▎ 摘　　要

NOVELTY - Nano-calcium carbonate/graphene hydrogel composition is claimed. The composition is prepared by e.g. adding manganese chloride aqueous solution to graphene oxide aqueous solution, stirring, processing ultrasonic oscillation to obtain uniform manganese chloride/graphene oxide suspension, adding potassium permanganate aqueous solution into manganese chloride/graphene oxide suspension to obtain reaction solution, placing reaction solution in sealed reaction kettle for isothermal reaction, and reacting 4 equivalents of manganate ion with 5 equivalents of carbon and 4 equivalents of hydrogen ion. USE - The hydrogel composition is useful for catalytic materials and electrode materials. ADVANTAGE - The hydrogel composition has good electrochemical performance. The method is simple and reliable; and is suitable for industrial production. DETAILED DESCRIPTION - Nano-calcium carbonate/graphene hydrogel composition is claimed. The hydrogel composition is prepared by (i) adding manganese chloride aqueous solution to graphene oxide aqueous solution, stirring and processing ultrasonic oscillation to obtain a uniform manganese chloride/graphene oxide suspension; (ii) adding potassium permanganate aqueous solution into manganese chloride/graphene oxide suspension to obtain a reaction solution; (iii) placing the reaction solution in a sealed reaction kettle for isothermal reaction, reacting 4 equivalents of manganate ion with 5 equivalents of carbon and 4 equivalents of hydrogen ion to obtain 4 equivalents of manganese carbonate, carbon dioxide and two equivalents of water, reacting carbon dioxide and water to obtain two equivalents of hydrogen ion and carbonate ion, and reacting carbonate ion and manganese ion to obtain manganese carbonate, and obtaining nano-calcium carbonate/graphene hydrogel complex crude product; and (iv) adding deionized water to the nano-calcium carbonate/graphene hydrogel complex crude product, and washing to obtain nano-calcium carbonate/graphene hydrogel composite product. An INDEPENDENT CLAIM is also included for preparing the nano-calcium carbonate/graphene hydrogel composition by above mentioned method.