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Stannyl-substituted [(RZn)4(OR′)4] cubanes with different tin-containing alkoxy groups [Ph3SnOZnMe] ( 1), [Ph3SnOZnEt] ( 2), [Me3SnOZn tBu] ( 3), and [Ph3SnOZn tBu] ( 4) are easily accessible by Brønsted acid-base reaction of the corresponding triorganotin hydroxides with ZnMe2, ZnEt2, and Zn( tBu)2, respectively. All new compounds 1- 4 were characterized by various spectroscopic methods and the structures of 1 and 3 were confirmed by single-crystal X-ray diffraction analysis. The thermal degradation of the precursors 1-4 under dry synthetic air (20 % O2, 80 %N2) was studied and the final oxide materials were characterized by employing powder X-ray diffraction (PXRD) analysis, inductively coupled plasma-optical emission spectrometry (ICP-OES), transmission and scanning electron microscopy (SEM and TEM), energy dispersive X-ray spectroscopy (EDX), and atomic force microscopy (AFM). Remarkably, compounds 1 and 2 proved to be suitable as single-source precursors (SSPs) for the efficient preparation of tin-doped ZnO nanoparticles with tunable tin concentrations as a promising system for steering and improving the optoelectronic properties of tin-doped ZnO. Using 3 as SSP furnishes tin-containing ZnO materials with good electron mobilities at relatively low processing temperatures (350 °C) for thin-film transistor (TFT) applications. All the thin films of tin-doped ZnO prepared by spin-coating on silicon wafers are of great homogeneity and amorphous structure, which is promising for future applications in the field of transparent conducting oxides (TCOs). [ABSTRACT FROM AUTHOR]

The syntheses, structural characterization, and thermal degradation of a series of the new indium and gallium siloxide dimers [{Me2In(OSiEt3)}2] ( 1), [{Me2Ga(OSiEt3)}2] ( 2), [{Me2In(OSi(O tBu)3)}2] ( 3), [{Me2Ga(OSi(O tBu)3)}2] ( 4), and In[OSi(O tBu)3)] ( 5) is reported. Compounds 1- 4 are readily accessible by facile Brönsted reaction of InMe3 or GaMe3 with the corresponding silanols Et3SiOH and ( tBuO)3SiOH, respectively. Compound 5 could be obtained by analogous protolysis of [In{N(SiMe3)2}3] with an excess amount of ( tBuO)3SiOH. The suitability of 1- 5 to serve as molecular precursors for low-temperature synthesis of amorphous indium and gallium oxide for electronic applications was probed. Thus their thermal degradation was studied by Thermogravimetric/differential thermogravimetry analysis (TGA/DTG). Compounds 1- 4 were decomposed under dry synthetic air (20 % O2, 80 % N2) at low temperature to yield amorphous indium oxide and gallium oxide particles, respectively. In contrast, thermal degradation of 5 affords amorphous indium silicate. 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 spectroscopy (EDX). Thin-film field-effect transistors (FETs) could be fabricated through spin-coating of silicon-wafers with solutions of 1 in toluene and subsequent calcination under dry synthetic air at 350 °C. These films exhibit very good FET performance with a field-effect mobility of 3.0×10−1 cm2 V−1 s and an on/off current ratio of 108. [ABSTRACT FROM AUTHOR]

The syntheses and structural elucidation of dimeric [Sn(OCyHex)2] ( 1), its corresponding (cyclohexoxy)alkalistannates(II) [{M(OCyHex)3Sn}2] (M=Li ( 2), Na ( 3), K ( 4)), and of the first heteroleptic heterotermetallic Li/In/Sn-haloalkoxide clusters [X2In{LiSn2(OCyHex)6}] (X=Br ( 5), Cl ( 6)) with a double seco-norcubane core are reported. They represent suitable precursors for new amorphous indium tin oxide (ITO) materials as transparent conducting oxides with drastically reduced concentrations of expensive indium, while maintaining their high electrical performance. In fact, compounds 5 and 6 were successfully degraded under dry synthetic air at relatively low temperature, resulting in new semiconducting tin-rich ITOs homogeneously dispersed in a tin oxide/lithium oxide matrix. The obtained particles were investigated and characterised by different analytical techniques, such as powder XRD, IR spectroscopy, SEM, TEM and energy-dispersive X-ray spectroscopy (EDX). The analytical data confirm that the final materials consist of tin-containing indium oxide embedded in an amorphous tin oxide matrix. The typical broadening and shift of the observed indium oxide reflections to higher 2 θ values in the powder XRD pattern clearly indicated that tin centres were successfully incorporated into the In2O3 lattice and partially occupied In3+ sites. Investigations by EDX mapping proved that Sn was homogeneously distributed in the final materials. Thin-film field-effect transistors (FETs) were fabricated by spin-coating of silicon wafers with solutions of 5 in toluene and subsequent calcination under dry air (25-700 °C). The FETs prepared with precursor 5 exhibited excellent performances, as shown by a charge-carrier mobility of 6.36×10−1 cm2 V−1 s (calcination at 250 °C) and an on/off current ratio of 106. [ABSTRACT FROM AUTHOR]