Selecting a Donor Polymer for Realizing Favorable Morphology in Efficient Non‐fullerene Acceptor‐based Solar Cells

Abstract

A highly efficient non‐fullerene small molecule‐based polymer solar cell (n‐PSC) is realized by employing PBDTBDD as donor polymer and singly linked perylene bisimide (SDIPBI) as acceptor with PCE up to 4.4%, which is one of the outstanding values among n‐PSCs so far. In particular, high Voc of 0.87 V and FF over 60% are achieved for PBDTBDD: SDIPBI based PSCs.

Non-Fullerene-Acceptor-Based Bulk-Heterojunction Organic Solar Cells with Efficiency over 7%

“…[17][18][19][20][21][22] In spite of these favorable properties, PBI-based organic solar cells usually show low performance due to the formation of large aggregates in the active layer where strong self-trapping of excitons occurs and thus severely limits the exciton diffusion/separation process. [23][24][25] Accordingly, to avoid large crystalline aggregate domains, twisted PBI compounds are designed, 14,15,[26][27][28][29][30][31][32][33][34][35][36][37][38][39] mainly by the means of PBI dimers linked at the imide positions or bay positions (1, 6, 7, 12-positions) either by direct attachment or through functional groups. Such kinds of PBI dimers yield BHJ organic solar cells with high PCEs over 6%.…”

The Effect of Aromatic Diimide Side Groups on the π-Conjugated Polymer Properties

“…According to literature data, there are no efficient solar cells with simple, low molecular PDI or NDI units. However, modification of PDI units by incorporation of additional aromatic side groups [14], combining of few PDI units [15][16][17], or the incorporation of side atoms stiffening the structure [18,19] can be an effective way to significantly improve the performance of organic solar cells up to 8.4%. There are examples of polymers with PDI in the main polymer chain [10,20].…”

Loss mechanisms in organic solar cells based on perylene diimide acceptors studied by time-resolved photoluminescence

“…12 Furthermore, smaller domain sizes have been successfully realized with twisted dimers. [13][14][15][16][17][18] In this context also the rational selection of donor polymers and fine-tuning their properties have proven successful. 15,16 The steady progress in the field of PDI-based OPV materials recently yielded a PCE exceeding 7 % for a twisted dimer.…”

“…[13][14][15][16][17][18] In this context also the rational selection of donor polymers and fine-tuning their properties have proven successful. 15,16 The steady progress in the field of PDI-based OPV materials recently yielded a PCE exceeding 7 % for a twisted dimer. 18 This motivates further research, not only in terms of exploring and optimizing novel material systems, but also a detailed understanding of the underlying mechanisms of charge generation and the accompanying loss channels is desirable.…”