Layered Perovskites L₂(Pb_1–xMn_x)Cl₄ to Mn-Doped CsPbCl₃ Perovskite Platelets

Doped perovskite nanocrystals have recently emerged as a new class of energy materials for solar concentrators and solid-state lighting device applications. Among these, doping Mn(II) in high band gap CsPbCl3 perovskite host nanostructures has been extensively studied. However, going beyond their optical emissions, herein, the impact of dopant ions on tuning the doped platelet dimensions and retaining the monodispersity is reported. These were performed by designing appropriate compositions of layered perovskites, L2(Pb1–xMnx)Cl4, which on thermal treatment in the presence of Cs(I) ions transformed to Mn-doped CsPbCl3 platelets. Correlating the amount of Mn present in layered perovskites and retained in doped platelets, the role of Mn for the conversion of layered to doped perovskites was established. These doped platelets showed dominated Mn d–d emission and also Mn concentration-dependent emission tuning. Even though several reports of Mn-doped CsPbCl3 have been reported, these findings add new fundamental insight into the design of dimension-tunable doped perovskites from layered perovskites.