Sensors (Jul 2021)

Fabrication and Characterization of Iridium Oxide pH Microelectrodes Based on Sputter Deposition Method

  • Ye Xi,
  • Zhejun Guo,
  • Longchun Wang,
  • Qingda Xu,
  • Tao Ruan,
  • Jingquan Liu

DOI
https://doi.org/10.3390/s21154996
Journal volume & issue
Vol. 21, no. 15
p. 4996

Abstract

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pH value plays an important role in many fields such as chemistry and biology; therefore, rapid and accurate pH measurement is very important. Because of its advantages in preparation, wide test range, rapid response, and good biocompatibility, iridium oxide material has received more and more attention. In this paper, we present a method for preparing iridium oxide pH microelectrodes based on the sputter deposition method. The sputtering parameters of iridium oxide are also studied and optimized. Open-circuit potential tests show that microelectrodes exhibit near-Nernstian pH response with good linearity (about 60 mV/pH), fast response, high stability (a slight periodic fluctuation of potential change <2.5 mV in 24 h), and good reversibility in the pH range of 1.00–13.00.

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