This paper reports the synthesis and characteristics of a series of alkyl-substituted planar polymers. The physical properties are carefully tuned to optimize their photovoltaic performance. Depending on the length of...This paper reports the synthesis and characteristics of a series of alkyl-substituted planar polymers. The physical properties are carefully tuned to optimize their photovoltaic performance. Depending on the length of soluble alkyl side chains which modify the structural order and orientation substantially in polymer backbones, the device performance can be improved significantly. The tuning of HOMO energy levels optimized polymers＇ spectral coverage of absorption and their hole mobility, as well as miscibility with fullerene; all these efforts enhanced polymer solar cell performances. The short- circuit current, Jsc for polymer solar cells was increased by adjusting polymer chain packing ability. It was found that films with well distributed polymer/fullerene interpenetrating network exhibit improved solar cell conversion efficiency. Enhanced efficiency up to 5.8% has been demonstrated. The results provide important insights about the roles of flexile chains in structure-property relationship for the design of new polymers to be used in high efficient solar cells.展开更多
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...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.展开更多
基金financially supported by the Postdoctoral Starting Foundation of Henan Normal University(01026500105)Young Scientists Foundation of Henan Normal University(01026400061)Henan Province basic and frontier technology research projects(1323004100247)
文摘This paper reports the synthesis and characteristics of a series of alkyl-substituted planar polymers. The physical properties are carefully tuned to optimize their photovoltaic performance. Depending on the length of soluble alkyl side chains which modify the structural order and orientation substantially in polymer backbones, the device performance can be improved significantly. The tuning of HOMO energy levels optimized polymers＇ spectral coverage of absorption and their hole mobility, as well as miscibility with fullerene; all these efforts enhanced polymer solar cell performances. The short- circuit current, Jsc for polymer solar cells was increased by adjusting polymer chain packing ability. It was found that films with well distributed polymer/fullerene interpenetrating network exhibit improved solar cell conversion efficiency. Enhanced efficiency up to 5.8% has been demonstrated. The results provide important insights about the roles of flexile chains in structure-property relationship for the design of new polymers to be used in high efficient solar cells.
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)。
文摘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.
