Application of lactam as solvent in nanomaterial preparation

A sol-gel method for synthesis of nanomaterials with lactam as the solvent comprising the steps:

• adding 0.01-100 weight parts of hydrolyzable precursor and 100 weight parts of lactam solvent into a reactor to form a mixture;
• stirring the mixture at 80-150° C. for 0.1-2 hr to make the lactam solvent molten and to fully dissolve and disperse the hydrolysable precursor in the molten lactam solvent, and adding 0.01-50 weight parts of water for hydrolysis with the hydrolysis temperature of 80˜250° C. and hydrolysis time of 0.01-48 hr to obtain sol;
• performing gelatinization on the sol in the reactor at 80˜270° C. for 0.01-96 hr to obtain a gelatinized mixture;
• washing the gelatinized mixture with absolute alcohol to obtain a washed mixture;
• and
• drying the washed mixture to obtain synthesized nanomaterials;
• wherein the hydrolyzable precursor is selected from the group consisting of inorganic metal salts of halogen, nitrate, sulfate or acetate anions and metal organics,
• wherein the lactam contained in the lactam solvent is one or more substances selected from the group consisting of cyclic amides and cyclic amide derivatives,
• wherein the general structural formula of the cyclic amide is:
• the general structural formula of the cyclic amide derivatives is:
• wherein R is a substance selected from hydrogen, halogen, alkyl, hydroxy, alkoxy or acyl;
• and
• wherein the nanomaterials are substances containing inorganic particles having a particle size of greater than 1 nm and less than or equal to 100 nm;
• the content of the inorganic particles is no less than 0.01% of the substance;
• the inorganic particles are mixtures composed of one or more substances selected from the group consisting of hydroxides, oxides, sulfides, metals and inorganic salts.

A high temperature pyrolysis method for synthesis of nanomaterials with lactam as the solvent comprising the steps:

• adding 0.01-100 weight parts of pyrolyzable precursor and 100 weight parts of lactam solvent into a reactor to form a mixture;
• stirring the mixture at 80-150° C. for 0.1-2 hr to create a molten lactam solvent from the lactam solvent and to fully dissolve or disperse the pyrolyzable precursor in the molten lactam solvent;
• performing pyrolysis on the molten lactam solvent by raising the temperature to 100˜270° C. for 0.1-20 hr whereby a pyrolysis product is formed;
• washing the pyrolysis product with absolute alcohol;
• and
• drying the washed pyrolysis product to obtain synthesized nanomaterials,
• wherein the pyrolyzable precursor is selected from soluble inorganic salts pyrolyzable in solvent at a temperature of no higher than 280° C. or from metal organics pyrolyzable in solvent at a temperature of no higher than 280° C.,
• wherein the lactam contained in the lactam solvent is one or more of the substances selected from cyclic amides or cyclic amide derivatives,
• wherein the general structural formula of the cyclic amide is:
• wherein the general structural formula of the cyclic amide derivatives is:
• wherein R is a substance selected from hydrogen, halogen, alkyl, hydroxy, alkoxy or acyl, and
• wherein the nanomaterials are substances containing inorganic particles having a particle size of greater than 1 nm and less than or equal to 100 nm;
• the content of the inorganic particles is no less than 0.01% of the substance;
• the inorganic particles are mixtures composed of one or more substances selected from hydroxides, oxides, sulfides, metals or inorganic salts.