Effect of rotational speed variation with spin coating method on pH sensor performance based on Titanium Dioxide (TiO2)

The thick layer deposition of TiO
2
:AgCl on the alumina substrate by using spin coating method for pH sensor application has been conducted. A part of pH sensor of this design is electrode and sensing area, where the electrode material is AgCl and the sensing material in sensing area is TiO
2
. AgCl paste and TiO2 paste were made by mixing binder solution (PVA) with AgCl powder and TiO2 powder which mix with magnetic stirrer up to became homogenous paste. The AgCl material were deposed to alumina substrate at various rotational speed spin coating of 300 rpm, 500 rpm, 700 rpm, 1000 rpm and 1500 rpm. The TiO2 material was deposed on to alumina substrate at rotational speed spin coating 300 rpm. The result of sensor output voltage showed that the different rotational speed spin coating effect on the sensor output voltage. The sensor repeatability result showed that the sensor repeatable in certain condition. This proves that the materials used make the sensor ineffective for reusable sensors. The sensitivity result of 1000 rpm and 1500 rpm sensors, showed that the optimum sensitivity is 1000 rpm sensor with − 41.07 mV/pH. In the calculation of error analysis showed that the pH sensor has the best uncertainly at 1500 rpm with 0.5484%.