A Polymer Dots-Based Photoelectrochemical pH Sensor: Simplicity, High Sensitivity, and Broad-Range pH Measurement

Area of Science:

• Electrochemistry
• Materials Science
• Nanotechnology

Background:

• Developing sensitive and stable pH sensors is crucial for bioanalytical applications.
• Traditional pH sensors face limitations in certain environments.
• Semiconducting polymer dots (Pdots) offer unique optoelectronic properties for sensing.

Purpose of the Study:

• To develop a novel photoelectrochemical (PEC) pH sensor.
• To utilize semiconducting polymer dots (Pdots) for sensitive and broad-range pH measurement.
• To explore the potential of Pdots in bioanalytical sensing.

Main Methods:

• Fabrication of a PEC pH sensor by immobilizing Pdots onto indium tin oxide (ITO).
• Investigation of Pdots' response to pH variations, including conformational changes and carrier diffusion.
• Analysis of photocurrent response alterations due to pH-induced changes in Pdots' redox properties.

Main Results:

• The developed sensor exhibited sensitive and variable photocurrent responses to different pH values.
• The carboxylic acid groups on Pdots were identified as key to pH sensitivity.
• The sensor demonstrated high sensitivity, stability, and reversibility.

Conclusions:

• The Pdots-based PEC sensor offers a promising platform for sensitive and broad-range pH measurements.
• The sensor's performance indicates significant potential for future applications in the bioanalytical field.
• The study highlights the utility of semiconducting polymer dots in electrochemical sensing.