摘要
Achieving high-performance as-cast OSCs is crucial for industrialization in the future,owing to the advantages of better stability,environmental-friendly,and decreasing production cost.In this regard,we synthesized an ADA′D-A type acceptor,Y6-eC6-BO,by shortening the straight alkyl side-chains on the thiophene position from C_(11) to C_(6) as well as lengthening the branched alkyl side-chains on the pyrrole position of Y6 to achieve a stronger crystallization and better miscibility than Y6.As a result,the corresponding chloroform-processed as-cast PM6:Y6-eC6-BO OSC showed a high PCE of 17.33%,which was one of the highest efficiencies of as-cast OSCs.And the as-cast PM6:Y6-eC6-BO OSCs processed from o-xylene displayed a PCE of 16.38%,as far as we know,this is among the highest efficiencies of non-halogenated-solvent processed as-cast OSCs.These results demonstrated tailoring the alkyl side-chain of NFAs is a feasible and simple approach to achieve high performance as-cast OSCs and provides guideline in molecular design in the future.
基金
Y.Zou acknowledges the National Natural Science Foundation of China(21875286 and 52125306)
the National Key Research and De velopment Program of China(2017YFA0206600)
X.Lu acknowledges the Research Grants Council of Hong Kong(14303519)。