High-Performance Green Emission from Mn²⁺-Doped 0D OIHMH Crystals for White LEDs and Anti-Counterfeiting Applications

The exploration of novel phosphors with excellent properties is of great significance for both fundamental research and practical applications in optoelectronic devices. In this study, we report the synthesis of a new 0 dimensional (0D) organic-inorganic hybrid metal halide (OIHMH), C6H14N2ZnCl4, upon doping with Mn²⁺ ions, it exhibits bright green emission centered at 535 nm, originating from the d-d transition of tetrahedrally coordinated Mn²⁺ ions. The sample achieve photoluminescence quantum yields (PLQYs) of 70% at a doping concentration of 40% and demonstrate good thermal stability, with luminescence intensity restored after a heating-cooling cycle. The as-prepared Mn²⁺-doped C6H14N2ZnCl4 crystals were further utilized to fabricate white light-emitting diodes (WLEDs), which demonstrated good performance with a correlated color temperature (CCT) of 6003 K and a color rendering index (CRI) of 79. Additionally, the bright green emission of the doped crystals was explored for anti-counterfeiting applications, showing promising potential in security marking. This work highlights the potential of Mn²⁺-doped OIHHPCs as high-performance phosphors for optoelectronic applications and security purposes.