Side chain engineering of n-type conjugated polymer enhances photocurrent and efficiency of all-polymer solar cells

Abstract

Side chain engineering of an n-type polymer provides a means of maintaining solubility while increasing crystallinity and electron mobility, leading to enhanced photocurrent. Bulk heterojunction solar cells composed of a side chain engineered copolymer (PNDIS-30BO) as acceptor and PSEHTT as donor give 10.4 mA cm(-2) photocurrent and 4.4% efficiency.

Development and Structure/Property Relationship of New Electron Accepting Polymers Based on Thieno[2′,3′:4,5]pyrido[2,3-g]thieno[3,2-c]quinoline-4,10-dione for All-Polymer Solar Cells

“…All-polymer solar cells showing PCE as high as 6.7% have been reported. [17][18][19][20][21][22][23][24][25] However, it was realized that energy level match alone is not enough to achieve high efficiency in all-polymer solar cells. Previously, we reported alternating electron accepting polymers with the following monomer-comonomer combination: a) Weak donating monomer-strong accepting monomer (WD-SA), b) Weak accepting monomer-strong accepting monomer (WA-SA), c) Strong donating monomerstrong accepting monomer (SD-SA).…”

Photoactive Compounds Based on the Thiazolo[5,4‐d]thiazole Core and Their Application in Organic and Hybrid Photovoltaics

“…In their studies on alternative acceptors, Jenekhe and co-workers extensively explored the use of copolymer PSEHTT (Figure 4) as the donor in combination with various different naphthalene diimide derivatives, both polymers [93][94][95][96][97] and small-molecule compounds. [98][99][100] The best PCE of 6.18 % (with a high V oc of 0.92 V) was obtained with dimeric acceptor DBFI-DMT: [100] the authors explain such an excellent performance in terms of the relatively high-lying LUMO of the acceptor coupled with its particular, twisted 3D conformation, which had a positive influence on the bulk charge-transport properties of the photovoltaic devices.…”

Novel Approaches in the Design of Donor-Acceptor Oligomeric and Polymeric Materials for Photovoltaic Applications: D/A Blend versus Self-assembly of D/A by Covalent or Non-Covalent Interaction

“…Average charge carrier mobility of the donor-acceptor blend measured using both OFET and SCLC devices showed balanced electron and hole transport for NDI-14a: PSEHTT blend as the active layer. Jenekhe's group achieved solar cells with PCE 4.4% and short circuit current density of 10.4 mA/cm 2 using naphthalenediimide-selenophene copolymer (PNDIS-x-BO; structure NDI-16) as the acceptor and PSEHTT as donor in an inverted solar cell device [33]. Compared to the PCE value of 2.62% for the combination PSEHTT/NDI-14b, a high PCE of 3.61% was obtained for the combination PSEHTT/NDI-16 (random incorporation of NDI with butyl octyl (BO) side chain; x=30%) demonstrating the influence of side chain engineering of the alkyl substituent.…”

“…Even though the self-assembly approach received such wide publicity, when it came to actual device performance it fell way short of expectations. On the other hand, the D-A blend approach dominated the area with the best power conversion efficiencies (PCEs) reported in organic solar cells [31][32][33]. Poor morphology has sometimes been cited as the culprit that prevented the self-assembly approach from attaining its full potential as a simple and easy approach towards large scale active area device fabrication.…”