Efficient and flexible ITO-free organic solar cells using highly conductive polymer anodes

A study was conducted to demonstrate the fabrication of an indium tin oxide (ITO)-free organic solar cell, with high efficiency and better flexibility, using an organic-based electrode material to replace ITO. The study focused on demonstrate ITO-free OSCs that are fabricated on glass and flexible plastic substrates. It was observed that the efficiency of the cells was comparable to that of that of ITO-based devices fabricated on glass and on flexible substrates under equivalent conditions. The efficiency of ITO-free OSCs with PEDOT anodes remained unchanged after more than 300 bending cycles, while ITO-based cells on flexible substrates showed a power conversion of 0%, after 75 bending cycles during the flexibility test. Conductivity of the cells was evaluated, using four-point-probe measurement obtained for a series of PEDOT:PSS and ITO films.