Tri-System Interlocking Top-Encased Structures Enabled Highly Stable Tin-Lead Perovskite Photodetection Arrays

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Tin-lead perovskites offer broad spectral bandwidth (UV-NIR) for photodetection.
• Divalent tin oxidation leads to vacancies and defects, reducing device efficiency and stability.

Purpose of the Study:

• To improve the efficiency and stability of tin-lead perovskite photodetectors using a cost-effective additive.
• To investigate the role of chlorogenic acid in defect suppression and energy-level alignment.

Main Methods:

• Utilized chlorogenic acid, a natural reducing agent, as an additive without costly synthesis.
• Developed a top-encased tri-system interlocking structure in tin-lead perovskites.
• Investigated synergetic interactions between chlorogenic acid functional groups and perovskites.

Main Results:

• Enhanced tin-lead perovskite photodetectors (PDs) with improved energy-level alignment, antioxidation, and defect passivation.
• Achieved self-powered near-infrared (NIR) PDs with high external quantum efficiency (≈76%) and specific detectivity (2 × 10^13 Jones at 940 nm).
• Demonstrated a large linear dynamic range (222 dB) and excellent stability (96% photocurrent retention after 127 days).
• Integrated PDs with a 64 × 64 thin-film transistor array for clear and accurate imaging sensor applications.

Conclusions:

• Chlorogenic acid effectively enhances tin-lead perovskite optoelectronic properties and stability.
• The developed perovskite photodetectors and image sensors show significant potential for high-detectivity and high-resolution imaging applications.