▎ 摘　　要

In this paper, a green one-step strategy is developed to fabricate three-dimensional (3D) graphene-based multifunctional material with the aid of tannic acid. Tannic acid (TA), a typical plant polyphenol widely present in woods, reduced GO and induced the self-assembly of reduced graphene oxide into graphene hydrogel. The preparation process was carried out in aqueous media under atmosphere pressure without using any toxic reducing agent or special instrument, which is a facile, green, and low-cost method. The as-prepared monolithic 3D graphene exhibits high porosity, low density, hydrophobicity, good mechanical performance, and thermal stability. In addition, it shows excellent adsorption toward dyes, oils, and organic solvent, which should be a promising candidate for efficient adsorbents in water purification. Moreover, the tannic acid retained in the skeleton of 3D graphene functions as a biofunctional component, which endows the TA-GH with good antibacterial capability.