Polymer film modified electrode and preparation method and application thereof

The invention belongs to the technical field of electroanalytical chemistry, and discloses preparation of a bismuth film/polydibromo fluorescein modified electrode and a method for determining the concentration of Cd < 2 + > in farmland irrigation water. The preparation process of the modified electrode comprises the following steps: electrochemically polymerizing dibromo fluorescein molecules tothe surface of a glassy carbon electrode through cyclic voltammetry to prepare a polydibromo fluorescein membrane chemically modified electrode (recorded as Poly (DBF)/GCE), and then adding a proper amount of bismuth ions to prepare a bismuth membrane/polydibromo fluorescein membrane modified electrode (Bi/Poly (DBF)/GCE) through adsorption. By utilizing the modified electrode, a novel, sensitive,accurate and simple electrochemical method is established to determine the trace Cd < 2 + > in a water sample through anodic stripping differential pulse voltammetry. 本发明属于电分析化学技术领域，本发明公开了一种铋膜/聚二溴荧光素修饰电极的制备及测定农田灌溉水中Cd2+浓度的方法。