Abstract
Diminishing surface defect states in perovskite nanocrystals is a highly challenging subject for enhancing optoelectronic device performance. We synthesized organic/inorganic lead-halide perovskite MAPbBr3 (MA = methylammonium) clusters comprising nanocrystals with diameters ranging between 20–30 nm and characterized an enhanced photoluminescence (PL) quantum yield (as much as ~ 7 times) by encapsulating the MAPbBr3 with graphene (Gr). The optical properties of MAPbBr3 and Gr/MAPbBr3 were investigated by temperature-dependent micro-PL and time-resolved PL measurements. Density functional theory calculations show that the surface defect states in MAPbBr3 are removed and the optical band gap is reduced by a 0.15 eV by encapsulation with graphene due to partial restoration of lattice distortions. [Figure not available: see fulltext.].
Original language | English |
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Pages (from-to) | 932-938 |
Number of pages | 7 |
Journal | Nano Research |
Volume | 13 |
Issue number | 4 |
DOIs | |
State | Published - 1 Apr 2020 |
Keywords
- density functional theory calculations
- graphene
- perovskite nanocluster
- photoluminescence
- surface passivation