Synergistic Interface Engineering via Buffer Layer and UVO Treatment for High-Performance PbS Quantum Dot
Chuan Wei1, Jun Han1, Ning Feng1
1School of Advanced Materials, Shenzhen Graduate School, Peking University, Shenzhen, P. R. China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|June 25, 2026
Summary
This study enhances lead sulfide quantum dot photodetectors for near-infrared detection. A dual-interface strategy improves performance by reducing defects and improving charge extraction, leading to higher detectivity.
Area of Science:
- Materials Science
- Nanotechnology
- Optoelectronics
Background:
- Lead sulfide quantum dots (PbS QDs) show potential for near-infrared (NIR) photodetectors.
- Interfacial defects and ligand-exchange damage limit PbS QD photodetector performance.
- Improving interfacial engineering is crucial for high-performance NIR photodetectors.
Purpose of the Study:
- To develop a dual-interface engineering strategy for solution-processed PbS QD photodetectors.
- To mitigate interfacial damage and enhance hole extraction in PbS QD devices.
- To improve p-doping and reduce defect states in the PbS-EDT layer.
Main Methods:
- Insertion of a Poly-TPD buffer layer between PbS-halide and PbS-EDT layers.
- Application of controlled UV-ozone treatment to the PbS-EDT layer.
- Fabrication and characterization of optimized PbS QD photodetectors.
Main Results:
- Achieved a low dark current density of 74 nA cm-2 at -0.5 V.
- Obtained a responsivity of 0.42 A W-1 at 1350 nm.
- Reached a specific detectivity (D*) of 2.1 × 1012 Jones in the 1.3-1.4 µm range.
Conclusions:
- The dual-interface strategy effectively reduces interfacial defects and damage.
- Optimized PbS QD photodetectors demonstrate high performance for NIR detection.
- This scalable approach enables development of advanced solution-processed NIR photodetectors.
