초록 |
Non-fullerenesmall molecules (BT-T-IDC and BT-T-tB-IDC) with the A1-π-A2-π-A1 (acceptor1-π-acceptor 2-π-acceptor 1) structure, electron-deficient benzothiadiazole(BT) used as the core (A2), electron-rich thiophene used as the π-bridge (π),and electron-deficient dicyanovinylindandione (IDC) or t-butyl substituted IDCused as end groups (A1), have been applied in organic solar cells. Due tostrong electron-withdrawing property that can lead to deep LUMO energy levels,IDC groups are often used as the acceptor units. According to the decompositiononset temperature (Td) upon 310 °C at 5 wt% loss, the materialsdisplayed good thermal stability. Due to the t-butyl groups on theIDC, BT-T-tB-IDC was more soluble in chloroform and chlorobenzene thanBT-T-IDC. As a result of poor solubility, organic solar cells based on PBDBT-Tand BT-T-IDC demonstrated a low power conversion efficiency (PCE) of 0.06%. Incontrast, the device based on BT-T-tB-IDC obtained a higher PCE of 1.55%. |