▎ 摘　　要

NOVELTY - Hydrothermal synthesis of alpha -manganese dioxide-graphene nanosheet includes adding ultrafine graphite to concentrated sulfuric acid solution, cooling, mixing, adding potassium permanganate, mixing, adding deionized water, mixing, adding hydrogen peroxide solution, mixing, filtering, washing, drying, adding graphite oxide, performing ultrasonic treatment, reacting, cooling, adding potassium permanganate and sodium carboxymethyl cellulose, mixing, adding three-dimensional reduced graphene hydrogel and manganese dioxide dispersion, reacting, centrifuging, washing, cleaning and drying. USE - Method of hydrothermal synthesis of alpha-manganese dioxide-graphene nanosheet (claimed). ADVANTAGE - The method prevents aggregation of graphene, improves discharge efficiency of electrode material and is simple and easy to control. DETAILED DESCRIPTION - Hydrothermal synthesis of alpha -manganese dioxide-graphene nanosheet comprises adding 1 g ultrafine graphite to 25 mL concentrated sulfuric acid solution, cooling at 0-5 degrees C, mixing for 30 minutes, adding 4 g potassium permanganate, placing at 35-38 degrees C water bath, mixing for 120 minutes, adding 60 mL deionized water, mixing at 80-90 degrees C for 15 minutes, adding 5% hydrogen peroxide solution, mixing, filtering, adding 5% dilute hydrochloric acid solution, washing filter cake with deionized water to neutralize, drying at 60-70 degrees C for 20-25 hours, adding 0.16 g graphite oxide in 400 mL sodium hydroxide solution, dispersing for 1-2 hours, centrifuging at 8000-10000 revolutions per minute (rpm) for 2-10 minutes, performing ultrasonic treatment for 3 hours, placing graphene oxide sol in hydrothermal reactor lined with PTFE, reacting at 200-220 degrees C for 12-15 hours, cooling naturally at room temperature, removing sample, adding 0.1 g potassium permanganate and 1 mL sodium carboxymethyl cellulose in 20 mL deionized water, mixing for 5 minutes, adding three-dimensional reduced graphene hydrogel and manganese dioxide dispersion to autoclave, reacting at 200-220 degrees C for 48-50 hours, centrifuging at 4000-5000 rpm for 10-20 minutes, washing with deionized water and absolute ethanol, cleaning and drying at 70-80 degrees C for 12-15 hours.