Conducting poly(3,4-ethylenedioxythiophene):poly(styrene- sulfonate) film electrode with superior long-term electrode stability in water and synergistically enhanced electrocatalytic ability for application in electrochemical sensors

Abstract

A novel poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) composite film with superior stability in water, adhesion and flexibility, which is very critical for maintaining the long-term stability in water of the PEDOT:PSS film electrode, was easily prepared by introducing a water-soluble, anionic, non-toxic and biocompatible biopolymer (sodium carboxymethyl cellulose, Na-CMC) into a commercially available aqueous dispersion of the conducting polymer (PEDOT:PSS dispersion). The high conducting PEDOT:PSS-CMC film exhibited good flexibility and long-term stability in water after being soaked in water for 35 days. The high performance film electrode with excellent adhesion, long-term electrode stability in water (retaining almost 99.4% of its original activity for 105 days), and electrochemical properties was prepared facilely by drop-coating, and displayed good synergistically enhanced electrocatalytic ability towards the anodic oxidation of harmful substances and nutritional ingredients in edible agro-products, which were employed for its application in electrochemical sensors. The simultaneous or individual detection of maleic hydrazide, salicylic acid, nitrite, sunset yellow, and tryptophan was successfully realized using PEDOT:PSS-CMC/GCE, and exhibited superior sensing stability. All satisfactory results indicated that the introduction of CMC into PEDOT:PSS could improve the flexibility, adhesion, long-term electrode stability in water and electrocatalytic ability, which would provide a promising platform for the application in electrochemical fields of the high performance film electrode, especially the application in electrochemical sensors.