▎ 摘　　要

NOVELTY - The synthesis of nitrogen-doped graphene aerogel involves ultrasonically dispersing oxidized graphene in deionized water, adding urea, stirring, hydrothermally reacting, heating, immersing in distilled water and freeze-drying to obtain nitrogen-doped graphene aerogel material, mixing nitrogen-doped graphene aerogel with pre-formulated polyvinyl alcohol solution to obtain paste-like dispersion, coating dispersion on hard paper and drying to obtain nitrogen-doped graphene aerogel paper electrode, preparing heavy metal ion solution and carrying out electrodeposition experiment. USE - Synthesis of nitrogen-doped graphene aerogel used for electro-adsorption of cadmium ions in wastewater. ADVANTAGE - The method enables synthesis of nitrogen-doped graphene aerogel with high heavy metal ions adsorption efficiency by simple and environmentally-friendly process. DETAILED DESCRIPTION - The synthesis of nitrogen-doped graphene aerogel involves (A) ultrasonically dispersing oxidized graphene in deionized water for 10-30 minutes, adding urea, mechanically stirring for 15 minutes, pouring the mixture into a hydrothermal reactor and heating in a muffle furnace at 180 degrees C for 12 hours, after the reaction, immersing the product in distilled water for 2-3 days and freeze-drying to obtain nitrogen-doped graphene aerogel material, (B) mixing the nitrogen-doped graphene aerogel with pre-formulated polyvinyl alcohol solution to obtain paste-like dispersion, evenly coating 0.1-0.4 ml of dispersion on hard paper and drying to obtain a nitrogen-doped graphene aerogel paper electrode, (C) preparing heavy metal ion solution, adding the heavy metal ion solution into electric adsorption vessel, carrying out electrodeposition experiment on gaseous nitrogen-gelled paper electrode, using three-electrode system for electro-adsorption of heavy metal ions, using paper electrode as working electrode, platinum sheet electrode as counter electrode and calomel electrode as reference electrode, using conductivity meter to monitor change of solution conductivity, when the conductivity remains constant, the adsorption of nitrogen-doped graphene aerogel paper electrode reaches equilibrium, and (D) after removing the voltage on the electrode, the conductivity of the solution is restored to near the initial value.