Efficient Near-Infrared Luminescence in Lanthanide-Doped Vacancy-Ordered Double Perovskite Cs2ZrCl6 Phosphors via Te4+ Sensitization

All-inorganic lead-free perovskite-derivative metal halides have shown great promise in optoelectronics, however, it remains challenging to realize efficient near-infrared (NIR) luminescence in these materials. Herein, we report a novel strategy based on Te4+/Ln(3+) (Ln=Er, Nd, and Yb) co-doping to achieve efficient NIR luminescence in vacancy-ordered double perovskite Cs2ZrCl6 phosphors, which are excitable by a low-cost near-ultraviolet light-emitting diode (LED) chip. Through sensitization by the spin-orbital allowed S-1(0)-> P-3(1) transition of Te4+, intense and multi-wavelength NIR luminescence originating from the 4f -> 4f transitions of Er3+, Nd3+, and Yb3+ was acquired, with a quantum yield of 6.1 % for the Er3+ emission. These findings provide a general approach to achieve efficient NIR emission in lead-free metal halides through ns(2)-metal and lanthanide ion co-doping, thereby opening up a new avenue for exploring NIR-emitting perovskite derivatives towards versatile applications such as NIR-LEDs and bioimaging.

Automated summary

In this study, a novel strategy based on Te4+/Ln(3+) co-doping was reported to achieve efficient near-infrared luminescence in Cs2ZrCl6 phosphors. The findings provide a general approach to achieve efficient near-infrared emission in lead-free metal halides and open up a new avenue for exploring various applications such as near-infrared LEDs and bioimaging.