An Integrated Solid-State pH Microelectrode Prepared Using Microfabrication. (10th January 2015)

• Record Type: Journal Article
• Authors: Chu, Jian; Zhao, Yue; Li, Shu-Hong; Yu, Han-Qing; Liu, Gang; Tian, Yang-Chao
• Is Part Of: Electrochimica acta. Volume 152(2015)
• Page Start: 6
• Page End: 12
• Publication Date: 2015-01-10
• Subjects: pH microelectrode -- microfabrication -- electrochemical modification -- biofilm; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2014.11.102
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: An integrated solid-state pH microelectrode was efficiently and conveniently fabricated. The electrode had a good linear relationship in pH of 1.56–12.00, and had high stability, reproducibility and long lifetime. The electrode was successfully detect the pH distribution within the biofilm of a microbial fuel cell. Abstract: Integrated pH microelectrodes, which overcome the size limitations of reference electrode and counter electrode, are highly desired for in vivo or in situ microscale measurements. In this work, an innovative integrated solid-state pH microelectrode (ISP) was fabricated using microfabrication technique in combination with electrochemical modification. The as-prepared ISP consisted of a solid-state IrO2 pH microelectrode, an Ag/AgCl reference microelectrode, a gold counter microelectrode, and two spare gold microelectrodes. Its electrochemical performance was characterized by open-circuit potential and cyclic voltammetry. The long-term stability of IrO2 pH microelectrode and the interference of Cl − concentrations on the Ag/AgCl reference microelectrode were also evaluated. In addition, the ISP was used to measure the spatial pH distributions within the biofilm on the proton-exchange membrane surface of a microbial fuel cell. The results show that the ISP had high stability, reproducibility and long lifetime, demonstrating a great potential of such a microelectrode for in situ electrochemical measurement of pH distribution at microscale.