Highly efficient visible and near-infrared luminescence of Sb3+, Tm3+ co-doped Cs2NaYCl6 lead-free double perovskite and light emitting diodes

Near-infrared (NIR) luminescent materials have been widely used in biomedicine, optical communication and other fields due to their unique photophysical properties. However, the development of efficient NIR luminescent materials is still a challenge. Herein, Sb3+, Tm3+ co-doped Cs2NaYCl6 double perovskite single crystals (SCs) have been synthesized. Benefiting from the crystal structure and rare earth lattice of rare earth-based double perovskite host, lanthanide ions can be doped effectively, and the optimal NIR photoluminescence quantum yield (PLQY) of Cs2NaYCl6:Sb3+, Tm3+ SCs is up to 20.2%. The energy transfer mechanism was systematically surveyed by steady-state spectroscopy. Furthermore, a compact visible and NIR light emitting diode was fabricated by coating Cs2NaYCl6:Sb3+, Tm3+ SCs on a commercial 320 nm LED chip. This light source has a promising application prospect in multifunctional lighting.