Doping Mn²⁺ in hybrid Ruddlesden–Popper phase of layered double perovskite (BA)₄AgBiBr₈

The layered hybrid double perovskites emerged as excellent semiconductor materials owing to their environment compatibility and stability. However, these materials are weakly luminescent, and their photoluminescence (PL) properties can be modulated via doping. While Mn2+doping in perovskites is well known, but to the best of our knowledge the doping of Mn2+in layered double perovskites (LDPs) is yet to be explored. Herein, for the first time, we demonstrate the doping of Mn2+in hybrid inorganic-organic two-dimensional (2D) LDPs, (BA)4AgBiBr8(BA = n-butyl amine) via a simple solid-state mechanochemical route. The powder x-ray diffraction pattern, and electron paramagnetic resonance analysis confirm the successful incorporation of Mn2+ions inside (BA)4AgBiBr8lattice. The Mn2+doped 2D LDP shows energy transfer from host excitons to d-electrons of Mn2+ions, which results in red-shifted broad Mn2+emission band centered at 625 nm, attributed to thespin-forbidden4T1to6A1internal transition. This work opens up new possibilities to dope metal ions in 2D LDPs to tune the optical as well as magnetic properties.