▎ 摘　　要

NOVELTY - A hydroxypropyl cellulose/carbon nano tube/graphene modified electrode preparing method involves preparing graphene oxide composite material, dispersing graphene oxide in hydroxypropylcellulose SWNTs solution, mixing to form a uniform dispersion of reaction solution, adding urea, stirring, filtering, washing and drying to obtain hydroxypropyl cellulose/carbon nano tube/graphene composite material. The composite material is dispersed followed by polishing, rising, washing, washing, drying and coating composite material with glassy carbon electrode and drying to obtain the finished product. USE - Method for preparing a hydroxypropyl cellulose/carbon nano tube/graphene modified electrode for detecting heavy metal content such as cadmium ion (Cd2+), lead ion (Pb2+) and copper (Cu2+) (all claimed). ADVANTAGE - The method enables preparing the hydroxypropyl cellulose/carbon nano tube/graphene modified electrode with increased reaction site and increased specific surface area. DETAILED DESCRIPTION - A hydroxypropyl cellulose/carbon nano tube/graphene modified electrode preparing method involves preparing graphene oxide three-dimensional composite material with modified hummers method, dispersing graphene oxide in 1 mg/ml 0.1-1% hydroxypropylcellulose SWNTs solution according to the ratio of 3:1, 2:1, 1:1, 1:2, 1:3, mixing ultrasonically for 30 minutes to form a uniform dispersion of reaction solution, adding 1-5 mg urea, stirring uniformly in 200 ml tube at 120-180 degrees C for 4 hours, filtering, and washing with water and ethanol, and vacuum drying for 48 hours to obtain hydroxypropyl cellulose/carbon nano tube/graphene composite material. The obtained hydroxypropyl cellulose/carbon nano tube/graphene composite material is dispersed in 2-10 ml water, 0.2-1 mg/ml uniform dispersion liquid, ultrasonicated for 30 minutes, followed by polishing a glassy carbon electrode with phase sandpaper, and in turn polishing with polishing cloth and aluminum oxide, rising the electrode surface in water and ethanol, washing ultrasonically with water for 20 minutes, again washing with water and ethanol, drying at room temperature, and coating the composite material with glassy carbon electrode, and drying in infrared lamp to obtain the finished product. INDEPENDENT CLAIMS are also included for the following: (1) a hydroxypropyl cellulose/carbon nano tube/graphene modified electrode prepared by the method (2) a use of hydroxypropyl cellulose/carbon nano tube/graphene modified electrode for detecting heavy metal content.