Achieving versatile optoelectronic applications of environment-friendly halide double perovskite by multi-ion codoping strategy

Lead-free halide double perovskites (DPs) have been regarded as a class of environmentally friendly and promising optoelectronic materials. Herein, we report the synthesis, luminescence properties, and optoelectronic applications of lanthanide (Ln = Yb 3+ /Er 3+ )/M (M = Bi 3+ /Sb 3+ /Mn 2+ ) codoped Cs 2 NaInCl 6 single crystals (SCs). The Yb/Er codoped Cs 2 NaInCl 6 SCs show upconversion and downshifting visible/short-wave infrared (SWIR) photoluminescence emission. After further introduction of Sb 3+ /Mn 2+ ions into the host, bright blue and red emissions are observed with the PLQYs of 96.28% and 21.58%, respectively. With the incorporation of Bi 3+ ions, the upconversion and visible/SWIR luminescence intensities of Yb/Er/Bi codoped Cs 2 NaInCl 6 SCs are significantly enhanced. The incorporation of Bi 3+ dopant in the DP host can construct a more efficient energy transfer process, resulting in excellent luminescence efficiency. The multi-ion codoped DP system exhibits great potential for optoelectronic applications in the fields of anticounterfeiting, photodetector, and x-ray imaging. This work will help guide the design and development of environmentally friendly multi-functional materials.