Work

Synergistic Interface Engineering via Buffer Layer and UVO Treatment for High‐Performance PbS Quantum Dot Near‐Infrared Photodiodes

Year: 2026

Type: article

Abstract: ABSTRACT While PbS quantum dot (QD) photodetectors exhibit promising near‐infrared (NIR) response, their performance is limited by interfacial defects and damage caused by ligand‐exchange processes. This study introduces a dual‐interface engineering strategy: (I) A solution‐processable Poly‐TPD buffer layer is inserted between the PbS‐halide active layer and PbS‐EDT hole transport layer to mitigate EDT/acetonitrile‐induced interfacial damage and improve hole extraction; (II) A controlled UV‐ozone treatment is applied to the PbS‐EDT layer to enhance p‐doping density and reduce defect states. The optimized device achieves a dark current density as low as 74 nA cm − 2 at ‐0.5 V, a responsivity of 0.42 A W −1 (at 1350 nm illumination), and a specific detectivity (D*) of 2.1 × 10 12 Jones, placing it among the higher‐performing solution‐processed PbS CQD photodiodes operating in the 1.3–1.4 µm range. This work provides a scalable approach for developing high‐performance solution‐processed NIR photodetectors.

Source: Advanced Science

DOI: 10.1002/advs.76271