I doped Mn into perovskite. I found when up to the best doping amount, the thin film PLQY much higher than the dispersion PLQY in my experiment. I don't know what caused it, is there any theory that can explain it?
Wang, J. T. W., Ball, J. M., Barea, E. M., Abate, A., Alexander-Webber, J. A., Huang, J., ... & Nicholas, R. J. (2014). Low-temperature processed electron collection layers of graphene/TiO2 nanocomposites in thin film perovskite solar cells. Nano letters, 14(2), 724-730.
Solid-state emission is higher in QDs cases where there is aggregation-induced emission (AIE). The aggregation is of J type or H-Type, and mostly J-type aggregates show a slight increase in Stokes shift and Quantum yield. I recommend you to study more about AIE.
Secondly, the solid-state emission is also thickness-dependent sometimes. Please make sure that the thickness of all films is equal.