Red emission from clustered Mn2+ dopant in a tin-based perovskite semiconductor

Doping Mn 2+ brings in new energy levels to a variety of II-VI family and perovskite semiconductors. Although the Mn 2+ luminescence in most cases appears yellow to orange, photoexcitation of the tin-based perovskite material CsSn 0.9 Mn 0.1 Cl 3 (CTMC) leads to an unusual red emission at 647 nm. Characterizations using time-resolved photoluminescence (PL) and electron paramagnetic resonance (EPR) indicate that most of the Mn 2+ contents in CTMC are clustered like trimer chloromanganates, which accept photoexcitation energy from the perovskite matrix and acts as emission centers. These results are in sharp contrast from Mn 2+ -doped CsCaCl 3 or CsPbCl 3 , where individual Mn 2+ centers dominate the PL and EPR spectra . Our results provide a new approach to broadening the color range of Mn 2+ emission in perovskite semiconductors.