Mn²⁺/Yb³⁺ Codoped CsPbCl₃ Perovskite Nanocrystals with Triple-Wavelength Emission for Luminescent Solar Concentrators

Doping metal ions into lead halide perovskite nanocrystals (NCs) has attracted great attention over the past few years due to the emergence of novel properties relevant to optoelectronic applications. Here, the synthesis of Mn²⁺/Yb³⁺ codoped CsPbCl₃ NCs through a hot-injection technique is reported. The resulting NCs show a unique triple-wavelength emission covering ultraviolet/blue, visible, and near-infrared regions. By optimizing the dopant concentrations, the total photoluminescence quantum yield (PL QY) of the codoped NCs can reach ≈125.3% due to quantum cutting effects. Mechanism studies reveal the efficient energy transfer processes from host NCs to Mn²⁺ and Yb³⁺ dopant ions, as well as a possible inter-dopant energy transfer from Mn²⁺ to Yb³⁺ ion centers. Owing to the high PL QYs and minimal reabsorption loss, the codoped perovskite NCs are demonstrated to be used as efficient emitters in luminescent solar concentrators, with greatly enhanced external optical efficiency compared to that of using solely Mn²⁺ doped CsPbCl₃ NCs. This study presents a new model system for enriching doping chemistry studies and future applications of perovskite NCs.