Highly efficient and stable organic solar cell modules processed by blade coating with 5.6% module efficiency and active area of 216 cm ²

In this study, an efficient and stable large-area blade-coated organic solar cell (OSC) module with an active area of 216 cm ² (16 elementary cells connected in series) is demonstrated by combining appropriate thermal annealing treatment with the use of 4,4′-(((methyl(4-sulphonatobutyl)ammonio)bis(propane-3,1-diyl))bis(dimethyl-ammoniumdiyl))bis-(butane-1-sulfonate) (MSAPBS) as the cathode interfacial layer. For the opaque device using poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b′]dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl)] (PBDTTT-EFT (PTB7-Th)):[6,6]-phenyl C ₇₁ -butyric acid methyl ester (PC ₇₁ BM) blend film as the active layer, the power conversion efficiency (PCE) of 5.6% is achieved under AM 1.5G solar light illumination. Very encouragingly, our strategy can be applicable for semitransparent OSCs, and a remarkable PCE up to 4.5% is observed. To the best of our knowledge, the PCE of 5.6% for opaque device and 4.5% for semitransparent device represent the highest PCE ever reported for OSCs with the active area exceeding 100 cm ² . The devices also show an impressive stability under outdoor environment, where the efficiency decay is less than 30% for 60 days. Our findings can pave the way toward the development of organic solar cell modules with high performance and long-term stability.