Applying a Novel Polymeric Precursor Derived by Capillary-Gravitational Coating in Fabrication of Nanostructured Tri- Metal Oxide-Based pH Sensing Electrode

In this study polymeric precursor (Pechini method) has been modified and utilized with purpose of fabricating tri-metal oxide pH sensing electrode. The method used in this research is unlike Pechini method, hence, propylene glycol used instead of ethylene glycol. pH sensing films were prepared using top candidates in the list of metal oxides that have been used in this field, such as IrO
_2,
RuO
₂
and TiO
₂
. New process called gravitational-capillary coating method applied to coat two different wire substrate (Ti and Steel). Synthesized electrodes characterized by SEM and X-ray diffraction, other related tests carried out. Suitable close Nernstian slope sensitivity -58.69 and -58.89 mV/pH have been observed, for titanium and steel electrodes respectively, acceptable stability, low hysteresis, insignificant rate of drift, short response time 3-3.5 sec with perfect selectivity have been estimated for both electrode.