Formation of highly crystalline and texturized donor domains in DPP(TBFu)2:PC71BM SM-BHJ devices via solvent vapour annealing: implications for device function

摘要: Solvent vapour annealing (SVA), which consists of exposing the active layer organic films to a solvent directly after deposition, has been used in small molecule bulk heterojunction (SM-BHJ) solar cell devices whose consisted 3,6-bis(5-(benzofuran-2-yl)thiophen-2-yl)-2,5-bis(2-ethylhexyl)pyrrolo[3,4-c]pyrrole-1,4-dione (DPP(TBFu)2) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM). We demonstrate that upon SVA, well-ordered crystalline domains DPP(TBFu)2 donor form inside layer, improving greatly Fill Factor (FF) devices. However, SVA treatment is always accompanied by decrease device short circuit current (JSC). demonstrate, using 1D 2D XRD AFM, matrix PC71BM acceptor. The crystallinity increases with time (ta) change FF JSC linked this. X-ray single crystal structure was solved provided information donor's packing solid state. molecules were shown pack herringbone arrangement highly texturized film. demonstrated ability large as equally determining for devices' characteristics individual stacking properties