Ultraviolet Photodetector Based on Poly(3,4-Ethylenedioxyselenophene)/ZnO Core-Shell Nanorods p-n Heterojunction

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Development of efficient ultraviolet (UV) photodetectors is crucial for various applications.
• Organic-inorganic hybrid materials offer unique properties for advanced optoelectronic devices.
• Zinc oxide (ZnO) nanoarrays (NRs) are promising semiconductor materials for UV detection.

Purpose of the Study:

• To fabricate and characterize an organic-inorganic core-shell hybrid p-n heterojunction UV photodetector.
• To investigate the structural and photodetection properties of the ZnO NRs/PEDOS composite.
• To evaluate the performance enhancement of the UV photodetector with the introduction of PEDOS.

Main Methods:

• Electropolymerization of poly(3,4-ethylenedioxyselenophene) (PEDOS) on ZnO NRs.
• Structural characterization using FTIR, UV-Vis, XRD, and XPS.
• Photodetection property analysis via current-voltage (I-V) and current-time (I-t) measurements.
• Mott-Schottky analysis to confirm the p-n heterojunction.

Main Results:

• Uniform growth of PEDOS on ZnO NRs, forming a core-shell structure.
• Formation of a p-n heterojunction with a strong built-in electric field.
• High responsivity (247.7 A/W), detectivity (3.41 × 10^12 Jones), and external quantum efficiency (84,000%) at 2 V.
• Significantly improved rise and fall times compared to bare ZnO UV photodetectors.

Conclusions:

• The ZnO NRs/PEDOS core-shell structure forms an effective p-n heterojunction for UV photodetection.
• The introduction of PEDOS substantially boosts the performance of ZnO-based UV photodetectors.
• This hybrid approach offers a promising pathway for developing high-performance UV optoelectronic devices.