▎ 摘　　要

NOVELTY - Preparing a graphene coated sponge comprises: filling mineral wool with a solution comprising graphene material by successive squeezing to obtain a mineral wool soaked with graphene material; transferring the mineral wool soaked with graphene material into a hydrothermal reactor and submitting it to heating at 60-240 degrees C for 5 minutes to 72 hours to have graphene material bonded to mineral wool; and cleaning the heated material to remove the unbonded graphene material and reaction byproducts from the graphene coated mineral wool. USE - The method is useful for preparing a graphene coated sponge which is useful as a water-treating agent (claimed). ADVANTAGE - The method provides graphene coated sponge which: exhibits enhanced electrocatalytic activity; is flexible; and is easily shaped when wet. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) graphene coated sponge obtained by the method; (2) electrode obtained by connecting to electrical current the graphene coated sponge; (3) electrochemical flow-through reactor comprising the graphene coated sponge electrodes including at least an anode and a cathode; and (4) treating water comprising passing the water through the electrochemical flowthrough reactor.