A Solution-Based Deposition Method Enabling Pigment Blue Edible Electrochemical Transistors

Area of Science:

• Materials Science
• Organic Electronics
• Biomedical Engineering

Background:

• Copper(II) phthalocyanine (CuPc), or Pigment Blue 15, is a semiconductor with potential for edible electronics.
• Edible devices require safe, low-voltage transistors with high transconductance for in-body applications like gastrointestinal monitoring.

Purpose of the Study:

• To develop a simple, cost-effective method for producing solution-processed CuPc films with a porous microstructure.
• To evaluate the performance of electrolyte-gated transistors fabricated with these porous CuPc films for edible electronics.

Main Methods:

• Solution processing of CuPc to create porous films with enhanced volumetric ion uptake.
• Fabrication and characterization of electrolyte-gated transistors using the porous CuPc films.
• Comparison of performance metrics (capacitance, On/Off ratio, transconductance) with conventionally produced films.

Main Results:

• Porous CuPc films exhibited 30 times greater capacitance than compact films.
• Edible transistors achieved On/Off ratios > 10^3 and transconductance up to 50 µS mm⁻¹ at 0.8 V.
• The method showed limited impact of impurities, reducing purification costs and enabling pigment recycling.

Conclusions:

• The developed method yields high-performance porous CuPc films suitable for edible electronic transistors.
• These transistors are promising active components for advanced gastrointestinal tract monitoring devices.
• The approach supports cost reduction and sustainability through pigment recycling and upcycling.