Planarized Polymer Acceptor Featuring High Electron Mobility for Efficient All-Polymer Solar Cells

Significant progress has been achieved for all-polymer solar cells (APSCs) in the last few years by the use of polymerized small molecular acceptors (PSMAs). Developing high electron mobility polymer acceptors has been considered a feasible solution to further improve the photovoltaic performance of APSCs and fabricate thick film devices, which contributed to roll-to-roll printing techniques. In this work, we designed and synthesized PSV, an A-DA'D-A small molecule acceptor-based PSMA with the vinyl group as a bridged linkage to reduce the steric hindrance between the 1,1-dicyanomethylene-3-indanone (IC) terminal group. In comparison with the C-C bond linked polymer acceptor PS, PSV exhibits an almost planar conjugated framework and well-ordered molecular stacking in the thin film. Moreover, PSV exhibits superior n-type semiconducting properties with high electron mobility of up to 0.54 cm(2)center dot V-1 center dot s(-1), which is the highest value among reported PSMAs. By utilizing PM6 as a polymer donor, PSV-based blend forms a favorable nanomorphology and exhibits high and well-balanced hole/electron mobilities, which is beneficial for exciton separation and charge transport. Consequently, APSCs based on PM6:PSV achieved high power conversion efficiencies of up to 15.73%, with a simultaneously realized high V-oc of 0.923 V, J(sc) of 23.2 mA center dot cm(-2), and FF of 0.734. Such superior features enable PSV with excellent thickness-insensitive properties and over 13% PCE was obtained at 300 nm. To the best of our knowledge, the high PCE of 15.73% with excellent electron mobility of 0.54 cm(2)center dot V-1 center dot s(-1) is the highest values reported for APSCs. These results point to the great significance of developing polymer acceptors with a high electron mobility for boosting the performance of APSCs.

Automated summary

Significant progress has been made in all-polymer solar cells (APSCs) by using polymerized small molecular acceptors (PSMAs). In this study, a high electron mobility polymer acceptor PSV was designed and synthesized, which exhibited excellent performance in APSCs. The results highlight the importance of developing polymer acceptors with high electron mobility for improving the performance of APSCs.