Organozinc Precursor-Derived Crystalline ZnO Nanoparticles: Synthesis, Characterization and Their Spectroscopic Properties

Nanomaterials

Feng Fu¹  Yucang Liang²  Susanne Wicker²  Egil Severin Erichsen³  Xiao Wang⁴ 

[1] College of Chemistry & Chemical Engineering, Yan’an University, Shaanxi Key Laboratory of Chemical Reaction Engineering, Yan’an 716000, China;Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany;Laboratory for Electron Microscopy, University of Bergen, Allégaten 41, 5007 Bergen, Norway;School of Physics and Electronics, Hunan University, Changsha 410082, China;

关键词: organozinc precursor;    thermal decomposition;    zinc oxide;    nanoparticle;    size effect;    spectroscopic properties;   

DOI  :  10.3390/nano8010022

来源: DOAJ

【 摘 要 】

Crystalline ZnO-ROH and ZnO-OR (R = Me, Et, iPr, nBu) nanoparticles (NPs) have been successfully synthesized by the thermal decomposition of in-situ-formed organozinc complexes Zn(OR)2 deriving from the reaction of Zn[N(SiMe3)2]2 with ROH and of the freshly prepared Zn(OR)2 under an identical condition, respectively. With increasing carbon chain length of alkyl alcohol, the thermal decomposition temperature and dispersibility of in-situ-formed intermediate zinc alkoxides in oleylamine markedly influenced the particle sizes of ZnO-ROH and its shape (sphere, plate-like aggregations), while a strong diffraction peak-broadening effect is observed with decreasing particle size. For ZnO-OR NPs, different particle sizes and various morphologies (hollow sphere or cuboid-like rod, solid sphere) are also observed. As a comparison, the calcination of the fresh-prepared Zn(OR)2 generated ZnO-R NPs possessing the particle sizes of 5.4~34.1 nm. All crystalline ZnO nanoparticles are characterized using X-ray diffraction analysis, electron microscopy and solid-state 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The size effect caused by confinement of electrons’ movement and the defect centres caused by unpaired electrons on oxygen vacancies or ionized impurity heteroatoms in the crystal lattices are monitored by UV-visible spectroscopy, electron paramagnetic resonance (EPR) and photoluminescent (PL) spectroscopy, respectively. Based on the types of defects determined by EPR signals and correspondingly defect-induced probably appeared PL peak position compared to actual obtained PL spectra, we find that it is difficult to establish a direct relationship between defect types and PL peak position, revealing the complication of the formation of defect types and photoluminescence properties.

【 授权许可】

Unknown