▎ 摘　　要

NOVELTY - Preparation of graphene/bismuth composite material comprises dispersing 1-25 mmol/L water-soluble bismuth salt, 10-100 mmol/L graphene oxide and 1-25 mmol/L reducing agent in water to obtain mixed solution and heating. USE - Method for preparing graphene/bismuth composite material (claimed) used for modifying silk-screen printed electrode used in electrochemical sensor for detecting heavy metal ions (claimed). ADVANTAGE - The method is simple and environment-friendly. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for application of graphene/bismuth composite material comprising mixing graphene/bismuth composite material and Nafion (RTM: perfluoro-sulfonic acid polymer) at ratio of 20-200:1, coating on the silk-screen printed electrode and heating to dry.