Preparation and Optimization of Optical pH Sensor Based on Sol-Gel.

Area of Science:

• Materials Science
• Analytical Chemistry
• Chemical Engineering

Background:

• Traditional pH measurement methods often face limitations in specific applications.
• Development of advanced optical sensors offers potential for improved pH monitoring.

Purpose of the Study:

• To develop and optimize an optical pH sensor using the sol-gel technique.
• To evaluate the performance characteristics of the developed sensor compared to traditional methods.

Main Methods:

• Sol-gel technique utilizing tetraethyl orthosilicate (TEOS) and cellulose acetate.
• Incorporation of four pH indicators: congo red, bromophenol blue, cresol red, and chlorophenol red.
• Optimization of precursor ratios and membrane composition using orthogonal experiments.

Main Results:

• The optical pH sensor demonstrated a detection range of 2.5–11.0 pH.
• Achieved high measurement accuracy of up to 0.2 pH with excellent stability and repeatability.
• Support vector machine and linear regression were used for data analysis.

Conclusions:

• The sol-gel derived optical pH sensor exhibits superior performance compared to traditional pH glass electrodes.
• The developed sensor is a promising alternative for accurate and reliable pH measurements.
• Further optimization of the sensor composition can lead to enhanced performance characteristics.