| 초록 |
Polymer solar cells based on bulk heterojunction structure have been attracting a lot of attention because of the potential for low-cost, large-area, flexible and lightweight. As we known, benzodithiophene (BDT) unit is a novel conjugated polymers part. And we designed the structure with a new acceptor unit (TPP) which has alkoxyphenyl substituent on thienopyrroledione unit. Thus we synthesis and characterized two polymers OBDT-TPP and EBDT-TPP. OBDT-TPP with linear alkoxy side chain on BDT unit showed a power conversion efficiency (PCE) of 1.55%, while EBDT-TPP showed PCE of 2.07%. UV-visible absorption and cyclic voltammetry measurements reveal that the different side chins on BDT unit have little influences on the optical band gap and the energy levels of the polymers. The XRD studies and hole mobility measurement exhibited increased polymer crystallinity and hole carrier mobility in EBDT-TPP:PC71BM blends. Thus solar cell with EBDT-TPP achieved a higher PCE. |
