High-quality white photoluminescence of zero-dimensional hybrid metal halides with multiple optical polyhedral units

Zero-dimensional organic-inorganic hybrid metal halides that can realize single-component white emission have attracted extensive attention due to the high-quality requirements of solid-state lighting technology. Although efficient white emission can be obtained in metal halides, the realization of tunable emission and high color rendering index of single-component white light remains a challenge. Herein, we report the binary halide (TEA)2(MnCl4)1-x (SbCl5)x (TEA+ = tetraethylammonium, C8H20N+), realizing warm white emission with a photoluminescence quantum yield of 86.24 %. (TEA)2(MnCl4)1-x (SbCl5)x halides with multiple optical polyhedral units ([SbCl5]2- pyramid and [MnCl4]2- tetrahedron) shows triple-peaked emission at 460 nm (free excitons emission), 520 nm (d–d transitions of Mn2+ ions), and 630 nm (self-trapped excitons emission). Interestingly, (TEA)2(MnCl4)1-x (SbCl5)x halides exhibit emission color tunability by changing excitation energy and temperature, respectively. A comparison of lifetime spectra, as well as the temperature-variation spectra, was utilized to elucidate the energy transfer mechanism between Sb3+ and Mn2+ ions. The single-component white light-emitting diode fabricated by (TEA)2(MnCl4)0.92(SbCl5)0.08 sample exhibits a high color rendering index of 92. This approach involving multiple emission mechanisms from different polyhedrons represents a promising avenue for designing single-component white-light emitters.