Self-Powered Deep-Ultraviolet Photodetector Driven by Combined Piezoelectric/Ferroelectric Effects.

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Photodetectors (PDs) are crucial for UV detection.
• Developing self-powered and highly sensitive PDs remains a challenge.
• Piezoelectric materials offer potential for enhancing photodetector performance.

Purpose of the Study:

• To develop a self-powered deep-ultraviolet photodetector.
• To leverage in situ piezoelectricity for improved photocarrier dynamics.
• To explore the use of PVDF@Ga2O3 and PEI/CQDs in photodetector fabrication.

Main Methods:

• Fabrication of a ferroelectric composite layer using β-Ga2O3 filler and β-phase PVDF matrix.
• Incorporation of piezoelectricity into the photoactive region of the photodetector.
• Characterization of the photodetector's performance, including detectivity, on/off ratio, and response speed.

Main Results:

• The self-powered PD achieved a specific detectivity of 3.5 × 10^10 Jones.
• An on/off ratio of 2.7 and a response speed of 0.11/0.33 s were recorded.
• The device demonstrated excellent photoresponse stability, retaining 83% photocurrent after 500s of UV irradiation.

Conclusions:

• The piezoelectric effect in β-PVDF effectively enhances photocarrier separation and transport.
• The developed photodetector offers a promising, cost-effective solution for optoelectronic applications.
• This work presents a novel strategy for designing high-performance, self-powered UV photodetectors.