Host-sensitized Mn2+ doping for broadband luminescence from low-dimensional organic–inorganic hybrid cadmium chlorides

Low-dimensional organic-inorganic metal halides hold strong promise for optoelectronic device applications due to their exceptional tunable optical properties, strong quantum confinement leading to high exciton binding energy and radiative recombination, and solution processability. Herein, we report a Mn²⁺ doped one-dimensional cadmium chloride metal halide, Mn²⁺:(Bpe)Cd₂Cl₆ [Bpe = 1,2-bis(4-pyridyl)ethane], which exhibits a pronounced enhancement in metal-centered green emission upon Mn²⁺ incorporation into the host lattice. At a slightly higher doping level (3%), isolated Mn²⁺ ions contribute to a spin-forbidden ⁴T1(G) → ⁶A₁(S) transition at 620 nm, resulting in a greenish-orange dual emission with a substantial Stokes shift of approximately 100 nm. This work highlights the potential of host sensitization through Mn²⁺ doping in low-dimensional hybrid metal halides for achieving highly efficient and spectrally diverse luminescent materials, which are crucial for next-generation solid-state lighting and display applications.