My structure is ITO/PCBM/Perovskite/HTL/Electrode
I am using 20mg PCBM and 1:1.1 PbI2 and MAI In DMF and DMSO (7:3)..
But when i coat perovskite on the top of PCBM it Dewett the PCBM and only middle side of the cell has been covered with perovskite and sides of the cell are completely dewetted..
Even at the sides of cell there is no PCBM..
I tried many things using different filters without filter spin casting drop casting but did not get satisfactory result..
Kindly let me know what is the issue and how it can be solved