Comprehensive Analytical Modelling of an Absolute pH Sensor
Cristina Medina-Bailon1, Naveen Kumar1, Rakshita Pritam Singh Dhar1
1Device Modelling Group, School of Engineering, University of Glasgow, Glasgow G12 8LT, UK.
Sensors (Basel, Switzerland)
|August 10, 2021
Summary
This study introduces an analytical model for absolute pH sensors, analyzing oxide degradation and proposing a dual capacitance method for accurate ion activity measurement. Hafnium dioxide shows improved stability over silicon dioxide.
Area of Science:
- Materials Science
- Analytical Chemistry
- Sensor Technology
Background:
- Oxide degradation impacts pH sensor performance.
- Measuring absolute ion activity remains a challenge.
Purpose of the Study:
- To develop an analytical model for absolute pH sensing.
- To investigate oxide degradation effects on sensor performance.
- To propose a method for absolute pH determination.
Main Methods:
- Derived analytical equations.
- Implemented numerical experiments in MATLAB.
- Utilized a dual capacitance system.
Main Results:
- Depletion width is pH-dependent.
- Hafnium dioxide exhibits smaller depletion width variations than silicon dioxide.
- A dual capacitance system can unequivocally determine acidity.
Conclusions:
- The proposed model and dual capacitance method enable absolute pH sensing.
- Hafnium dioxide offers superior stability against degradation compared to silicon dioxide.
Keywords:
analytical modeldepletion widthnano-biosensoroxide degradationpH sensor modelling and simulationsMore Related Videos
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