A self-powered photodetector through facile processing using polyethyleneimine/carbon quantum dots for highly...

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Ultraviolet C (UVC) detection is crucial for human safety, environmental monitoring, and industrial applications.
• Solar-blind UVC detectors offer reduced interference from other environmental signals.
• Developing efficient and cost-effective UVC detection methods remains an active research area.

Purpose of the Study:

• To develop a self-powered, high-performance Ultraviolet C (UVC) photodetector.
• To utilize environmentally friendly and readily available materials for photodetector fabrication.
• To optimize photodetector performance by investigating film thickness and its effect on electron transport.

Main Methods:

• Preparation of carbon quantum dots (CQDs) from glucose via a one-step ultrasonic reaction.
• Fabrication of a polyethyleneimine (PEI)/CQD composite film for the photodetector.
• Systematic investigation of film thickness to optimize electron transport pathways and trap states.

Main Results:

• The developed PEI/CQD photodetector demonstrated a strong signal (1.5 mA W⁻¹ at 254 nm) and high detectability (1.8 × 10¹⁰ Jones at 254 nm).
• The photodetector exhibited an ultrafast response and long-term stability.
• Optimized film thickness significantly improved the performance of the UVC photodetector.

Conclusions:

• A novel, self-powered, solar-blind UVC photodetector was successfully fabricated using PEI and CQDs.
• The developed device offers an affordable, straightforward, and precise solution for UVC monitoring.
• This work highlights the potential of CQDs and PEI composites in advanced optoelectronic applications.