High performance sol-gel synthesized Ce0.9Sr0.1(Zr0.53Ti0.47)O4 sensing membrane for a solid-state pH sensor

Sankar Prasad Bag; Prabir Garu; Jim-Long Her; Bih-Show Lou; Tung-Ming Pan

doi:10.1039/c8ra03628d

High performance sol-gel synthesized Ce_0.9Sr_0.1(Zr_0.53Ti_0.47)O₄ sensing membrane for a solid-state pH sensor

RSC Adv. 2018 Jun 11;8(38):21210-21213. doi: 10.1039/c8ra03628d. eCollection 2018 Jun 8.

Authors

Sankar Prasad Bag¹, Prabir Garu¹, Jim-Long Her², Bih-Show Lou^{3

4}, Tung-Ming Pan^{1

5}

Affiliations

¹ Department of Electronics Engineering, Chang Gung University Taoyuan 33302 Taiwan tmpan@mail.cgu.edu.tw +886-3-2118507 +886-3-2118800 ext. 3349.
² Division of Natural Science, Center for General Education, Chang Gung University Taoyuan 33302 Taiwan.
³ Chemistry Division, Center for General Education, Chang Gung University Taoyuan 33302 Taiwan.
⁴ Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital Taoyuan 33302 Taiwan.
⁵ Division of Urology, Chang Gung Memorial Hospital Taoyuan 33302 Taiwan.

Abstract

In this paper, we developed a high-performance solid-state pH sensor using a Ce_0.9Sr_0.1(Zr_0.53Ti_0.47)O₄ (CSZT) membrane through a very simple sol-gel spin-coating process. The structural properties of the CSZT membrane are correlated with its sensing characteristics. The CSZT based EIS sensor exhibited a high pH sensitivity of 92.48 mV pH^-1, which is beyond the Nernst limit (59.4 mV pH^-1), and good reliability in terms of a low hysteresis voltage of 1 mV and a small drift rate of 0.15 mV h^-1. This behaviour is attributed to the incorporation of Sr in the CSZT sensing membrane, which promotes change in the Ce oxidation state from Ce⁴⁺ to Ce³⁺.