Ultrafine gold nanocomposite, and preparation method and use thereof

A method for preparing an ultrafine gold nanocomposite, comprising the following steps:

• mixing a cyclodextrin metal-organic framework (CD-MOF) material, chloroauric acid and a solvent to obtain a mixture;
• and
• subjecting the mixture to incubation to obtain the ultrafine gold nanocomposite;
• wherein
• the method further comprises, before the mixing, preparing the CD-MOF material by:
• mixing γ-cyclodextrin (γ-CD), an alkali metal compound, water and an organic solvent to obtain a mixed material;
• and subjecting the mixed material to coordination to obtain a coordination product liquid;
• and
• mixing the coordination product liquid and a surfactant to obtain an admixture;
• and subjecting the admixture to crystallization to obtain the CD-MOF material;
• and
• an amount of the CD-MOF material is based on an amount of the γ-CD;
• a molar ratio of the γ-CD to the chloroauric acid is in a range of 5:1 to 7.5:1;
• and a ratio of an amount of substance of the chloroauric acid to a volume of the solvent is in a range of 1.25 mmol:
• 1 L to 1.5 mmol:
• 1 L.