hartmann L, Hochmuth H, Lorenz M, Setzer A, Esquinazi P, Meinecke C, Grundmann M 2007 Appl. Phys. Lett. 91 092503
[15] [16] [17] Fukuma Y, Odawara F, Asada H, Koyanagi T 2008 Phys. Rev. B 78 104417
[18] Li X L, Xu X H, Quan Z Y, Guo Z F, Wu H S, Gehring G A 2009 J. Appl. Phys. 105 103914
[19] [20] Sundaresan A, Rao C N R 2009 Nano Today 4 96
[21] [22] Kapilashrami M, Xu J, Strm V, Rao K V, Belova L 2009 Appl. Phys. Lett. 95 033104
[23] [24] Mal S, Nori S, Jin C M, Narayan J, Nellutla S, Smirnov A I, Prater J T 2010 J. Appl. Phys. 108 073510
[25] [26] [27] Chen Z Q, Yamamoto S, Maekawa M, Kawasuso A, Yuan X L, Sekiguchi T 2003 J. Appl. Phys. 94 4807
[28] Chen Z Q, Wang S J, Maekawa M, Kawasuso A, Naramoto H, Yuan X L, Sekiguchi T 2007 Phys. Rev. B 75 245206
[29] [30] [31] Tuomisto F, Ranki V, Saarinen K, Look D C 2003 Phys. Rev. Lett. 91 205502
[32] [33] Chen Z Q, Maekawa M, Yamamoto S, Kawasuso A, Yuan X L, Sekiguchi T, Suzuki R, Ohdaira T 2004 Phys. Rev. B 69 035210.
[34] Peng C X, Wang K F, Zhang Y, Guo F L, Weng H M, Ye B J 2009 Chin. Phys. B 18 2072
[35] [36] Quesada A, Garcia M A, Andres M, Hernando, A, Fernandez J F, CaballeroA C, Martin-Gonzalez M S, Briones F 2006 Journal of Applied Physic 100 113909
[37] [38] Wang D, Chen Z Q, Wang D D, Qi N, Gong J, Cao C Y, Tang Z 2010 J. Appl. Phys. 107 023524
[39] [40] Uedono A, Koida T, Tsukazaki A, Kawasaki M, Chen Z Q, Chichibu C F, Koinuma H 2003 J. Appl. Phys. 93 2481
[41] [42] Zubiaga A, Tuomisto F, Plazaola F, Saarinen K, Garcia J A,Rommeluere J F, Zuniga-Perez J, Munoz-Sanjose V 2005 Appl. Phys. Lett. 86 042103
[43]
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