A Versatile and Low‐Cost Polymer Donor Based on 4‐Chlorothiazole for Highly Efficient Polymer Solar Cells

Abstract

Benefiting from the emergence of narrow‐band‐gap small‐molecule acceptors (SMAs), especially “Y” series, the power conversion efficiency (PCE) of polymer solar cells (PSCs) is rapidly improved. However, polymer donors with high efficiency, easy synthesis, and good universality are relatively scarce except PBDB‐TF and D18. Herein, two polymer donors are designed and synthesized based on 4‐chlorothiazole derivatives with simple structures, namely PTz3Cl and PBTTz3Cl. The OSCs based on PBTTz3Cl with slightly weaker intermolecular forces in comparison to PTz3Cl exhibits a decent PCE of 18.38% in blending with SMA L8‐BO, owing to its strong donor/acceptor interaction with L8‐BO, which shapes suitable phase separation morphology. Further research finds that PBTTz3Cl can exhibit excellent photovoltaic performances with various SMA materials, highlighting its universality. Based on this, ternary PSCs are designed where BTP‐eC9 is introduced as a guest into the PBTTz3Cl:L8‐BO host system. Thanks to further optimal blend morphology and more balanced charge transport, the PCE is improved up to 19.12%, which is among the highest values for PSCs. This work provides a new design of low‐cost electron‐deficient units for constructing highly versatile, high‐performance polymer donors.

High-speed printing of a bulk-heterojunction architecture in organic solar cells films

“…Organic solar cells (OSCs) based on a bulk-heterojunction (BHJ) architecture, consisting of mixed donor (D) and acceptor (A) materials, have received much attention in recent decades, owing to their advantages of intrinsic flexibility, low-cost, solution processability and semitransparency. 1–6 So far, the non-fullerene acceptor (NFA)-based OSCs deliver promising power conversion efficiencies (PCEs) with over 19%, 7–11 drawing on the rapid improvement of materials design, morphology control, interface, and device engineering. 12–17 Notably, although many aspects, including internal factors, external conditions and synergistic stresses, etc.…”

“…Organic solar cells (OSCs) based on a bulk-heterojunction (BHJ) architecture, consisting of mixed donor (D) and acceptor (A) materials, have received much attention in recent decades, owing to their advantages of intrinsic flexibility, low-cost, solution processability and semitransparency. [1][2][3][4][5][6] So far, the non-fullerene acceptor (NFA)-based OSCs deliver promising power conversion efficiencies (PCEs) with over 19%, [7][8][9][10][11] drawing on the rapid improvement of materials design, morphology control, interface, and device engineering. [12][13][14][15][16][17] Notably, although many aspects, including internal factors, external conditions and synergistic stresses, etc., [18][19][20] influence the BHJ morphology degradation behaviors of OSCs, 21 recent improvements in operational and thermal stability issues have been greatly facilitated by various approaches, such as solvent and solid additives, non-fused NFAs, cross-linkable polymers and so on.…”

“…[22][23][24][25][26] Of particular note is that many NFA-based active layer systems with high device performance and low synthesis cost (or low synthetic complexity) are also widely developed. 6,10,21,27,28 Based on these visible developments in the OSC filed in terms of device efficiency, operation stability, and materials cost, it can be seen that scalable manufacturing issues (including, eco-friendly processability of function layers, scaling lag of device efficiency, high-speed coating capability, and encapsulation techniques), 13,29,30 which also determine the commercialization of OSCs, are becoming more prominent.…”

Recent Advances in Organic Photovoltaic Materials Based on Thiazole‐Containing Heterocycles

“…And the OSCs that utilized Tz‐based photovoltaic materials have shown high open‐circuit voltage ( V OC ) with E loss . Until the present moment, Tz‐based photovoltaic materials as donors or acceptors have been widely reported and yielded high performance, such as PBTTz3Cl, [ 18 ] HD‐1. [ 19 ] In 2012, Zhan et al reviewed the developments in Tz‐based small molecules and polymers for applications in OSCs.…”

Layer‐by‐Layer‐Processed Ternary All‐Polymer Organic Solar Cells with 17.74% Efficiency Enabled by Introducing a Designed Narrow‐Bandgap Guest Polymer Acceptor

“…[6][7][8][9][10][11] Impressively, the PCEs of related OSCs based on nonfused ring electron acceptors and/or low-cost polymer donors also continue to breakthrough. [12][13][14] Despite this, state of the art organic photovoltaic systems as mentioned above still have some inescapable challenges, special in terms of stability issues, including thermal stability, mechanical robustness, flexibility, etc. [4,[15][16][17] which limit the viability of OSCs for practical commercial applications.…”