| 초록 |
The modification of molecular structure like atomic substitution in polymer backbone have been proved to affect polymer band-gap, blend morphology, and device performance in PSCs. We synthesized new acceptor block having alkoxy-carboxylate group with an aim of achieving lower frontier energy levels and good solubility, and its D-A polymers. The compatibility of the new acceptor was systematically evaluated by comparing DFT calculations, Uv-vis analysis, molecular ordering, and nanoscale film morphologies in the resultant polymers. The optimized photovoltaic cells using the polymers P1 (2DEH-BDT) and P2 (2DSEH-BDT) showed PCE of 6.9 % and 6.2 %, respectively, with the non-fullerene acceptor ITIC. Our results demonstrated that the carboxylate substitution can be used as the alternate strategy to modulate the optoelectronic properties and control the aggregation in the conjugated polymers. |
