Solution-processed Large Area Organic Solar Cells Materials and Devices

In the past few years, the performance of laboratory-scale organic solar cells (OSCs) have experienced very fast development, especially with the development of non-fullerene acceptor. However, there are still challenges on the way to realizing efficient module devices, such as the low compatibility of the thickness-sensitive interlayer and active layer with large area coating techniques, the tremendous power loss on enlarged electrode, the frequent need for toxic solvents, tedious optimization processes used during device fabrication, etc. To achieve high-performance large area PSC modules, we have carried out a series of studies. For the interlayer, we have developed simple and efficient approaches to achieving large area cathode interlayer using electrostatic layer-by-layer self-assembly and in situ self-assembly processes. N-type doping was also developed to obtain printable large area cathode interlayer. In terms of active layer, one of the main obstacles for printing ideal active layer comes from the excessive aggregation of film during printing. In this case, we have employed solvent engineering, third component strategy, molecular engineering and device structure engineering to overcome the excessive aggregation of active layer during printing and obtained high performance modules. On the basis of these results, non-halogen solvent dimethylbenzene processed large-area module with an active area of 18 cm(2) and efficiency over 14% was obtained. Finally, the existing problems and development directions of this field are discussed and forecasted. [GRAPHICS] .