Figure (IMAGE) Science China Press Caption (a) Molecular structures of PBDB-TF and BTP-4Cl-X, X represents 8, 12 or 16. (b) statistics of OPV cell under different preparation conditions. Credit �Science China Press Usage Restrictions Use with credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.