Air-stable inverted organic solar cells using TiO2 layer deposited by atomic layer deposition
We investigated the air-stable and highly efficient inverted organic solar cells (IOSCs) using TiO2 as electron selective layer prepared by an atomic layer deposition (ALD) method. Various thicknesses of TiO2 layer from 10 to 50 nm were adapted to confirm the thickness effect on device performance and stability. The IOSC with 20-nm-thick TiO2 layer showed the PCE of 3.01 % under AM 1.5 simulated illumination. Furthermore, the IOSCs showed better stability retaining over 80 % of the maximum PCE after 30 days. This suggests that IOSCs with TiO2 layer deposited by ALD gives a promising way for fabrication of air-stable organic solar cells.