S•••Cl intramolecular interaction: An efficient strategy to improve power conversion efficiency of organic solar cells

Noncovalent conformational locks (NCLs) including S center dot center dot center dot N, Se center dot center dot center dot O, and S center dot center dot center dot O etc. Have been an effective strategy to improve the planarity and rigidity, and charge transport mobility of organic/polymeric semiconductors. Herein, by replacing methyl group (ITMIC) with chlorine (ITCIC) in the pi-bridge, the planarity and rigidity of the pi-conjugated skeleton was enhanced by introduction of S center dot center dot center dot Cl NCLs, thus the charge transport mobility was improved accordingly. As a result, PM6:ITCIC based organic solar cells showed impressive PCE of 11.34%, much higher than that based on PM6:ITMIC. This contribution demonstrated a novel kind NCLs (S center dot center dot center dot Cl) for improving the performance of organic solar cells.