▎ 摘　　要

NOVELTY - Preparing electrode involves preparing polyimide layer on substrate, and irradiating substrate with ultraviolet laser to obtain electrode for detecting nitrite comprising nitrogen and oxygen co-doped graphene. USE - Method for preparing electrode that is used for preparing sensor for detecting nitrite (claimed). ADVANTAGE - The sensor has high sensitivity and selectivity for detecting nitrite, high response speed and high repeatability, and has good application value in the aspect of fast detection of nitrite. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: 1. an electrode for detecting nitrite prepared by the preparation method; and 2. a method for preparing sensor for detecting nitrite, which involves: using electrode to obtain an electrode comprising nitrogen and oxygen co-doped graphene, and encapsulating the electrode comprising nitrogen and oxygen co-doped graphene.