▎ 摘　　要

NOVELTY - A catalyst comprises 10-50 wt.% graphene oxide and 40-90 wt.% hydrotalcite. The graphene oxide contains a large number of electronegative groups such as hydroxyl group, carboxylic acid group and carbonyl group. The cation of the hydrotalcite is composed of a divalent metal ion and a trivalent metal ion in a molar ratio of 2-5. USE - The catalyst is useful for cycloaddition reaction of epoxide including ethylene oxide or propylene oxide (all claimed). DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the catalyst, which involves: (1) dissolving precursors of divalent metal ion and trivalent metal ion in deionized water to prepare a solution (A) with a total concentration of 0.5-2 mol/l; (2) dissolving sodium hydroxide and sodium carbonate or potassium hydroxide and potassium carbonate in deionized water to prepare an alkaline solution (B) with a concentration of 1.5-2.5 mol/l, where the concentration of sodium carbonate or potassium carbonate is 0.2-0.5 mol/l, and the concentration of sodium hydroxide or potassium hydroxide is 1-2 mol/l; (3) adding graphene oxide to deionized water to obtain a mixture (C), where the mass of graphene oxide and deionized water is 1:200-10:100; (4) heat preserving at 40-60 degrees C under stirring conditions, carrying out co-current co-precipitation on the solutions (A) and (B) in the mixture (C) to obtain a slurry (D), where the pH of the precipitation reaction is 9-11, and the volume ratio of solution (A) and solution (C) is 1-4, and dynamically aging the slurry (D) under hydrothermal conditions at 60-90 degrees C for 6-15 hours to obtain a slurry (F); and (5) subjecting the slurry (F) to filtering, washing and drying at 100-120 degrees C for 10-20 hours.