| 초록 |
A new series of alkyl-modified narrow bandgap non-fullerene small molecule acceptor (NFSMA) isomers are synthesized and characterized to figure out the influence of substitution position. By introducing the electron-donating alkyl group, elevated the lowest unoccupied molecular orbital (LUMO) results in higher open-circuit voltage (Voc) with the wide band gap polymer donor. Not only this, optical, thermal, and electrochemical properties are also changed and resulted in the increase of short-circuit current density (Jsc) and fill factor (FF). The optimum power conversion efficiency (PCE) of 10.26% for alkyl-modified SMA can be obtained by use of polymer poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophen)-co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)benzo[1,2-c:4,5c′]dithiophene-4,8-dione)] (PBDB-T) as an electron donor without any additive. The morphologies of blends and packing structure can be modulated by the position of end group substitution. |
