Triplet Sensitization Photon Upconversion Using Near-Infrared Indirect-Bandgap AgBiS<sub>2</sub> Nanocrystals
Colloidal semiconductor nanocrystals (NCs) have recently emerged as ideal triplet sensitizers owing to their diverse material composition and spectral tunability. However, the NCs that can efficiently sensitize near-infrared-to-visible photon upconversion remain largely limited to toxic lead-based NCs. Here, we present a new lead-free, near-infrared, indirect-bandgap sensitizer based on AgBiS<sub>2</sub> NCs, enabling near-infrared-to-yellow upconversion with a quantum yield reaching 10.5% (normalized to 100%). The key to success is the precise stoichiometry control of AgBiS<sub>2</sub> NCs, which provides the essential surface states for both radiative recombination and triplet energy transfer. Ultrafast transient absorption spectroscopy verifies the efficient triplet energy transfer mechanism mediated by surface states. Our work presents a new eco-friendly material system for efficient triplet fusion near-infrared photon upconversion.
Authors
- Wenfei Liang (ORCID: https://orcid.org/0000-0002-2860-4346)
- Kin Ting Chang
- Xihan Chen (ORCID: https://orcid.org/0000-0001-7907-2549)
- Shaokuan Gong
- Ping Fai Yeung
- Haipeng Lu (ORCID: https://orcid.org/0000-0003-0252-3086)
- Jianning Feng
Institutions
- Hong Kong University of Science and Technology (HK)
- Southern University of Science and Technology (CN)
Publication Details
- Journal
- Journal of the American Chemical Society
- Published
- 2025-04-09
- DOI
- https://doi.org/10.1021/jacs.5c04015
- Citations
- 13
- Primary Topic
- Luminescence Properties of Advanced Materials
- Type
- article
- Field-Weighted Citation Impact
- 6.73
Funders
- National Natural Science Foundation of China
- Research Grants Council, University Grants Committee
- Innovation and Technology Commission
- Hong Kong University of Science and Technology