▎ 摘　　要

NOVELTY - Reduced graphene oxide (RGO)/cotton sponge composite material comprises cotton sponge and reduced graphene oxide loaded on the cotton sponge, where the cotton sponge comprises multiple layers of hierarchical structure stacked in sequence, and vertically extending channel that is formed between adjacent hierarchical structures with the central channel in the cotton sponge as the starting point, and the width of the channel gradually increases toward both ends. USE - The composite material is useful for industrial and commercial applications. ADVANTAGE - The composite material has a three-dimensional skeleton structure by forming a structure with a wide gap at both ends and a narrow gap in the middle, high light-to-heat conversion efficiency and low heat loss, and uses cotton sponge having excellent mechanical stability in both the dry state and the wet state because the cotton fabric carrier has an effective connection structure i.e. a cotton fiber connection between the layer and the layer and an ordered pore structure in which the pore structure is vertically arranged. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a preparation method of RGO/cotton sponge composite material, involving preparing graphene oxide, soaking cotton sponge in the graphene oxide aqueous solution, drying at 50-80 degrees C after soaking to obtain a cotton sponge loaded with reduced graphene oxide, stretching the RGO/cotton sponge wetted with ethanol at a transverse elongation of 30-70%, and fixing with a clamp to obtain the product.