Sol-gel processing methods are frequently used for the fabrication of lead zirconate titanate (PZT) thin films for many electronic applications. Our standard approach for film fabrication utilizes lead acetate and acetic acid modified metal alkoxides of zirconium and titanium in the preparation of our precursor solutions. This report highlights some of our recent results on the effects of the addition of a second chelating ligand, acetylacetone, to this process. We discuss the changes in film drying behavior, densification and ceramic microstructure which accompany acetylacetone additions to the precursor solution and relate the observed variations in processing behavior to differences in chemical precursor structure induced by the acetylacetone ligand. Improvements in thin film microstructure, ferroelectric and optical properties are observed when acetylacetone is added to the precursor solution.

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Colloidal synthesis of ZnO nanocrystals (NCs) from zinc alkoxy alkyl precursors in the 1-methyl imidazole/H 2 O coordinating solvent is reported. The results of NC structural and optical characterization are presented. 2007 Optical Society of America OCIS codes:; (160.2540) Fluorescent and luminescent materials; (250.5230) PhotoluminescenceSemiconductor colloidal nanocrystals (NCs) have recently been the subject of extensive research due to their novel optoelectronic properties that can greatly benefit such applications as solar cells [1] and light emitting diodes [2]. ZnO NCs possess a number of properties making them very attractive for optical applications, such as wide bandgap, large exciton binding energy, radiation hardness, and strong surface-defect-related green emission. As such, they are of interest as potential high-speed nanophosphors for conversion of UV light into visible emission.Due to their high solubility, low decomposition and crystallization temperatures, and ease of modification, metal alkoxides (M(OR) x ) are excellent precursors to metal oxide nanoparticles. These precursors are of interest since they cleanly decompose to the oxide, and readily crystallize at low temperatures. A variety of zinc precursors (i.e., "Zn(OR)(Et)(solv)" and "Zn(OR) 2 (solv) 2 ") were synthesized in [3] through the reaction of diethyl zinc (ZnEt 2 with Et = CH 2 CH 3 ) and an appropriate alcohol (HOR). Different solvents (solv) used for the precursor synthesis were pyridine (py), tetrahydrofuran (THF), or 1-methyl imidazole (MeIm), while the ligand OR represents one of the following: neo-pentoxide (ONep), tetrahydrofurfurylalkoxide (OTHF), 2,6-dimethyl phenoxide (DMP), 2,6-diisopropyl phenoxide (DIP), and 2,6-di-tert-butyl phenoxide (DBP). The ZnO nanocrystals were synthesized in [3] by injecting the appropriate zinc precursor, dissolved in py, into hot MeIm and H 2 O (14.5:0.5) under reflux conditions. The alkyl part of the zinc precursor allowed for rapid decomposition, while the oxide either resulted from hydrolysis, decomposition of the alkoxide, or the presence of water. The nanocrystals formed were either rods 7 -13 nm in diameter, 50 -95 nm long, or irregular spheres less than 10 nm in diameter, depending on the zinc alkoxide precursor used.In this paper, we report on colloidal synthesis of ZnO NCs performed according to one of the schemes proposed in [3]. First, the zinc alkoxide precursors [Zn(µ-ONep)(Et)(py)] 2 (abbreviated as ZnONep) and Zn(DIP)(Et)(py) 2 (abbreviated as ZnDIP) were synthesized under inert atmosphere conditions through the reaction of ZnEt 2 with HONep or H-DIP, respectively (Eq 1):ZnEt 2 + nHOR → ZnEt 2-n (OR) n , n = 1, 2(1) HOR = H-ONep or H-DIPFor ZnONep, a 1:1 molar ratio of H-ONep (0.133 g) was slowly added to a mixture of ZnEt 2 (1.50 ml) in pyridine with constant stirring. After stirring for 12 h, the reaction was set aside to allow the volatile component to slowly evaporate, yielding X-ray quality crystals. For ZnDIP, H-DIP (0.615 g) and ZnEt 2 (4.00 ml) in py were manipulated...