Effect of ordered mesoporous carbon contact layer on the sensing performance of sputtered RuO2 thin film pH sensor

W Lonsdale; D K Maurya; M Wajrak; K Alameh

doi:10.1016/j.talanta.2016.11.020

Effect of ordered mesoporous carbon contact layer on the sensing performance of sputtered RuO₂ thin film pH sensor

Talanta. 2017 Mar 1:164:52-56. doi: 10.1016/j.talanta.2016.11.020. Epub 2016 Nov 15.

Authors

W Lonsdale¹, D K Maurya², M Wajrak³, K Alameh²

Affiliations

¹ Electron Science Research Institute, Edith Cowan University, Joondalup WA 6027, Australia. Electronic address: w.lonsdale@ecu.edu.au.
² Electron Science Research Institute, Edith Cowan University, Joondalup WA 6027, Australia.
³ School of Natural Sciences, Edith Cowan University, Joondalup WA 6027, Australia.

PMID: 28107967
DOI: 10.1016/j.talanta.2016.11.020

Abstract

The effect of contact layer on the pH sensing performance of a sputtered RuO₂ thin film pH sensor is investigated. The response of pH sensors employing RuO₂ thin film electrodes on screen-printed Pt, carbon and ordered mesoporous carbon (OMC) contact layers are measured over a pH range from 4 to 10. Working electrodes with OMC contact layer are found to have Nernstian pH sensitivity (-58.4mV/pH), low short-term drift rate (5.0mV/h), low hysteresis values (1.13mV) and fast reaction times (30s), after only 1h of conditioning. A pH sensor constructed with OMC carbon contact layer displays improved sensing performance compared to Pt and carbon-based counterparts, making this electrode more attractive for applications requiring highly-accurate pH sensing with reduced conditioning time.

Keywords: Contact layer; Ordered mesoporous carbon; PH sensor; R.F. sputtering; RuO(2).