▎ 摘　　要

NOVELTY - Preparing expanded graphene by ultra-low temperature comprises soaking wet graphene oxide in aqueous solution of non volatile acid, carrying out acidification treatment, separating acidified graphene oxide and acid solution, directly carrying out ultra-low temperature heat treatment of the wet and acidified graphene oxide at 50-110 degrees C to obtain primary product, washing with water and purifying. USE - The method is useful for preparing expanded graphene by ultra-low temperature (claimed). ADVANTAGE - The method: is simple; is easy to operate; improves production efficiency; and is economical. The expanded graphene is suitable for large scale production.