Colloidal InSb Quantum Dots Mid-Wave Infrared Photoconductive Detectors via One-Step Strong Acid Surface Treatment Strategy
Colloidal InSb quantum dots (QDs) hold significant promise in infrared photodetection. However, the current InSb QDs suffer from poor carrier mobility and limited spectral response (<1.8 μm) due to complex surface structure and high sensitivity to hydrolysis and oxidation. Here, we demonstrate one-step strong acid surface treatment strategy to simultaneously replace native insulating ligands and eliminate surface indium oxide. This dual-functional strategy achieves efficient surface passivation and enhances charge carrier transport, enabling InSb QDs films to exhibit an unprecedented hole mobility of 1.4 cm<sup>2</sup> V<sup>-1</sup> s<sup>-1</sup>. Notably, we report the first realization of a broadband InSb QDs infrared photoconductive detector with spectral sensitivity extending beyond 3 μm at room temperature. The device exhibits a specific detectivity of 4.7 × 10<sup>7</sup> Jones at 3.0 μm, representing the longest-wavelength interband photodetection based on lead/mercury-free QDs reported to date. This work manifests an important step toward room-temperature operable and heavy-metal-free QDs based mid-wave infrared photodetectors.
Authors
- Zifeng Liu (ORCID: https://orcid.org/0009-0005-5833-2141)
- Wenbo Lu (ORCID: https://orcid.org/0000-0001-8158-7947)
- Ning Dai (ORCID: https://orcid.org/0000-0002-6164-4331)
- Qingyu Wang (ORCID: https://orcid.org/0000-0002-3900-0425)
- Chenghua Sun (ORCID: https://orcid.org/0000-0001-7654-669X)
- Xiaoqi Hou (ORCID: https://orcid.org/0000-0002-5449-2034)
- Xingyu Hu (ORCID: https://orcid.org/0000-0002-7370-1196)
- Jun‐Jie Zhang (ORCID: https://orcid.org/0000-0002-4779-2725)
- Qing Li (ORCID: https://orcid.org/0000-0003-2019-3156)
- Yifan Chen (ORCID: https://orcid.org/0000-0001-7645-623X)
- Yang Li (ORCID: https://orcid.org/0000-0002-8907-5388)
- Zhe Liu (ORCID: https://orcid.org/0000-0001-9539-0184)
- Jiaqi Zhu (ORCID: https://orcid.org/0000-0003-0256-6924)
- H. J. You (ORCID: https://orcid.org/0009-0006-5056-4287)
- Bin Zeng
- Peixian Li (ORCID: https://orcid.org/0000-0001-5297-4964)
Institutions
- Zhejiang Lab (CN)
- Shanghai Institute of Technical Physics (CN)
- Institute for Advanced Study (DE)
- PATH To Reading (US)
- Infrared Laboratories (United States) (US)
- Changzhou University (CN)
- University of Chinese Academy of Sciences (CN)
- State Key Laboratory of Infrared Physics
Publication Details
- Journal
- Nano Letters
- Published
- 2025-08-26
- DOI
- https://doi.org/10.1021/acs.nanolett.5c03048
- Citations
- 5
- Primary Topic
- Quantum Dots Synthesis And Properties
- Type
- article
- Field-Weighted Citation Impact
- 2.59
Funders
- National Natural Science Foundation of China
- University of Chinese Academy of Sciences
- National Key Research and Development Program of China
- Basic Public Welfare Research Program of Zhejiang Province