Yin, Jun Yang, Haoze Song, Kepeng El-Zohry, Ahmed M. Han, Yu Bakr, Osman M. Brédas, Jean-Luc Mohammed, Omar F. Point Defects and Green Emission in Zero-Dimensional Perovskites Zero-dimensional (0D) perovskites have recently opened a new frontier in device engineering for light conversion technologies due to their unprecedented high photoluminescence quantum yield as solids. Although many experimental and theoretical efforts have been made to understand their optical behavior, the origin of their green emission is still opaque. Here, we develop a complete experimental and theoretical picture of point defects in Cs–Pb–Br perovskites and demonstrate that bromide vacancies (V<sub>Br</sub>) in prototype 0D perovskite Cs<sub>4</sub>PbBr<sub>6</sub> have a low formation energy and a relevant defect level to contribute to the midgap radiative state. Moreover, the state-of-the-art characterizations including atomic-resolution electron imaging not only confirm the purity of the 0D phase of Br-deficient green-emissive Cs<sub>4</sub>PbBr<sub>6</sub> nanocrystals (NCs) but also exclude the presence of CsPbBr<sub>3</sub> NCs impurities. Our findings provide robust evidence for defect-induced green luminescence in 0D perovskite NCs, which helps extend the scope of the utility of these bulk 0D quantum materials in optoelectronic applications. bulk 0 D quantum materials;atomic-resolution electron imaging;V Br;prototype 0 D perovskite Cs 4 PbBr 6;CsPbBr 3 NCs impurities;point Defects;0 D phase;light conversion technologies;midgap radiative state;formation energy;Br-deficient green-emissive Cs 4 PbBr 6 nanocrystals;defect level;photoluminescence quantum;optoelectronic applications;device engineering;bromide vacancies;Green Emission;point defects;0 D perovskite NCs 2018-09-05
    https://acs.figshare.com/articles/journal_contribution/Point_Defects_and_Green_Emission_in_Zero-Dimensional_Perovskites/7069808
10.1021/acs.jpclett.8b02477.s002