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A single-step synthetic method was developed to obtain ultrafine MgO nanocrystals by ultimately simple solvothermal treatment of a precursor solution containing magnesium acetylacetonate in acetonitrile at 400 °C for 10 min. HRTEM images and calculations based on Scherer equation showed that the average size of obtained ultrafine MgO nanocrystals was ca. 7 nm.

CeO_2-ZrO_2 composite nanoparticles with mesoporous and spherical morphologies were assembled into different homogeneously dispersed, domain, and core-shell structures by changing the reaction conditions, such as the heating rate, acid, and solvent, in supercritical alcohols. Ce_xZr_O_2 with homogeneous structures were prepared from Ce(NO_3)_3 and ZrO(NO_3)_2 in the presence of formic acid in methanol by rapid heating (500℃/min) to 300℃, while CeO_2–ZrO_2 with domain structures were obtained by slow heating (5.4℃/min). Treatment of mesoporous and spherical ZrO_2 nanoparticles with a Ce(NO_3)_3 solution in supercritical conditions yielded CeO_2-ZrO_2 nanocomposites with core-shell morphologies, while solvents playing a key role in controlling the thickness of the outer shell; methanol produced a very thin outer shell (

A MoS2 layered thin film was grown by atmospheric-pressure solution-based mist CVD on a 30 mm2 large-area substrate at 400 °C, which is a significantly lower growth temperature than that of conventional CVD. The film formation was reliably confirmed by Raman spectroscopy, grazing incidence X-ray diffraction (GIXD), and transmission electron microscope (TEM). Possibly, film formation energy was decreased by dissolving (NH3)6Mo7O24 4H2O in methanol owing to formation of an intermediate product, whose decomposition temperature was lower than 760 °C — the decomposition temperature observed in thermogravimetric-differential thermal analysis (TG-DTA). Optical constants were derived by spectroscopic ellipsometry measurements, whose results indicate the reasonably good quality of MoS2 and the suitability of mist CVD in response to the large-area low-temperature growth request from industry.

Yttrium iron garnet (YIG) thin films were deposited on c-plane sapphire substrates under atmospheric pressure by a mist CVD technique, and their chemical composition and optical properties were examined. The thin films deposited at 450 °C showed an [Y]/[Fe] ratio of 0.57, indicating the deposition of yttrium iron oxide, while the molar ratio of [Y]/[Fe] in the precursor solution was set at 1.5. A thermodynamic model was developed to explain the reaction paths of the YIG thin film fabrication process using thermogravimetric differential thermal analysis (TG-DTA) results. The model indicates that the decomposition rate of yttrium acetylacetonate [Y(acac)3 nH2O] was much lower than that of iron acetylacetonate [Fe(acac)3], providing a plausible explanation for the large difference between the composition ratio of the thin films and that of the precursor solutions.