All-Spray-Coated Inverted Semitransparent Organic Solar Cells and Modules

The aim of this study is to demonstrate a fabrication process of all-sprayed inverted organic photovoltaics. We sprayed the blend of poly(3-hexylthiophene-2,5-diyl) and [6, 6] phenyl-C
₆₁
-butyric acid methyl ester as an active layer and zinc oxide prepared by a sol-gel process as an electron transport layer. The highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) as a semitransparent anode and alternative to Ag is sequentially spray-coated. We further utilize nitrogen (N
₂
) plasma modification on the active layer for improving the compatibility between two layers in this work. With a combination of tuning the subsequent thermal treatment, the all-sprayed devices with good performance could be obtained. The highest power conversion efficiency (PCE) of 2.90% is achieved by optimizing the N
₂
plasma and thermal treatment, and the stability test is performed. Moreover, we up-scaled the all-spray-coating process to a module with three cells connected in series, and the PCE of the module is achieved to 2.44%.