High-Performance Self-Powered Quantum Dot Infrared Photodetector with Azide Ion Solution Treated Electron Transport...

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Growing demand for self-powered photodetectors (PDs) in near-infrared (NIR) technologies like LIDAR.
• Lead sulfide quantum dot photodetectors (PbS QPDs) show promise for NIR detection but are limited by carrier traps and poor band alignment in ZnO NP ETLs.

Purpose of the Study:

• To improve the self-powered operation of PbS QPDs by addressing carrier traps and band alignment issues.
• To investigate the efficacy of an azide-ion treatment on ZnO NP ETLs for enhanced PbS QPD performance.

Main Methods:

• An effective azide-ion (N3-) treatment was applied to the ZnO NP electron-transport layer (ETL).
• Characterization of carrier lifetime, mobility, and internal electric field in the ZnO NP/PbS QD heterojunction.
• Performance evaluation of the treated PbS QPD under NIR illumination.

Main Results:

• Azide-ion treatment significantly reduced carrier traps and improved band alignment in the ZnO NP ETL.
• Enhanced carrier lifetime, mobility, and internal electric field were observed in the treated heterojunction.
• The azide-ion-treated PbS QPD achieved a responsivity of 0.45 A W⁻¹, detectivity of 4 × 10¹¹ Jones at 950 nm, response time of 8.2 µs, and a 112 dB linear dynamic range.

Conclusions:

• Azide-ion treatment is a viable strategy to enhance the performance of self-powered PbS QPDs.
• The improved PbS QPDs are suitable for advanced NIR applications requiring high sensitivity and fast response.
• This work offers a pathway for developing more efficient self-powered optoelectronic devices.