Influence of Molecular Geometry of Perylene Diimide Dimers and Polymers on Bulk Heterojunction Morphology Toward High-Performance Nonfullerene Polymer Solar Cells
Research output: Journal Publications and Reviews (RGC: 21, 22, 62) › 21_Publication in refereed journal › peer-review
Author(s)
Detail(s)
Original language | English |
---|---|
Pages (from-to) | 5326-5332 |
Journal / Publication | Advanced Functional Materials |
Volume | 25 |
Issue number | 33 |
Publication status | Published - 1 Sep 2015 |
Externally published | Yes |
Link(s)
Abstract
In this study, we investigate the influence of molecular geometry of the donor polymers and the perylene diimide dimers (di-PDIs) on the bulk heterojunction (BHJ) morphology in the nonfullerene polymer solar cells (PSCs). The results reveal that the pseudo 2D conjugated poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b′]dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl)] (PTB7-Th) has better miscibility with both bay-linked di-PDI (B-di-PDI) and hydrazine-linked di-PDI (H-di-PDI) compared to its 1D analog, poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7), to facilitate more efficient exciton dissociation in the BHJ films. However, the face-on oriented π-π stacking of PTB7-Th is severely disrupted by the B-di-PDI due to its more flexible structure. On the contrary, the face-on oriented π-π stacking is only slightly disrupted by the H-di-PDI, which has a more rigid structure to provide suitable percolation pathways for charge transport. As a result, a very high power conversion efficiency (PCE) of 6.41% is achieved in the PTB7-Th:H-di-PDI derived device. This study shows that it is critical to pair suitable polymer donor and di-PDI-based acceptor to obtain proper BHJ morphology for achieving high PCE in the nonfullerene PSCs.
Research Area(s)
- 2D conjugated polymers, nonfullerene acceptors, perylene diimide dimers, polymer solar cells
Citation Format(s)
Influence of Molecular Geometry of Perylene Diimide Dimers and Polymers on Bulk Heterojunction Morphology Toward High-Performance Nonfullerene Polymer Solar Cells. / Wu, Chen-Hao; Chueh, Chu-Chen; Xi, Yu-Yin et al.
In: Advanced Functional Materials, Vol. 25, No. 33, 01.09.2015, p. 5326-5332.Research output: Journal Publications and Reviews (RGC: 21, 22, 62) › 21_Publication in refereed journal › peer-review