| 초록 |
We report a novel non-conjugated polymer additive (nPA), poly(2-vinylpyridine) (P2VP), for modifying the interfaces between bulk-heterojunction (BHJ) and cathode/metal oxide (MO) layers. The P2VP nPA enables remarkably enhanced power conversion efficiencies (PCEs) and ambient stability in different types of polymer solar cells (PSCs). Importantly, the interfacial engineering can be achieved during the deposition of the P2VP nPA added BHJ active layer via simple, one-step solution processing. The P2VP nPA has much higher surface energy than the BHJ active components and stronger interaction with the surface of the metal oxide (MO). Thus, a spontaneous vertical-phase separation from the BHJ layer on the MO surface can be achieved by one-step solution processing. The self-assembled P2VP layer substantially reduces the work function and surface defect density of MO, thereby minimizing the charge-extraction barrier and increasing the PCEs of the PSCs significantly. |
