| 초록 |
The highly efficient all-polymer solar cells (all-PSCs) are fabricated without any solvent additives and thermal treatments by using naphthalene diimide (NDI) based alternating copolymer as electron acceptor. To control the planarity of polymer backbone, we introduced three different electron rich units. Particularly, the P(NDI-C) based on NDI and C exhibits the highest electron mobility (µe= 2.31 cm2 V-1 s-1) in organic-field effect transistors due to the enhanced degree of coplanarity. Also, the high µe value of P(NDI-C) facilitated charge transport in all-PSC blends, resulting in showing great hole/electron mobility balance (µh/µe). Thus, all-PSCs of PTB7-Th:P(NDI-C) exhibited high efficiency of 4.25% without any solvent additives or thermal treatments. Our results indicate that electron transport ability to the 3-dimensional direction of n-type polymer is one of the most important requirements for producing high-performance, additive-free all-PSCs. |
