Sol-Gel Iridium Oxide-Based pH Sensor Array on Flexible Polyimide Substrate

Author

Nguyen, Cuong M. ; Wen-Ding Huang ; Rao, Smitha ; Hung Cao ; Tata, Uday ; Mu Chiao ; Jung-Chih Chiao

Author_Institution

Dept. of Electr. Eng., Univ. of Texas at Arlington, Arlington, TX, USA

Volume

13

Issue

10

fYear

2013

fDate

Oct. 2013

Firstpage

3857

Lastpage

3864

Abstract

Iridium oxide pH sensing film is demonstrated with wide pH-sensing ranges, high durability, and small drifts in potentials. Using sol-gel process, a lower fabrication cost and less labor-intensive method, to deposit iridium oxide thin films for pH sensing is reported previously by our group with expected advantages. In this paper, we fabricate and test pH sensing characteristics of 4 × 4 anhydrous iridium oxide thin-film electrode arrays on flexible substrates. The sensors in arrays exhibit Nernstian potential responses in the range of 57.0-63.4 mV/pH. Stability, repeatability, and hysteresis effects of the pH sensor arrays are examined. A multichannel recording system is built to demonstrate the functionality of the pH sensor arrays in monitoring spatial and temporal pH changes across a surface.

Keywords

chemical sensors; electrochemical electrodes; iridium compounds; pH measurement; polymers; sensor arrays; sol-gel processing; thin film sensors; IrO_x; Nernstian potential response; anhydrous iridium oxide thin-film electrode array; flexible polyimide substrate; hysteresis effect; labor-intensive method; multichannel recording system; sol-gel iridium oxide-based pH thin film sensor array; spatial pH monitoring; stability; temporal pH monitoring; Arrays; Calibration; Electrodes; Films; Sensitivity; Sensors; Substrates; Flexible substrate; iridium oxide; pH sensor; sensor array;

fLanguage

English

Journal_Title

Sensors Journal, IEEE

Publisher

ieee

ISSN

1530-437X

Type

jour

DOI

10.1109/JSEN.2012.2236551

Filename

6395238