▎ 摘　　要

NOVELTY - The preparation of composite material involves (1) dispersing graphene oxide in water using Hummers method to prepare graphene oxide suspension, and (2) mixing glycine and silver nitrate with graphene oxide suspension using one-step hydrothermal method, where mass ratio of graphene oxide, glycine and silver nitrate is 1:2:1. USE - Preparation of three-dimensional graphene/silver composite material used as adsorbent for removing heavy metal such as mercury ion from water body (all claimed). ADVANTAGE - The method enables preparation of three-dimensional graphene/silver composite material having high adsorption capacity of heavy metals from water body, and the material is environmentally-friendly. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) three-dimensional graphene/silver composite material; and (2) application of three-dimensional graphene/silver composite material as adsorbent for water body for removing heavy metal such as mercury ion from water body.