Electrochemical Impedance Study of Screen-printed Branch Structure Porous Carbon Electrode using MgO-templated Carbon and MgO Particle and its Application for Bilirubin Oxidase-immobilized Biocathode

Abstract

A porous carbon electrode with a branch structure composed of macropores and mesopores was prepared using MgO-templated carbon and MgO particles by screen-printing. The electrode characteristics were investigated using electrochemical impedance spectroscopy. Loci of the straight line with angles at 22.5° and 45° were observed in the high- and mid-frequency ranges, respectively. A partial semicircle appeared in the low-frequency range. The impedance analysis revealed that almost the entire charge-transfer reaction occurred only at the mesopore interface of the electrode. The current density of the bilirubin oxidase (BOD)-immobilized branch structure carbon electrode was 1.3 times higher than that of the BOD-immobilized non-branch structure carbon electrode.