摘要
本论文主要利用同步辐射X射线吸收精细结构(XAFS),结合透射电镜(TEM)和X射线衍射(XRD)等实验方法研究三种纳米体系:(1)具有可控光电性能的Ⅱ-Ⅵ族CdSe半导体纳米晶;(2)具有室温铁磁性的过渡金属Co掺杂ZnO纳米晶;(3)具有电化学储氢性能的一维Se纳米管。在微观局域结构的基础上分别探讨了CdSe纳米晶的生长机理、Co掺杂ZnO纳米晶的结构特点和磁学性能以及Se纳米管的形成机理,从而为高性能半导体纳米晶发光材料、稀磁半导体纳米材料和电化学储氢纳米材料的可控制备提供理论的研究基础。
1.CdSe纳米晶熟化过程的结构演变研究
利用XAFS、XRD和高分辨透射电镜(HR-TEM)等方法研究CdSe半导体纳米晶熟化生长过程中的结构演化。利用尺寸选择分离的方法制备尺寸分别为1.9、2.7和3.1nm,且尺寸分布较窄(<10%)的纳米晶。XAFS结果表明,随着CdSe颗粒尺寸从1.9nm增加到2.7和3.1nm,其Se-Cd第一近邻配位的结构无序度σ_S~2从0.0005(?)增加到0.0012和0.0034(?)。1.9nm的CdSe颗粒具有很小的σ_S~2表明生长到该阶段的时候其结晶程度很好,内部缺陷很少。σ_S~2随着颗粒尺寸的增加而增加,这一反常变化是由于其内部结构缺陷的增加导致的。颗粒的内部缺陷随着熟化生长过程的进行而不断累积,从而导致大颗粒的CdSe纳米晶的结构无序度迅速增加。
2.Co掺杂ZnO纳米晶的结构和磁性研究
利用HR-TEM、XRD、XAFS和SQUID等方法研究了具有明显室温铁磁性的Zn_(1-x)Co_xO纳米晶的结构和磁性。尽管XRD和HR-TEM都没有探测到样品中含有杂相或包覆在ZnO晶格中的颗粒,但XAFS结果清晰的表明样品中同时存在金属Co相和掺杂进ZnO晶格中的Co离子相:在Zn_(0.98)Co_(0.02)O和Zn_(0.95)Co_(0.05)O中仅有64%和63%的Co掺杂进入ZnO晶格;而其他部分形成了平均尺寸小于10nm的金属Co纳米颗粒。样品的铁磁性并不是来源于掺杂相,而是来源于沉淀的金属Co纳米颗粒。样品的矫顽力随着Co含量的增加而降低,表明其铁磁性来源不同于纯金属相Co单畴颗粒,而可能是来源于Co纳米颗粒与表面包覆层的相互作用。
3.Se纳米管的形成机理研究
利用XAFS结合TEM等方法研究了可见光辐照辅助液相法制备的Se纳米管的形成机理。结果表明,Se纳米管的形成过程包含了三个典型阶段:(1)化学还原Se~(4+)为Se~0,并形成非晶Se微球;(2)部分非晶Se晶化为三方相Se(t-Se)纳米颗粒;(3)剩余的非晶Se继续晶化,但此阶段晶化沿着t-Se晶核的[001]晶向进行,形成管状结构。管状结构的形成是非晶Se链的扩散速度与反应速度相竞争的结果,该竞争导致了纳米管内部结构呈独特的楔形状。可见光辐照大大增加了Se原子链与晶核的反应速度,对Se纳米管的形成起着关键作用。
This thesis presents the investigation on nanomaterials by X-ray absorption fine structure (XAFS), combined with X-ray diffraction (XRD), transmission electron microscopy (TEM). It involves three different kinds of nanomaterials: (1)Ⅱ-Ⅵgroup CdSe semiconductor nanocrystals with controlled optoelectric property; (2) transition metal (cobalt) doped-ZnO nanocrystals with room temperature ferromagnetism; and (3) one-dimensional Se nanotubes with electrochemical hydrogen storage potential. This work provides structural aspect of nanomaterials, and will be helpful to controlled synthesis of nanomaterials as well as to better understanding of their properties.
1.Structural evolutions of CdSe nanocrystals in ripening process
The structural evolutions of CdSe nanocrystals (NCs) in the ripening process were investigated by high-resolution transmission electron microscopy (HR-TEM), XRD, and XAFS. A size-selective separation method was used to synthesize CdSe NCs with different grain sizes. The XAFS results indicate that the structural disorderσ_S~2 of the first nearest neighbor coordination Se-Cd shell in CdSe NCs rises from 0.0005 to 0.0012 and 0.0034 (?) as the size of NCs increases from 1.9 to 2.7 and 3.1 nm. The smallσ_S~2 of the 1.9 nm NCs unambiguously reveals that at this stage the CdSe NCs are well crystallized and almost free of interior defects. The unusual increase ofσ_S~2 with size can only be interpreted by the interior defects rather than surface defects of NCs. The interior defects produced in the core of the CdSe NCs through the ripening process are accumulated. This leads to a rapid increase in their structural disorders for the large CdSe NCs.
2. Structures and magnetism of Cobalt doped-ZnO nanocrystals
The structures and magnetism of Cobalt-doped ZnO nanocrystals (Zn_(1-x)Co_xO, x=0.02, 0.05) were investigated by HR-TEM, XRD, XAFS and SQUID. The Zn_(1-x)Co_xO nanocrystals demonstrate strong room-temperature ferromagnetism (FM) behavior from SQUID measurement. Although neither secondary phase nor imbedded cluster was detected by XRD and HR-TEM, XAFS has clearly shown the coexistence of metallic Co phase and Co~(2+) ionic phase incorporated in to ZnO matrix. EXAFS fittings indicate that only 64% and 63% of Co has effectively incorporated into wurtzite ZnO crystal lattice for the Zn_(1-x)Co_xO (x=0.02, 0.05) samples, while the rest precipitated out as Co clusters with average size well below 10 nm. The incorporated Co~(2+) ions in the highly crystalline ZnO nanocrystals did not contribute to FM signals, while the FM was assigned to the Co clustering in the samples. The precipitate of Co nanoparticle would result in RT-FM due to the interaction with the coatings/matrix, even its size is within the critical size for superparamagnetism.
3. Growth mechanism of Se nanotubes
Fluorescence XAFS and TEM were used to study the formation mechanism of trigonal selenium (t-Se) nanotubes synthesized by photothermally assisted solution method. The results demonstrate that the formation process of t-Se nanotubes contains three distinctive stages: (1) reduction of Se~(4+) to form amorphous Se (α-Se) phase, (2) partialα-Se crystallized into t-Se nanoparticles, (3) the crystallization of t-Se preferentially along [001] direction to form nanotubes. The formation of tubular structures is the outcome of competition between diffusion rate ofα-Se chains and reaction rate. This competition results in the cone-shaped hollow of inner tubular structures. Light irradiation plays an important role in the formation of tubular structures by accelerating the reaction rate of Se chains.
引文
[1] 王其武,刘文汉.1994.X射线吸收精细结构及其应用.[M].科学出版社.
[2] 马礼敦,杨福加.2001.同步辐射概论.[M].复旦大学出版社.
[3] 王浩.2006.功能材料信息.[J].ZnO基稀磁半导体纳米材料研究进展概况,3(5):19-23.
[4] 周勋,沈益斌,段满益,徐明,令狐荣锋.2007.材料导报.[J].ZnO基稀磁半导体材料研究进展,21(12):106-109.
[5] 韦世强,孙治湖,潘志云,闫文盛,钟文杰,贺博,谢治,韦正.2007.中国科学技术大学学报.[J].XAFS在凝聚态物质研究中的应用,37(4-5):426-440.
[6] Akai H. 1998. Phys. Rev. Lett. [J]. Ferromagnetism and Its Stability in the Diluted Magnetic Semiconductor (In, Mn)As, 81:3002-3005.
[7] Alivisatos A. P. 1996. Science [J]. Semiconductor clusters, nanocrystals, and quantum dots, 271:933-937.
[8] Artemyev M. V., Woggon U., Wannemacher R., Jaschinski H. and Langbein W. 2001. Nano Lett. [J]. Light trapped in a photonic dot: Microspheres act as a cavity for quantum dot emission, 1:309-314.
[9] Bethune D. S., Kiang C. H., de Vries M. S., Gorman G., Savoy R., Vazquez J. and Beyers R. 1993. Nature. [J]. Cobalt-catalysed growth of carbon nanotubes with single-atomic-layer walls, 363:605-607.
[10] Bruchez M. J., Moronne M., Gin P., Weiss S. and Alivisatos A. P. 1998. Science. [J]. Semiconductor nanocrystals as fluorescent biological labels, 281:2013-2016.
[11] Chan W. C. W. and Nie S. M. 1998. Science. [J]. Quantum dot bioconjugates for ultrasensitive nonisotopic detection, 281:2016-2018.
[12] Cheng B. and Samulski E. T. 2001. J. Mater. Chem. [J]. Fabrication and characterization of nanotubular semiconductor oxides In_2O_3 and Ga_2O_3,11:2901-2902.
[13] Cheng H. M., Li F., Su G., Pan H. Y., He L L., Sun X. and Dresselhaus M. S. 1998. Appl. Phys. Lett. [J]. Large-scale and low-cost synthesis of single-walled carbon nanotubes by the catalytic pyrolysis of hydrocarbons, 72:3282-3284.
[14] Cheng X. M. and Chien C. L. 2003. J. Appl. Phys. [J]. Magnetic properties of epitaxial Mn-doped ZnO thin films, 93:7876-7878.
[15] Chen M. and Gao L. 2006. Chem.Phys.Lett. [J]. Selenium nanotube synthesized via a facile template-free hydrothermal method, 417:132-136.
[16] Chen X. B., Samia A. C. S., Lou Y. B. and Burda C. 2005. J. Am. Chem. Soc. [J]. Investigation of the Crystallization Process in 2 nm CdSe Quantum Dots, 127:4372-4375.
[17] Chopra N. G, Luyken R., Cherrey J. K., Crespi V. H., Cohen M. L., Louie S. G. and Zettl A. 1995. Science. [J]. Boron Nitride Nanotubes, 269:966-967.
[18] Coey J. M. D, Venkatesan M. and Fitzgerald C. B. 2005. Nat. Mater. [J]. Donor impurity band exchange in dilute ferromagnetic oxides, 4:173-179.
[19] Dai H., Rinzler A. G, Nikolaev P., Thess A, Colbert D. T. and Smalley R. E. 1996. Chem. Phys. Lett. [J]. Single-wall nanotubes produced by metal-catalyzed disproportionation of carbon monoxide, 260:471475.
[20] Dai H., Wong E. W. and Lieber C. M. 1996. Science. [J]. Probing electrical transport in nanomaterials: conductivity of individual carbon nanotubes, 272:523-526.
[21] Deka S. and Joy P. A. 2005. Solid State Comm. [J]. Electronic structure and ferromagnetism of polycrystalline Zn1-xCoxO, 134:665-669.
[22] Dietl T., Ohno H., Matsukura E, Cibert J. and Ferrand D. 2000. Science. [J]. Zener Model Description of Ferromagnetism in Zinc-Blende Magnetic Semiconductors, 287: 1019-1022.
[23] Dloczik L., Engelhardt R., Ernst K., Fiechter S., Seiber I. and Konenkamp R. 2001. Appl. Phys. Lett. [J]. Hexagonal nanotubes of ZnS by chemical conversion of monocrystalline ZnO columns, 78:3687-3689.
[24] Donega C. M., Liljeroth P. and Vanmaekelbergh D. 2005. Small. [J]. Physicochemical Evaluation of the Hot-Injection Method, a Synthesis Route for Monodisperse Nanocrystals, 1:1152-1162.
[25] Endo M., Takeuchi K., Kobon K., Takahashi K., Kroto H. W. and Sarkar A. 1995. Carbon. [J]. Pyrolytic carbon nanotubes from vapor-grown carbon fibers, 33(7):873-881.
[26] Feldman Y., Wasserman E., Srolovitz D. J. and Tenne R. 1995. Science. [J]. High-Rate, Gas-Phase Growth of MoS2 Nested Inorganic Fullerenes and Nanotubes, 267:222-225.
[27] Filipponi A. and Cicco A. D. 1995. Phys. Rev. B [J]. X-ray-absorption spectroscopy and
??n-body distribution functions in condensed matter. I. Theory, 51:15122-15134.[28] Filipponi A. and Cicco A. D. 1995b. Phys. Rev. B [J]. X-ray-absorption spectroscopy and n-body distribution functions in condensed matter.Ⅱ. Data analysis and applications, 51: 15135-15149.
[29] Friche H. 1920. Phys.Rev. [J]. The k-characteristic absorption frequencies for the chemical elements magnesium to chromium, 16:202-215.
[30] Gates B., Yin Y. and Xia Y. 2000. J. Am. Chem. Soc. [J]. A Solution-Phase Approach to the Synthesis of Uniform Nanowires of Crystalline Selenium with Lateral Dimensions in the Range of 10-30 nm, 122:12582-12583.
[31] Gates B., Mayers B., Cattle B. and Xia Y. 2002. Adv. Funct. Mater. [J]. Synthesis and Characterization of Uniform Nanowires of Trigonal Selenium, 12:219-227.
[32] Hacohen Y. R., Grunbaum E., Tenne R., Sloan J. and Hutchison J. L. 1998. Nature. [J]. Cage Structures and Nanotubes of NiCl_2, 395:336-337.
[33] Hamad K. S., Roth R., Rockenberger J., van Buuren T. and Alivisatos A. P. 1999. Phys. Rev. Lett. [J]. Structural Disorder in Colloidal InAs and CdSe Nanocrystals Observed by X-Ray Absorption Near-Edge Spectroscopy, 83:3474-3477.
[34] Hertz G. 1920. z. Phys. [J]. Uber die Absorptionsfrequenzen der L-Serie, 3:19-25.
[35] Hutleen J. C., Jirage K. B. and Martin C. R. 1998. J. Am. Chem. Soc. [J]. Introducing Chemical Transport Selectivity into Gold Nanotubule Membranes, 120:6603-6604.
[36] Ohno H., Shen A., Matsukura F., Oiwa A., Endo A., Katsumoto S. and Iye Y. 1996. Appl. Phys. Lett. [J]. (Ga, Mn)As: A new diluted magnetic semiconductor based on GaAs, 69:363-365.
[37] Hoyer P. 1996. Langmuir. [J]. Formation of a titanium dioxide nanotube array, 12:1411-1413.
[38] Iijima S. 1991. Nature. [J]. Helical microtubules of graphitic carbon, 354:56-58.
[39] Iijima S and Ichihashi T. 1993. Nature. [J]. Single-shell carbon nanotubes of 1-nm diameter, 363:603-605.
[40] Jaklevic J., Kirby T. A. and Klein M. P. 1977. Solid State Commun. [J]. Fluorescence detection of EXAFS: Sensitivity enhancement for dilute species and thin films, 23:679-682.
[41] Jeong U. and Xia Y. 2005. Adv. Mater. [J]. Synthesis and Crystallization of Monodisperse Spherical Colloids of Amorphous Selenium, 17:102-106.
[42] Jin Z., Fukumura T., Kawasaki M., Ando K., Saito H. and Sekiguchi T. 2001. Appl. Phys. Lett. [J]. High throughput fabrication of transition-metal-doped epitaxial ZnO thin films: A series of oxide-diluted magnetic semiconductors and their properties, 78:3824-3826.
[43] Park J. H? Kim M. G, Jang H., Ryu M. S. and Kim Y. M. 2004. Appl. Phys. Lett. [J]. Co-metal clustering as the origin of ferromagnetism in Co-doped ZnO thin films, 84:1338-1341.
[44] Jung S. W., An S. J, Yi G C, Jung C. U., Lee S. I. and Cho S. 2002. Appl. Phys. Lett. [J]. Ferromagnetic properties of Zn1-xMnxO epitaxial thin films, 80:4561-4563.
[45] Kelly S., Ingalls R., Wang E, Ravel B. and Haskel D. 1998. Phys. Rev. B. [J]. X-ray-absorption fine-structure study of the Bl-to-B2 phase transition in RbCl, 57:7543-7550.
[46] Kim J. H., Kim H, Kim D., Ihm Y. E. and Choo W. K. 2002. J. Appl. Phys. [J]. Magnetic properties of epitaxially grown semiconducting Zn1-xCoxO thin films by pulsed laser deposition, 92:6066-6071.
[47] Kincaid B. and Eisenberger P. 1975. Phys.Rev.Lett. [J]. Synchrotron radiation studies of the K-Edge photoabsorption spectra of Kr, Br2, and GeCh: A comparison of theory and experiment, 34:1361-1364.
[48] Kittilstved K. R., Schwartz D. A., Tuan A. C, Heald S. M., Chambers S. A. and Gamelin D. R. 2006. Phys. Rev. Lett. [J]. Direct Kinetic Correlation of Carriers and Ferromagnetism in Co2+: ZnO, 97:037203-1-4.
[49] Kittilstved K. R., Norberg N. S. and Gamelin D. R. 2005. Phys. Rev. Lett. [J]. Chemical Manipulation of High-TC Ferromagnetism in ZnO Diluted Magnetic Semiconductors, 94:147209-1-4.
[50] Klimov V. I., Mikhailovsky A. A., Xu S., Malko A., Hollingsworth J. A., Leatherdale C. A., Eisler H. J. and Bawendi M. G 2000. Science. [J]. Optical Gain and Stimulated Emission in Nanocrystal Quantum Dots, 290:314-317.
[51] Koningsberger D. C. and Prins R. 1998. X-ray Absorption: Principles, Applications, Techniques of EXAFS, SESAFS, and XANES [M]. New York: John Wiley.
[52] Kronig R. de L. 1931. Z. Phys. [J], The theory of fine structure in the Xrayabsorption spectra, 70:317-323.
[53] Kronig R. de L. 1932. Z. Phys. [J]. Zur Theorie der Feinstruktur in den R6ntgenabsorptionsspektren II, 75:191-210.
[54] Lee H. J, Jeong S. Y, Cho C. R. and Park C. H. 2002. Appl. Phys. Lett. [J]. Study of diluted magnetic semiconductor: Co-doped ZnO, 81:4020-4022.
[55] Lee J., Sundar V. C. and Heine J. R. 2000. Adv. Mater. [J], Full color emission from II-VI semiconductor quantum dot-polymer composites, 12:1102-1105.
[56] Lieber C. M. 1998. Solid State Commun. [J], One-Dimensional Nanostructures: Chemistry, Physics & Applications, 107(11):607-616.
[57] Li J. Y., Chen X. L., Qiao Z. Y., Cao Y G. and Li H. 2001. J. Mater. Sci. Lett. [J]. Synthesis of GaN nanotubes, 20:1987-1988.
[58] Lim S. W., Hwang S. K. and Myoung J. M. 2003. Solid State Commun. [J]. Observation of optical properties related to room-temperature ferromagnetism in co-sputtered Zn1-xCoxO thin films, 125:231-235.
[59] Ma Y, Qi L., Ma J. and Cheng H. 2004. Adv.Mater. [J]. Micelle-Mediated Synthesis of Single-Crystalline Selenium Nanotubes, 16:1023-1026.
[60] Martinez B., Sandiumenge R, Balcells L1., Arbiol J., Sibieude F. and Monty C. 2005. Appl. Phys. Lett. [J]. Role of the microstructure on the magnetic properties of Co-doped ZnO nanoparticles, 86:103113-1-3.
[61] Matsushita T. and Phizackerley P. 1981. Jpn.J Appl.Phys. [J]. A fast X-ray absorption spectrometer for use with synchrotron radiation, 20:2223-2228.
[62] Mayers B. and Xia Y. 2002. Adv. Mater. [J]. Formation of Tellurium Nanotubes through Concentration Depletion at the Surfaces of Seeds, 14:279-282.
[63] Meron T. and Markovich G. 2005. J. Phys. Chem. B [J]. Ferromagnetism in Colloidal Mn2+-Doped ZnO Nanocrystals, 109:20232-20236.
[64] Murray, C. B., Norris D. J. and Bawendi M. G 1993. J. Am. Chem. Soc. [J]. Synthesis and characterization of nearly monodisperse CdE (E = S, Se, Te) semiconductor nanocrystallites, 115:8706-8715.
[65] Nakamura H. and Matsui Y 1995. J. Am. Chem. Soc. [J]. Silica Gel Nanotubes Obtained by the Sol-Gel Method, 117: 2651-2652.
[66] Nath M. and Rao C. N. R. 2001. J. Am. Chem. Soc. [J]. New metal disulfide nanotubes, 123:4841-4842.
[67] Nath M. and Rao C. N. R. 2002. Angew. Chem., Int. Ed. [J]. Nanotubes of Group 4 Metal Disulfides, 41:3451-3454
[68] Ohno H. 1998. Science. [J]. Making Nonmagnetic Semiconductors Ferromagnetic, 281:951-956.
[69] Peng X. G, Wickham J. and Alivisatos A. P. 1998. J. Am. Chem. Soc. [J], Kinetics of II-VI and III-V colloidal semiconductor nanocrystal growth: "Focusing" of size distributions, 120:5343-5344.
[70] Pu L., Bao X., Zou J. and Feng D. 2001. Angew. Chem. Int. Ed. [J]. Individual Alumina Nanotubes, 40:1490-1493.
[71] Prellier W., Fouchet A. and Mercey B. 2003. J. Phys.: Condens. Matter. [J]. Oxide-diluted magnetic semiconductors: a review of the experimental status, 15:R1583-R1601
[72] Qu L. H. and Peng X. G. 2002. J. Am. Chem. Soc. [J]. Control of photoluminescence properties of CdSe nanocrystals in growth, 124:2049 -2055.
[73] Qu L. H., Yu W. W. and Peng X.G. 2004. Nano Lett. [J]. In Situ Observation of the Nucleation and Growth of CdSe Nanocrystals, 4:465-469.
[74] Rao C. N. R., Govindaraj A. G, Deepak F. L., Gunari N. A. and Nath M. 2001. Appl. Phys. Lett. [J]. Surfactant-assisted synthesis of semiconductor nanotubes and nanowires, 78:1853-1855.
[75] Ravel B., Cockayne E., Newville M. and Rabe K. M. 1999. Phys. Rev. B [J]. Combined EXAFS and first-principles theory study of Pb1-xGexTe, 60:14632-14642.
[76] Rehr J. J. and Albers R. C. 2000. Rev. Mod. Phys. [J]. Theoretical approaches to X-ray absorption fine structure, 72:621-654.
[77] Rode K., Anane A., Mattana R., Contour J. P., Durand O. and LeBourgeois R. 2003. J. Appl. Phys. [J]. Magnetic semiconductors based on cobalt substituted ZnO, 93:7676-7679.
[78] Rode K., Mattana R., Anane A., Cros V., Jacquet E., Contour J. P., Petroff F, Fert A., Arrio M. A., Sainctavit P., Bencok P., Wilhelm F., Brookes N. B. and Rogalev A. 2008. Appl. Phys. Lett. [J]. Magnetism of (Zn, Co)0 thin films probed by x-ray absorption Spectroscopies, 92:012509-1-3.
[79] Rogach A. L., Kornowski A., Gao M. Y., Eychmulller A. and Weller H. 1999. J. Phys. Chem. B [J]. Synthesis and Characterization of a Size Series of Extremely Small Thiol-Stabilized CdSe Nanocrystals, 103:3065-3069.
[80] Saeki H., Tabata H. and Kawai T. 2001. Solid State Commun. [J].Magnetic and electric properties of vanadium doped ZnO films, 120:439-443.
[81] Sarma S. D, Hwang E. H. and Kaminski A. 2003. Phys. Rev. B [J]. Temperature-dependent magnetization in diluted magnetic semiconductors, 67:155201-1-16.
[82] Sato K. and Katayams H. 2000. Jpn J. Appl. Phys. [J]. Material Design for Transparent Ferromagnets with ZnO-Based Magnetic Semiconductors, 39: L555-L558.
[83] Sayers D. E., Stern E. A, Lytle F. W. 1971. Phys. Rev. Lett. [J], New technique for investigating noncrystalline structures: Fourier analysis of the extended X-ray-absorption fine structure, 27:1204-1207.
[84] Schlamp M. C, Peng X. G. and Alivisatos A. P. 1997. J. Appl. Phys. [J]. Improved efficiencies in light emitting diodes made with CdSe (CdS) core/shell type nanocrystals and a semiconducting polymer, 82:5837 -5842.
[85] Schwartz D. A., Norberg N. S., Nguyen Q. P., Parker J. M. and Gamelin D. R. 2003. J. Am. Chem. Soc. [J]. Magnetic Quantum Dots: Synthesis, Spectroscopy, and Magnetism of Co2+- andNi2+-DopedZnO Nanocrystals, 125,13205-13218.
[86] Shibata T., Bunker B. A., Zhang Z., Meisel D., Vardeman II C. F. and Gezelter J. D. 2002. J. Am. Chem. Soc. [J]. Size-Dependent Spontaneous Alloying of Au-Ag Nanoparticles, 124(40):11989-11996.
[87] Spahr M. E., Bitterli P., Nesper R., Muller M., Krumeich F. and Nissen H. U. 1998. Angew. Chem. Int. Ed. [J]. Redox-Active Nanotubes of Vanadium Oxide, 37:1263-1265.
[88] Stem E. A., Newville M, Ravel B., Haskel D. and Yacoby Y. 1995. Physica B [J]. The UWXAFS analysis package: philosophy and details, 208&209:117-120.
[89] Stern E. 1974. Phys. Rev. B [J]. Theory of the extended X-ray-absorption fine structure, 10:3027-3037.
[90] Stohr J. and Jaeger R. 1982. Phys. Rev. B [J]. Absorption-edge resonances,corehole Screening, and orientation of chemisorbed molecules:CO,NO,and Nz on Ni(100), 26:4111-4131.
[91] Story T., Galazka R. R., Frankel R. B. and Wolff P. A. 1986. Phys. Rev. Lett. [J]. Carrier-concentration-induced ferromagnetism in PbSnMnTe, 56:777-779.
[92] Tans S. J., Devore M. H., Dai H., Thess A., Smalley R. E., Geerligs L. J., Dekker C. 1997. Nature. [J]. Individual single-wall carbon nanotubes as quantum wires, 386:474-477.
[93] Tenne R., Margulis L., Genut M. and Hodes G. 1992. Nature. [J]. Polyhedral and cylindrical structures of tungsten disulphide, 360:444-446.
[94] Tenne R. 2003. Angew. Chem. Int. Ed. [J]. Advances in the Synthesis of Inorganic Nanotubes and Fullerene-Like Nanoparticles, 42:5124-5132.
[95] Thess A., Lee R., Nikolaev P., Dai H., Petit P., Robert J., Xu C, Lee Y. H., Kim S. G, Rinzler A. G, Colbert D. T., Scuseria G. E., Tomanek D., Fischer J. E. and Smalley R. E. 1996. Science. [J]. Crystalline ropes of metallic carbon nanotubes, 273:483-487.
[96] Tourillon G, Pontonnier L., Levy J. P. and Langlais V. 2000. Electrochem. Solid-State Lett. [J], Electrochemically Synthesized Co and Fe Nanowires and Nanotubes, 3:20-23.
[97] Ueda K., Tabata H. and Kawai T. 2001. Appl. Phys. Lett. [J]. Magnetic and electric properties of transition-metal-doped ZnO films, 79:988-990.
[98] Wakano T., Fujimura N, Morinaga Y., Abe N., Ashida A. and Ito T. 2001. Physica E. [J]. Magnetic and magneto-transport properties of ZnO: Ni films, 10:260-264.
[99] Wang X. F, Xu J. B., Zhang B., Yu H. G, Wang J., Zhang X. X., Yu J. G. and Li Q. 2006. Adv. Mater. [J]. Signature of Intrinsic High-Temperature Ferromagnetism in Cobalt-Doped Zinc Oxide Nanocrystals, 18:2476-2480.
[100] Wolf S. A., Awschalom D. D., Buhrman R. A., Daughton J. M., von Molnar S., Roukes M. L., Chtchelkanova A. Y and Treger D. M. 2001. Science. [J]. Spintronics: A Spin-Based Electronics Vision for the Future, 294:1488-1495.
[101] Xi G, Xiong K., Zhao Q., Zhang R., Zhang H. and Qian Y. 2006. Crystal Growth & Design. [J]. Nucleation-Dissolution-Recrystallization: A New Growth Mechanism for t-Selenium Nanotubes, 6:577-582.
[102] Xiong Y, Xie Y, Yang J., Zhang R., Wu C. and Du G 2002. J. Mater. Chem. [J]. In situ micelle-template-interface reaction route to CdS nanotubes and nanowires, 12:3712-3716.
[103] Xiong Y, Mayers B. T. and Xia Y. 2005. Chem. Commun. [J]. Some Recent Developments in the Chemical Synthesis of Inorganic Nanotubes, 37(1):5013-5022.
[104] Zener C. 1951a. Phys. Rev. [J]. Interaction between the d Shells in the Transition Metals, 81:440-444.
[105] Zener C. 1951b. Phys. Rev. [J]. Interaction between the d-Shells in the Transition Metals. II. Ferromagnetic Compounds of Manganese with Perovskite Structure, 82: 403-405.
[106] Zhang B., Dai W., Ye X., Hou W. and Xie Y. 2005. J. Phys. Chem. B [J]. Solution-Phase Synthesis and Electrochemical Hydrogen Storage of Ultra-Long Single-Crystal Selenium Submicrotubes, 109:22830-22835.
[107] Zhang B., Dai W., Ye X., Zuo F. and Xie Y 2006. Angew. Chem. Int. Ed. [J]. Photothermally Assisted Solution-Phase Synthesis of Microscale Tubes, Rods, Shuttles, and an Urchin-Like Assembly of Single-Crystalline Trigonal Selenium, 45:2571-2574.
[108] Zhang H., Gilbert B., Huang F. and Banfield J. F. 2003. Nature. [J]. Water-driven structure transformation in nanoparticles at room temperature, 424:1025-1029.
[109] Zhang H., Yang D., Ji, Y. Ma X., Xu J. and Que D. 2004. J. Phys. Chem. B [J]. Selenium Nanotubes Synthesized by a Novel Solution Phase Approach, 108:1179-1182.
[110] Zhang P. and Sham T. K. 2003. Phys. Rev. Lett. [J]. X-Ray Studies of the Structure and Electronic Behavior of Alkanethiolate-Capped Gold Nanoparticles: The Interplay of Size and Surface Effects, 90:245502-1-4.
[111] Zhang S. Y, Liu Y, Ma X. and Chen H. Y 2006. J. Phys. Chem. B [J]. Rapid, Large-Scale Synthesis and Electrochemical Behavior of Faceted Single-Crystalline Selenium Nanotubes, 110:9041-9047.
[1] 王其武,刘文汉.1994.X射线吸收精细结构及其应用.[M].科学出版社.
[2] 马礼敦,杨福加.2001.同步辐射概论.[M].复旦大学出版社.
[3] 钟文杰,贺博,李征,韦世强.2001.中国科学技术大学学报.[J].USTCXAFS 2.0软件包,31:328-333.
[4] 韦世强,孙治湖,潘志云,闫文盛,钟文杰,贺博,谢治,韦正.2007.中国科学技术大学学报.[J].XAFS在凝聚态物质研究中的应用,37(4-5):426-440.
[5] James R. W. 1963. Solid State Phys. [M]. The dynamical theory of x-ray diffraction, 15:53-220.
[6] Koningsberger D. C. and Prins R. 1998. X-ray Absorption: Principles, Applications, Techniques of EXAFS, SESAFS, and XANES [M]. New York: JohnWiley.
[7] Newville M., Livins P., Yacoby Y., Rehr J. J. and Stern E. A. 1993. Phys. Rev. B [J]. Near-edge x-ray-absorption fine structure of Pb: A comparison of theory and experiment, 47:14126-14131.
[8] Newville M. 1995. Local thermodynamic measurements of dilute binary alloys using XAFS, [D]: [PhD thesis], Washington: University of Washington.
[9] Pinsker Z. G. 1978. Dynamical Scattering of X-ray in Crystals. [M]. Berlin: Springer-Verlag.
[10] Rehr J. J., Stern E. A., Martin R. L. and Davidson E. R. 1978. Phys. Rev. B [J]. Extended x-ray-absorption fine-structure amplitudes-Wave-function relaxation and chemical effects, 17:560-565.
[11] Rehr J. J. and Albers R. C. 1990. Phys. Rev. B [J]. Scattering-matrix formulation of curved-wave multiple-scattering theory: Application to x-ray-absorption fine structure, 41:8139-8149.
[12] Stern E. A. and Heald S.M. 1979. Rev. Sci. Instr. [J]. Data reduction and analysis were performed according to recommended procedures, 50:1579-1583.
[13] Stern E. A., Bunker B. A. and Heald S. M. 1980. Phys. Rev. B [J]. Many-body effects on extended x-ray absorption fine structure amplitudes, 21:5521-5539.
[14] Stern E. A. and Kim K. 1981. Phys. Rev. B. [J]. Thickness effect on the extended-x-ray-absorption-fine-structure amplitude, 23:3781-3787.
[15] Stern E. A. and Heald S. M. 1983. Basic Principles and Applications of EXAFS, in Handbook of Synchrotron Radiation. [M]. ed. Koch E. E., New York: North-Holland, 995.
[16] Stern E. A. 1993. Phys. Rev. B [J]. Number of relevant independent points in x-ray-absorption fine-structure spectra, 48:9825-9827.
[17] Stern E. A, Newville M., Ravel B. and Yacoby Y. 1995. Physica B [J]. UWXAFS analysis package: philosophy and details, 208&209:117-120.
[18] Zabinsky S. I., Rehr J. J., Ankudinov A., Albers R. C. and Eller M. J. 1995. Phys. Rev. B [J]. Multiple-scattering calculations of x-ray-absorption spectra, 52:2995-3009.
[1] 钟文杰,贺博,李征,韦世强.2001.中国科学技术大学学报.[J].USTCXAFS 2.0软件包,31:328-333.
[2] Ankudinov A. L., Ravel B., Rehr J. J. and Conradson S. D. 1998. Phys. Rev. B [J]. Real-space multiple-scattering calculation and interpretation of x-ray-absorption near-edge structure, 58:7565-7576.
[3] Carter A. C., Bouldin C. E., Kemner K. M., Bell M. I., Woicik J. C. and Majetich S. A. 1997. Phys. Rev. B [J]. Surface structure of cadmium selenide nanocrystallites, 55:13822-13828.
[4] Chen X. B., Samia A. C. S., Lou Y. B. and Burda C. 2005. J. Am. Chem. Soc. [J]. Investigation of the Crystallization Process in 2 nm CdSe Quantum Dots, 127:4372-4375.
[5] Donega C. M., Liljeroth P. and Vanmaekelbergh D.2005. Small. [J]. Physicochemical Evaluation of the Hot-Injection Method, a Synthesis Route for Monodisperse Nanocrystals, 1:1152-1162.
[6] Eychm(u|¨)ller A. and Rogach A. L. 2000. Pure Appl. Chem. [J]. Chemistry and photophysics of thiol-stabilized Ⅱ-Ⅵ semiconductor nanocrystals, 72:179-188.
[7] Gaponik N., Talapin D. V., Rogach A. L., Hoppe K., Shevchenko E. V., Kornowski A., Eychmulller A. and Weller H. 2002. J. Phys. Chem. B [J]. Thiol-Capping of CdTe Nanocrystals: An Alternative to Organometallic Synthetic Routes, 106:7177-7185.
[8] Huang F., Zhang H. Z. and Banfield F. 2003. Nano Lett. [J]. Two-step crystal growth kinetics observed in hydrothermal coarsening of nanocrystalline ZnS, 3:373-378.
[9] Hamad K. S., Roth R., Rockenberger J., van Buuren T. and Alivisatos A. P. 1999. Phys. Rev. Lett. [J]. Structural Disorder in Colloidal InAs and CdSe Nanocrystals Observed by X-Ray Absorption Near-Edge Spectroscopy, 83:3474-3477.
[10] Jose R., Zhanpeisov N. U., Fukumura H., Baba Y. and Ishikawa M. 2006. J. Am. Chem. Soc. [J]. Structure-Property Correlation of CdSe Clusters Using Experimental Results and First-Principles DFT Calculations, 128: 629-636.
[11] Leung K. and Whaley K. B. 1999. J. Chem. Phys. [J]. Surface relaxation in CdSe nanocrystals, 110:11012-1022.
[12] Liu B. and Zeng H. C. 2003. J. Am. Chem. Soc. [J]. Hydrothermal synthesis of ZnO nanorods in the diameter regime of 50 nm, 125:4430-4431.
[13] Marcus M. A., Flood W., Steigerwald ML, Brus L. and Bawendi M. 1991. J. Phys. Chem. [J]. Structure of Capped CdSe Clusters by EXAFS, 95:1572-1576.
[14] McGinley C, Riedler M., Moller T., Borchert H., Haubold S, Haase M. and Weller H. 2002. Phys. Rev. B [J]. Evidence for surface reconstruction on InAs nanocrystals, 65:245308-1-5.
[15] Perm R. L. and Banfield J. F. 1998. Science [J]. Imperfect Oriented Attachment: Dislocation Generation in Defect-Free Nanocrystals, 281:969-971.
[16] Peng Z. A. and Peng X. 2002. J. Am. Chem. Soc. [J]. Nearly Monodisperse and Shape-Controlled CdSe Nanocrystals via Alternative Routes: Nucleation and Growth, 124:3343-3353.
[17] Ribeiro C, Lee E. J. H., Longo E. and Leite E. R. 2005. ChemPhysChem. [J]. A Kinetic Model to Describe Nanocrystal Growth by the Oriented Attachment Mechanism, 6:690-696.
[18] Rockenberger J., Troger L., Rogach A. L., Tischer M., Grundmann M., Eychmuller A. and Weller H. 1998. J. Chem. Phys. [J]. The contribution of particle core and surface to strain, disorder and vibrations in thiolcapped CdTe nanocrystals, 108:7807-7812.
[19] Rochenberger J., Troger L., Kornowski A, Vossmeyer T, Eychmulller A., Feldhaus J., and Weller H. 1997. J. Phys. Chem. B [J]. EXAFS Studies on the Size Dependence of Structural and Dynamic Properties of CdS Nanoparticles, 101:2691-2701.
[20] Rogach A. L., Kornowski A., Gao M. Y., Eychmulller A. and Weller H. 1999. J. Phys. Chem. B [J]. Synthesis and Characterization of a Size Series of Extremely Small Thiol-Stabilized CdSe Nanocrystals, 103:3065-3069.
[21] Tiemann M., Weiβ O., Hartikainen J., Marlow F. and Linden M. 2005. ChemPhysChem [J]. Early Stages of ZnS Nanoparticle Growth Studied by In-situ Stopped-flow UV Absorption Spectroscopy, 6:2113-2119.
[22] Tiemann M., Marlow E, Brieler F. and Linden M. 2006. J. Phys. Chem. B [J]. Early Stages of ZnS Growth Studied by Stopped-flow UV Absorption Spectroscopy: Effects of Educt Concentrations on the Nanoparticle Formation, 110:23142-23147.
[23] Xu H. L., Wang W. Z. and Zhu W. 2006. Chem. Lett. [J]. Oriented Attachment of Crystalline CuS Nanorods, 35: 264-265.
[24] Zhang Z. P., Sun H. P., Shao X. Q., Li D. F, Yu H. D. and Han M. Y. 2005. Adv. Mater. [J]. Three-Dimensionally Oriented Aggregation of a Few Hundred Nanoparticles into Monocrystalline Architectures, 17:42-47.
[1] 钟文杰,贺博,李征,韦世强.2001.中国科学技术大学学报.[J].USTCXAFS 2.0软件包,31:328-333.
[2] Ney A., Ollefs K., Ye S., Kammermeier T., Ney V., Kaspar T. C., Chambers S. A., Wilhelm F. and Rogalev A. 2008. Phys. Rev. Lett. [J]. Absence of Intrinsic Ferromagnetic Interactions of Isolated and Paired Co Dopant Atoms in Zn_(1-x)Co_xO with High Structural Perfection, 100:157201-14.
[3] Ankudinov A. L., Ravel B., Rehr J. J. and Conradson S. D. 1998. Phys. Rev. B [J]. Real-space multiple-scattering calculation and interpretation of x-ray-absorption near-edge structure, 58, 7565-7576.
[4] Chang G. S., Kurmaev E. Z., Boukhvalov D. W., Finkelstein L. D., Colis S., Pedersen T. M., Moewes A. and Dinia A. 2007. Phys. Rev. B [J]. Effect of Co and O defects on the magnetism in Co-doped ZnO: Experiment and theory, 75:195215-1-7.
[5] Choi S. H., Kim E. G., Park J., An K., Lee N., Kim S. C. and Hyeon T. 2005. J. Phys. Chem. B [J]. Large-Scale Synthesis of Hexagonal Pyramid-Shaped ZnO Nanocrystals from Thermolysis of Zn-Oleate Complex, 109:14792-14794.
[6] Dalpian G. M. and Chelikowsky J. R. 2006. Phys. Rev. Lett. [J]. Self-Purification in Semiconductor Nanocrystals, 96:226802-1-4.
[7] Gubin S. P., Spichkina Y. I., Yu. K. A. G., Yurkova. Y., Kozinkinc A. V., Nedoseikinac T. I.., Korobova M. S. and Tishin A. M. 2003. J. Magn. Magn. Mater. [J]. Magnetic and structural properties of Co nanoparticles in a polymeric matrix, 265:234-242.
[8] Hormes J., Modrow H., B(o|¨)nnemann H. and Kumar C. S. S. R. 2005. J. Appl. Phys. [J]. The influence of various coatings on the electronic, magnetic, and geometric properties of cobalt nanoparticles, 97:10R102-1-6.
[9] Hsu H. S., Huang J. C. A., Huang Y. H., Liao Y. F., Lin M. Z., Lee C. H., Lee J. F., Chen S. F., Lai L. Y. and Liu C. P. 2006. Appl. Phys. Lett. [J]. Evidence of oxygen vacancy enhanced room-temperature ferromagnetism in Co-doped ZnO, 88:242507-1-3.
[10] Kittilstved K. R., Schwartz D. A., Tuan A. C., Heald S. M., Chambers S. A. and Gamelin D. R. 2006. Phys. Rev. Lett. [J]. Direct Kinetic Correlation of Carriers and Ferromagnetism in Co2+: ZnO, 97:037203-14.
[11] Lee H. J., Jeong S. Y., Cho C. R. and Park C. H. 2002. Appl. Phys. Lett. [J], Study of diluted magnetic semiconductor: Co-doped ZnO, 81:4020-4022.
[12] Lee H. J., Ryu G H., Kim S. K., Kim S. A., Lee C. H., Jeong S. Y. and Cho C. R. 2004. Phys. Stat. Sol. (b) [J]. A study of magnetic clusters in Co-doped ZnO using neutron scattering, 241:2858-2861.
[13] Leslie-Pelecky D. L. and Rieke R. D. 1996. Chem. Mater. [J]. Magnetic Properties of Nanostructured Materials, 8:1770-1783.
[14] Li X. L., Wang Z. L., Qin X. F.., Wu H. S., Xu X. H. and Gehring G. A. 2008. J. Appl. Phys. [J]. Enhancement of magnetic moment of Co-doped ZnO films by postannealing in vacuum, 103:023911-1-5.
[15] Liu X. C, Shi E. W, Chen Z. Z., Chen B. Y, Zhang T, Song L. X., Zhou K. J., Cui M. Q., Yan W. S., Xie Z., He B. and Wei S. Q. 2008. J. Phys.: Condens. Matter [J]. Effect of oxygen partial pressure on the local structure and magnetic properties of Co-doped ZnO films, 20:025208-1-5.
[16] Meron T. and Markovich G. 2005. J. Phys. Chem. B [J]. Ferromagnetism in Colloidal Mn2+-Doped ZnO Nanocrystals, 109:20232-20236.
[17] Naeem M., Hasanain S. K, Kobayashi M., Ishida Y, Fujimori A., Buzby S. and Shah S. I. 2006. Nanotechnology [J]. Effect of reducing atmosphere on the magnetism of Zn1-xCoxO (0≤ x≤0.10) nanoparticles, 17:2675-2680.
[18] Oyanagi H., Sakamoto K. and Sakamoto T. 1992. Jpn. J. Appl. Phys. [J]. Heterointerfaces in Strained-Layer Superlattices Studied by Surface-Sensitive XAFS, S32-1: 119-124.
[19] Oyanagi H., Sakamoto T., Sakamoto K., Matsushita T., Yao T. and Ishiguro T. 1988. J. Phys. Soc. Japan [J]. Si/Ge/Si Monolayer Heterostructure on Si(100) Studied by Surface-Sensitive EXAFS, 57:2086-2092.
[20] Park J. H., Kim M. G, Jang H. M., Ryu S. and Kim Y M. 2004. Appl. Phys. Lett. [J]. Co-metal clustering as the origin of ferromagnetism in Co-doped ZnO thin films, 84:1338-1340.
[21] Pan Z. Y, Sun Z. H., Xie Z., Xu J. H., Kojima I. and Wei S. Q. 2006. J. Phys. D: Appl. Phys. [J]. Interfacial intermixing of TiN/Si3N4 super-hard multilayer films studied by fluorescence x-ray absorption fine structure, 39:2796-2802.
[22] Shi T. E, Zhu S. Y., Sun Z. H., Wei S.Q. and Liu W. H. 2007. Appl. Phys. Lett. [J]. Structures and magnetic properties of wurtzite Zn1-xCoxO dilute magnetic semiconductor nanocomposites, 90:102108-1-3.
[23] Ueda K., Tabata H. and Kawai T. 2001. Appl. Phys. Lett. [J]. Magnetic and electric properties of transition-metal-doped ZnO films, 79:988-990.
[24] Viswanatha R., Sapra S., Gupta S. S., Satpati B., Satyam P. V., Dev B. N. and Sarma D. D. 2004. J. Phys. Chem. B [J]. Synthesis and characterization of Mn-doped ZnO nanocrystals, 108:6303-6310.
[25] Yin S., Xu M. X., Yang L., Liu J. F., Rosner H, Hahn H., Gleiter H., Schild D, Doyle S., Liu T., Hu T. D., Takayama-Muromachi E. and Jiang J. Z. 2006. Phys. Rev. B [J]. Absence of ferromagnetism in bulk polycrystalline Zn0.9Co0.1O,73:224408-1-5.
[26] Yuhas B. D., Fakra S., Marcus M. A. and Yang P. D. 2007. Nano Lett. [J]. Probing the Local Coordination Environment for Transition Metal Dopants in Zinc Oxide Nanowires, 7:905-909.
[27] Zanghi D., Teodorescu C. M., Petroff F, Fischer H., Bellouard C, Clerc C, Pelissier C. and Traversea A. 2001. J. Appl. Phys. [J]. Reduced magnetic moment per atom in small Ni and Co clusters embedded in A1N, 90:6367-6373.
[1] 钟文杰,贺博,李征,韦世强.2001.中国科学技术大学学报.[J].USTCXAFS 2.0软件包,31:328-333.
[2] Ankudinov A. L., Ravel B., Rehr J. J. and Conradson S. D. 1998. Phys. Rev. B [J]. Real-space multiple-scattering calculation and interpretation of x-ray-absorption near-edge structure, 58:7565-7576.
[3] Kolobov A. V., Oyanagi H., Tanaka K. and Tanaka K. 1997. Phys. Rev. B [J]. Structural study of amorphous selenium by in situ EXAFS: Observation of photoinduced bond alternation, 55:726-734.
[4] Ma Y., Qi L., Ma J. and Cheng H. 2004. Adv.Mater. [J]. Micelle-Mediated Synthesis of Single-Crystalline Selenium Nanotubes, 16:1023-1026.
[5] Mayers B. and Xia Y. 2002. Adv. Mater. [J]. Formation of Tellurium Nanotubes through Concentration Depletion at the Surfaces of Seeds, 14:279-282.
[6] Pan Z. Y., Sun Z. H., Xie Z., Xu J. H., Kojima I. and Wei S. Q. 2006. J. Phys. D: Appl. Phys. [J]. Interfacial intermixing of TiN/Si_3N_4 super-hard multilayer films studied by fluorescence x-ray absorption fine structure, 39:2796-2802.
[7] Takahashi H., Fujikawa T. and Konishi T. 2006. e-J. Surf. Sci. Nanotech. [J]. XAFS study of nanocrystalline selenium embedded in amorphous matrix, 4:213-218.
[8] Xi G., Xiong K., Zhao Q., Zhang R., Zhang H. and Qian Y. 2006. Crystal Growth & Design. [J]. Nucleation-Dissolution-Recrystallization: A New Growth Mechanism for t-Selenium Nanotubes, 6:577-582.
[9] Xiong Y., Mayers B. T. and Xia Y. 2005. Chem. Commun. [J]. Some Recent Developments in the Chemical Synthesis of Inorganic Nanotubes, 37(1): 5013-5022.
[10] Zhang B., Dai W., Ye X., Zuo F. and Xie Y. 2006. Angew. Chem. Int. Ed. [J]. Photothermally Assisted Solution-Phase Synthesis of Microscale Tubes, Rods, Shuttles, and an Urchin-Like Assembly of Single-Crystalline Trigonal Selenium, 45:2571-2574.