Development of RuO2–TiO2 (70–30) mol% for pH measurements

A low cost pH electrode was prepared and characterized. A thin film of RuO2–TiO2 (70–30) mol% was prepared using the Pechini method and deposited on a Ti substrate. The slope of the potential versus pH curve is 56.03 mV pH−1 and the electrode is insensible to the presence of Li+, Na+ and Ca+ in the solution.