It is worth to note that, particularly for the PEA-based system, there is a specific 3D composition range of 40-60%, where the emergence of 3D-like phases becomes dominant while the other phases are greatly suppressed or are at the nominal level (Figure and). A similar trend was observed in the PEA-formamidinium (FA) quasi-2D HP systems; it was confirmed that vertically aligned 3D-like phases exclusively emerge at this compositional range, expected to benefit PV performances .