Colloidal Mn-Doped Cesium Lead Halide Perovskite Nanoplatelets

Strong quantum confinement in Mn-doped semiconductor nanocrystals enhances dopant-carrier exchange interactions. Here, we report the synthesis and optical properties of strongly quantum confined, quasi two-dimensional, Mn-doped CsPbCI3 nanoplatelets. A room-temperature synthesis was employed to prepare the platelets with thickness 2.2 nm (4 monolayers), which is significantly smaller than the Bohr excitonic diameter of CsPbCI3 (5 nm). Efficient transfer of excitonic energy from the host to the Mia(2+) dopant ions leads to a spin-forbidden T-4(1)-(6)A(1) Mn d-electron emission with the highest quantum yield of similar to 20% and exhibits a long lifetime of 1.6 ms. Subsequent anion exchange reactions at room temperature lead to the formation of Mn-doped CsPbBr3 nano platelets, with weak Mn emission. These newly developed Mn-doped cesium lead halide nanoplatelets are suitable candidates for exploring the effects of quantum confinement on dopant carrier exchange interaction properties. and exhibiting interesting magneto-optic