Three p-type small molecules (CL-1–3) based on tetraphenylethylene as the core and different π-conjugation diarylamines as linkers are synthesized. The bilayer HTL of the NiOx/CL-3-based cell exhibits the best power conversion efficiency of 20.15%.
A new squaraine-based 2D conjugated polymer was developed as the donor material in polymer solar cells and dopant-free hole transporting material in inverted perovskite solar cells, reaching efficiencies of 6.35% and 18.29%, respectively.
Tetrafluoro-tetracyano-quinodimethane (F4TCNQ) was demonstrated to be an effective p-dopant for highly efficient PSCs based on P3HT as a hole-transporting material.