High Performance All-Polymer Solar Cells by Synergistic Effects of Fine-Tuned Crystallinity and Solvent Annealing.
Artikel i vetenskaplig tidskrift, 2016

Growing interests have been devoted to the design of polymer acceptors as potential replacement for fullerene derivatives for high-performance all polymer solar cells (all-PSCs). One key factor that is limiting the efficiency of all-PSCs is the low fill factor (FF) (normally <0.65), which is strongly correlated with the mobility and film morphology of polymer:polymer blends. In this work, we find a facile method to modulate the crystallinity of the well-known naphthalene diimide (NDI) based polymer N2200, by replacing a certain amount of bithiophene (2T) units in the N2200 backbone by single thiophene (T) units and synthesizing a series of random polymers PNDI-Tx, where x is the percentage of the single T. The acceptor PNDI-T10 is properly miscible with the low band gap donor polymer PTB7-Th, and the nanostructured blend promotes efficient exciton dissociation and charge transport. Solvent annealing (SA) enables higher hole and electron mobilities, and further suppresses the bimolecular recombination. As expected, the PTB7-Th:PNDI-T10 solar cells attain a high PCE of 7.6%, which is a 2-fold increase compared to that of PTB7-Th:N2200 solar cells. The FF of 0.71 reaches the highest value among all-PSCs to date. Our work demonstrates a rational design for fine-tuned crystallinity of polymer acceptors, and reveals the high potential of all-PSCs through structure and morphology engineering of semicrystalline polymer:polymer blends.


Zhaojun Li

Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

Xiaofeng Xu

Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

Wei Zhang

Lunds universitet

Xiangyi Meng

Xi'an Jiaotong University

W. Ma

Xi'an Jiaotong University

Arkady Yartsev

Lunds universitet

Olle Inganäs

Linköpings universitet

Mats Andersson

Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

R. A. J. Janssen

Technische Universiteit Eindhoven

Ergang Wang

Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

Journal of the American Chemical Society

0002-7863 (ISSN) 1520-5126 (eISSN)

Vol. 138 10935-44