Triplet Sensitization Photon Upconversion Using Near-Infrared Indirect-Bandgap AgBiS₂ Nanocrystals.

ABSTRACT: 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 AgBiS₂ 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 AgBiS₂ 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 mech

SUBMITTER: Chang KT 

PROVIDER: S-EPMC12023030 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature