Zinc Oxide Nanoparticles with Defects

Zinc oxide in the form of nanoscale materials can be regarded as one of the most important semiconductor oxides at present. However, the question of how chemical defects influence the properties of nanoscale zinc oxide materials has seldom been addressed. In this paper, we report on the introduction of defects into nanoscale ZnO, their comprehensive analysis using a combination of techniques (powder X-ray diffraction (PXRD), X-ray absorption spectroscopy/extended X-ray absorption fine structure (XAS/EXAFS), electron paramagnetic resonance (EPR), magic-angle spinning nuclear magnetic resonance (MAS-NMR), Fourier-transform infrared (FTIR), UV-vis, and photoluminescence (PL) spectroscopies coupled with ab-initio calculations), and the investigation of correlations between the different types of defects. It is seen that defect-rich zinc oxide can be obtained under kinetically controlled conditions of ZnO formation. This is realized by the thermolysis of molecular, organometallic precursors in which ZnO is pre-organized on a molecular scale. It is seen that these precursors form ZnO at low temperatures far from thermodynamic equilibrium. The resulting nanocrystalline ZnO is rich in defects. Depending on conditions, ZnO of high microstructural strain, high content of oxygen vacancies, and particular content of heteroatom impurities can be obtained. It is shown how the mentioned defects influence the electronic properties of the semiconductor nanoparticles.

[1]  A. Stoneham.  Theory of defects in solids , 1979 .

[2]  Bixia Lin,et al.  Green luminescent center in undoped zinc oxide films deposited on silicon substrates , 2001 .

[3]  Bruce E. Gnade,et al.  Mechanisms behind green photoluminescence in ZnO phosphor powders , 1996 .

[4]  Chun-Hway Hsueh,et al.  Using Microstructure to Attack the Brittle Nature of Silicon Nitride Ceramics , 1995 .

[5]  Reinhold F. Fink,et al.  A multi-configuration reference CEPA method based on pair natural orbitals , 1993 .

[6]  J. Lavalley,et al.  Infrared study of the interaction between CO and H2 on ZnO: Mechanism and sites of formation of formyl species , 1982 .

[7]  F. Kruis,et al.  Chemical vapor synthesis of size-selected zinc oxide nanoparticles. , 2005, Small.

[8]  Larry E. Halliburton,et al.  Role of copper in the green luminescence from ZnO crystals , 2002 .

[9]  W. Sibley,et al.  Radiation Damage in ZnO Single Crystals , 1968 .

[10]  K. Fink.  Ab initio cluster calculations for the absorption energies of F and F+ centers in bulk ZnO. , 2005, Physical chemistry chemical physics : PCCP.

[11]  Seiji Isotani,et al.  Energetics of native defects in ZnO , 2001 .

[12]  D. C. Reynolds,et al.  Characterization of homoepitaxial p-type ZnO grown by molecular beam epitaxy , 2002 .

[13]  F. Gan,et al.  Electron spin resonance properties of ZnO microcrystallites , 1998 .

[14]  A. Chadwick,et al.  The interdependence of defects, electronic structure and surface chemistry. , 2004, Dalton transactions.

[15]  Alexey A. Sokol,et al.  From CO2 to methanol by hybrid QM/MM embedding , 2001 .

[16]  Paul Roth,et al.  Formation and properties of ZnO nano-particles from gas phase synthesis processes , 2002 .

[17]  A. Hervé,et al.  Optically detected magnetic resonance and optically detected ENDOR of shallow indium donors in ZnO , 1982 .

[18]  M. Anpo,et al.  ESR and photoluminescence evidence for the photocatalytic formation of hydroxyl radicals on small TiO2 particles , 1985 .

[19]  A. Alivisatos,et al.  Nanocrystals: Building blocks for modern materials design , 1997 .

[20]  J. Spence.  Oxygen in Crystals--Seeing Is Believing , 2003, Science.

[21]  Bruno K. Meyer,et al.  Oxygen vacancies in ZnO , 2003 .

[22]  M. Thurnauer,et al.  Trapped holes on titania colloids studied by electron paramagnetic resonance , 1993 .

[23]  岩崎 裕,et al.  Landolt-Bornstein New Series Group III, Vol.3, T. Mitsui, et al,: Ferro- and Antiferro-electric Substances, Springer-Verlag, Berlin, 1969, 584ページ, 27.5×19.5cm, 37,000円 , 1973 .

[24]  M. Schulz.  ESR experiments on Ga donors in ZnO crystals , 1975 .

[25]  T. Miyata,et al.  Transparent conducting ZnO thin films prepared on low temperature substrates by chemical vapour deposition using Zn(C5H7O2)2 , 1994 .

[26]  T. Srećković,et al.  Electronic paramagnetic resonance investigation of the evolution of defects in zinc oxide during tribophysical activation , 1997 .

[27]  M. Casanove,et al.  Synthesis and characterization of monodisperse zinc and zinc oxide nanoparticles from the organometallic precursor [Zn(C6H11)2] , 2002 .

[28]  D. Look,et al.  Magnetic resonance studies of ZnO , 2001 .

[29]  H. W. D. R. nat.,et al.  Rationales Katalysatordesign am Beispiel des Methanolkatalysators , 2004 .

[30]  B. Meyer.  First-principles study of the polar O-terminated ZnO surface in thermodynamic equilibrium with oxygen and hydrogen , 2004 .

[31]  Brant A. Peppley,et al.  Methanol–steam reforming on Cu/ZnO/Al2O3. Part 1: the reaction network , 1999 .

[32]  A. Alivisatos.  Semiconductor Clusters, Nanocrystals, and Quantum Dots , 1996, Science.

[33]  F. Kruis,et al.  From molecules to metastable solids: solid-state and chemical vapour syntheses (CVS) of nanocrystalline ZnO and Zn , 2003 .

[34]  H. B. Milner.  Endeavour , 1965, Nature.

[35]  J. Maier.  Complex oxides: high temperature defect chemistry vs. low temperature defect chemistry , 2003 .

[36]  P. Knauth.  Defect and transport properties of nanocrystalline ceramics and thin films , 2002 .

[37]  J. Schneider,et al.  Notizen: Paramagnetische Resonanz von Donatoren in Zinkoxyd , 1961 .

[38]  P. Sherwood,et al.  Identification and Characterization of Active Sites and Their Catalytic Processes—the Cu/ZnO Methanol Catalyst , 2003 .

[39]  A. Hervé,et al.  Magnetic resonance studies of shallow donors in zinc oxide , 1982 .

[40]  S. Pearton,et al.  Recent advances in processing of ZnO , 2004 .

[41]  D. Louër,et al.  X-ray diffraction study of the early stages of the growth of nanoscale zinc oxide crystallites obtained from thermal decomposition of four precursors. General concepts on precursor-dependent microstructural properties , 1998 .

[42]  H. C. Ong,et al.  Photoluminescence and cathodoluminescence studies of stoichiometric and oxygen-deficient ZnO films , 2001 .

[43]  Volker Staemmler,et al.  An efficient first-order CASSCF method based on the renormalized Fock-operator technique , 1989 .

[44]  E. C. Ashby,et al.  New, convenient, and stereospecific method for the dehydration of alcohols. Thermal decomposition of magnesium, zinc, and aluminum alkoxides , 1979 .

[45]  Eric A. Meulenkamp,et al.  Synthesis and Growth of ZnO Nanoparticles , 1998 .

[46]  A. Dadgar,et al.  Direct evidence for selective impurity incorporation at the crystal domain boundaries in epitaxial ZnO layers , 2004 .

[47]  G. Ceder,et al.  First-principles study of native point defects in ZnO , 2000 .

[48]  C. Wolden,et al.  An interrogation of the zinc oxide–gallium oxide phase space by plasma enhanced chemical vapor deposition , 2004 .

[49]  J. Smith,et al.  ESR of electron irradiated ZnO confirmation of the F + center , 1970 .

[50]  L. Jing,et al.  The preparation and characterization of ZnO ultrafine particles , 2002 .