▎ 摘　　要

NOVELTY - Method for preparing crown ether functionalized graphene, involves (i) ultrasonically dispersing graphene oxide in ultrapure water under an ice bath to form a 1 mg/ml graphene oxide aqueous solution, adding an alkali solution and uniformly mixing to form a graphene oxide alkali solution, (ii) adding 0.3-3 mg/ml 1-aza-18-crown-6 ether and 0.5-1.5 mg/ml dopamine to the graphene oxide alkali solution, magnetically and uniformly stirring, heat-preserving at a constant temperature of 110-150 degrees C for 2-5 hours under a hydrothermal condition, adding a phase transfer catalyst and reacting at 85 degrees C for 10 hours, (iii) freezing and drying to obtain a freeze-dried product, and (iv) heating the product at 890 degrees C at a temperature rising rate of 18 degrees C/minute in an oxygen-free environment, heating and treating, naturally cooling, centrifugally washing and drying to obtain the product. USE - The method is useful for preparing crown ether functionalized graphene for detecting potassium ions. ADVANTAGE - The method adopts simple and cost-effective process under easy operation, is environmentally-friendly and realizes large-scale preparation.