▎ 摘　　要

NOVELTY - Preparing nitrogen and sulfur co-doped graphene aerogel involves uniformly dispersing graphene oxide ultrasonically in deionized water for 10-30 minutes. The L-cysteine is added to the uniform dispersion with stirring, heated for 2 hours in water bath at a temperature of 95 degrees C. The reaction product, after completion of the reaction, is immersed in distilled water for 2-3 days, then freeze-dried to obtain nitrogen sulfur co-doped graphene airogel material. USE - Method for preparing nitrogen and sulfur co-doped graphene gel used as absorbing electrode for removing heavy metal ions from water (claimed). ADVANTAGE - The method enables to prepare nitrogen and sulfur co-doped graphene gel in simple, eco-friendly and cost-effective manner, that has high efficiency of adsorption of heavy metal ions in water. DETAILED DESCRIPTION - Preparing nitrogen and sulfur co-doped graphene aerogel involves uniformly dispersing graphene oxide ultrasonically in deionized water for 10-30 minutes. The L-cysteine is added to the uniform dispersion with stirring, heated for 2 hours in water bath at a temperature of 95 degrees C. The reaction product, after completion of the reaction, is immersed in distilled water for 2-3 days, then freeze-dried to obtain nitrogen sulfur co-doped graphene airogel material. The nitrogen sulfur co-doped graphene airogel is mixed with polyvinyl alcohol to form a dispersed paste, 0.1-0.4 milliliter dispersed paste is taken in pipette, evenly applied on the cardboard and freeze-dried to obtain nitrogen sulfur graphene airgel co-doped sheet electrode. The electrochemical method is carried out to remove heavy metal ions from water by preparing of heavy metal ions in solution. The amount of heavy metal ions in solution is placed in electrical adsorption vessel, where nitrogen sulfur co-doped graphene aerogel is used as working electrode. The three-electrode system is used, where nitrogen sulfur co-doped graphene aerogel is used as working electrode, platinum electrode as counter electrode and calomel electrode as reference electrode. The electrical conductivity meter is used for real-time monitoring of conductivity solution, when the conductivity remains same, the adsorption of each electrode has reached to equilibrium. The voltage on the electrodes is removed, after the completion of the process, and the conductivity of the solution is returned to nearly the initial value to achieve desorption electrode regeneration.