A general strategy via charge transfer sensitization to achieve efficient NIR luminescence in lanthanide-doped NaGdS2 nanocrystals

A strategy based on S²⁻-to-Yb³⁺ charge transfer sensitization is developed to achieve efficient NIR luminescence in Yb³⁺ singly-doped and Yb³⁺/Er³⁺ co-doped NaGdS₂ nanocrystals with quantum yields up to 21.2% and 25.0%, respectively.