A flexible IrO2 membrane for pH sensing
Shih-Cheng Chou1, Yi-Chieh Hsieh1, Wai-Hong Cheang1
1Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu, 300, Taiwan, ROC.
Scientific Reports
|July 9, 2022
Summary
This study developed a novel flexible pH sensor using iridium oxide nanoparticles on a functionalized polypropylene micromembrane. The sensor demonstrates a super-Nernstian response and stable performance, indicating potential for wearable electronics.
Area of Science:
- Materials Science
- Nanotechnology
- Sensor Technology
Background:
- Polypropylene micromembranes (PPMM) are typically hydrophobic.
- Developing flexible and sensitive pH sensors is crucial for wearable and implantable electronics.
Purpose of the Study:
- To create a hydrophilic and conductive PPMM for pH sensing.
- To evaluate the performance of iridium oxide (IrO2) nanoparticle-decorated PPMM as a flexible pH sensor.
Main Methods:
- Surface functionalization of PPMM with polydopamine (PDA) and polyvinyl alcohol (PVA).
- Electroless gold (Au) deposition followed by IrO2 nanoparticle coating.
- Characterization using scanning electron microscopy (SEM).
- Evaluation of pH-sensing performance in aqueous solutions (pH 2-12).
Main Results:
- Uniform IrO2 nanoparticle formation on Au-coated PP fibers confirmed by SEM.
- Achieved a super-Nernstian pH response with a slope of -74.45 mV/pH.
- Demonstrated stable sensing performance after 5000 bending cycles with modest hysteresis.
- Negligible bio-toxicity observed in cell viability tests.
Conclusions:
- The PDA/PVA functionalized and IrO2-decorated PPMM serves as an effective flexible pH sensor.
- The developed sensor shows promise for applications in wearable and implantable electronic devices.
- This strategy offers a new pathway for creating advanced conductive polymeric membranes for sensing.
