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[摘要]：The first heterobimetallic alkyl(trirnethylstannoxy)-zinc clusters with the formula [Me(3)SnOZnR](4) (R = Me 1, Et 2) are facile accessible by the Bronsted acid base reaction of trimethyltin hydroxide with the respective zinc dialkyls ZnR(2) (R = Me, Et). The resulting products 1 and 2 can be isolated as white solids in high yields (> 95%) and were characterized by multinuclear NMR, elemental analysis, FTIR spectroscopy, mass spectrometry, and single-crystal X-ray diffraction analyses. They proved to serve as unprecedented low-temperature single source precursors (SSPs) for the fabrication of tin-containing ZnO as well as zinc stannate semiconducting materials and could be successfully utilized in field effect transistor (FET) applications. The thermal degradation of and 2 under dry synthetic air, monitored by thermogravimetric analysis (TGA and TGA-IR), indicates high volatility of the trimethylstannyl group, which turned out to be the key parameter to control the tin concentration in the final semiconducting product. Low temperatures of degradation as well as low heating rates reduce the rate of tin loss and lead to mainly amorphous, nanosized tin-containing zinc oxide materials. Moreover, degradation at higher temperatures (> 350 degrees C) and higher heating rates produces a homogeneous mixture of zinc stannate Zn(2)Sna(4) and ZnO as major products. Remarkably, calcination of the latter mixtures at 600 degrees C favors crystallization and increases the surface area up to 298 m(2) g(-1). This unexpected increase in surface area is accompanied by a decrease in the tin concentration owing to the liberation of SnO(2). All of these products were analyzed by multiple techniques including powder X-ray diffraction analysis (PXRD), transmission electron microscopy (TEM), and energy dispersive X-ray (EDX) spectroscopy. Finally, semiconducting thin films of tin-doped ZnO with 1.5 wt % tin were produced, without the use of any additive, through spin-coating of a mixture of precursor 1 and homometallic [MeZnO(t)Bu](4) and subsequent degradation at 350 degrees C in dry air. These films can serve as suitable semiconducting layers in FET applications and show a high performance, that is, high electron mobility and homogeneity after annealing at 350 degrees C in air. |
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