Disclosed are a high-entropy nitride ceramic fiber, and a preparation method and use thereof. The high-entropy ceramic fiber comprises Ti, Hf, Ta, Nb, and Mo; the high-entropy nitride ceramic fiber presents single crystal phase, and each of the elements are uniformly distributed at molecular level. The preparation method of the high-entropy ceramic fiber comprises: mixing a high-entropy ceramic precursor comprising the target metal elements, a spinning aid, and a solvent uniformly to prepare a precursor spinning solution, followed by working procedures of spinning, pyrolyzation, and nitriding to prepare the high-entropy nitride ceramic fiber. The high-entropy nitride ceramic fiber can be used in photocatalysis process of carbon dioxide to prepare methane.

Disclosed are a high-entropy nitride ceramic fiber, and a preparation method and use thereof. The high-entropy ceramic fiber comprises Ti, Hf, Ta, Nb, and Mo; the high-entropy nitride ceramic fiber presents single crystal phase, and each of the elements are uniformly distributed at molecular level. The preparation method of the high-entropy ceramic fiber comprises: mixing a high-entropy ceramic precursor comprising the target metal elements, a spinning aid, and a solvent uniformly to prepare a precursor spinning solution, followed by working procedures of spinning, pyrolyzation, and nitriding to prepare the high-entropy nitride ceramic fiber. The high-entropy nitride ceramic fiber can be used in photocatalysis process of carbon dioxide to prepare methane.

The present invention provides a thin-film forming raw material including a scandium compound represented by the following general formula (1), a method of producing a thin-film including using the thin-film forming raw material, and a novel scandium compound:

##STR00001##

where R.sup.1 represents an alkyl group having 1 to 4 carbon atoms, R.sup.2 represents an alkyl group having 2 or 3 carbon atoms, and R.sup.3 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

The present invention provides a thin-film forming raw material including a scandium compound represented by the following general formula (1), a method of producing a thin-film including using the thin-film forming raw material, and a novel scandium compound:

##STR00001##

where R.sup.1 represents an alkyl group having 1 to 4 carbon atoms, R.sup.2 represents an alkyl group having 2 or 3 carbon atoms, and R.sup.3 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

A method for converting an N,N-dialkylamide compound into an ester compound includes using a fourth period transition metal complex as a catalyst. The fourth period transition metal complex is obtained by a reaction of a precursor having a fourth period transition metal with a nitrogen-containing compound or a phosphorus-containing compound.

Methods are provided for synthesizing W(IV) beta-diketonate precursors. Additionally, methods are provided for forming W containing thin films, such as WS.sub.2, WN.sub.x, WO.sub.3, and W via vapor deposition processes, such as atomic layer deposition (ALD) type processes and chemical vapor deposition (CVD) type processes. Methods are also provided for forming 2D materials containing W.

Methods are provided for synthesizing W(IV) beta-diketonate precursors. Additionally, methods are provided for forming W containing thin films, such as WS.sub.2, WN.sub.x, WO.sub.3, and W via vapor deposition processes, such as atomic layer deposition (ALD) type processes and chemical vapor deposition (CVD) type processes. Methods are also provided for forming 2D materials containing W.

Methods are provided for synthesizing W(IV) beta-diketonate precursors. Additionally, methods are provided for forming W containing thin films, such as WS.sub.2, WN.sub.x, WO.sub.3, and W via vapor deposition processes, such as atomic layer deposition (ALD) type processes and chemical vapor deposition (CVD) type processes. Methods are also provided for forming 2D materials containing W.

A process for the preparation of the hydrated and/or anhydrous acetylacetonate of a chemical element Me, where the chemical element Me is chosen from alkaline earth metals, transition metals and lanthanides, comprises a stage of reaction in an aqueous medium of the Me oxide or hydroxide introduced in the solid form and of acetylacetone, the acetylacetone being in excess with respect to the Me oxide or hydroxide.

A process for the preparation of the hydrated and/or anhydrous acetylacetonate of a chemical element Me, where the chemical element Me is chosen from alkaline earth metals, transition metals and lanthanides, comprises a stage of reaction in an aqueous medium of the Me oxide or hydroxide introduced in the solid form and of acetylacetone, the acetylacetone being in excess with respect to the Me oxide or hydroxide.