Effect of Dual Cathode Buffer Layer on Ternary Organic Solar Cell

Effect of cathode interfacial layer namely, BCP and BPhen on ternary organic solar cell using P3HT, PC
₇₁
BM with CPDT derivative, BH-1, was investigated and compared with the conventional LiF/Al structure. The doping concentration of the BH-1 in P3HT: PC
₇₁
BM blend was systematically standardized from UV-Vis absorption study. The device with ITO/PEDOT: PSS/P3HT: BH-1: PC71BM/BCP/LiF/Al configuration showing the best performance with PCE, η=3.23%, J
_sc
=12.33 mA/cm
²
, V
_oc
= 0.54 V and FF=48.10% due to the less recombination at the cathode interface. These results systematically explain the role of dual cathode buffer layer to reduce the S-factor in performance of ternary BHJ solar cell.