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A new molecule with dithieno[3,2-b:2’,3’-d]pyrrole (DTP) as central moiety and two terminal diketopyrrolopyrrole (DPP) units named DPP-DTPC8 has been designed and synthesized. The push–pull molecule exhibits excellent thermal stability, strong absorption in visible region, and matched energy levels. Devices fabricated from DTPC8:PC${}_{71}$BM blend films exhibit the maximum power conversion efficiency of 2.75%, with Voc of 0.63 V, Jsc of 9.94 mA$\cdot$ cm${}^{-2}$, and FF of 43.8%. The active layers undergo thermal annealing or solvent vapor annealing treatments, exhibiting inconspicuous influence on the aggregation of the molecule. This study demonstrates that the new molecule DPP-DTPC8 tailored with DTP and DPP units could affect the thermal stability, absorption, energy levels and morphology that manage the photovoltaic performances.

A novel non-fullerene small molecule acceptor named DPPMDPC6 with diketopyrrolopyrrole (DPP) as central moiety and methyl-dioxocyano-pyridine (MDP) units as two branches has been designed and synthesized. Benefitted from the quinoidal MDP segment, the molecule exhibits effective electron delocalization extending to the near infrared (NIR) region absorption with narrow bandgap of 1.42eV. The acceptor also displayed intrinsic properties with good thermal stability, and matched energy levels with various donor materials especially for the commercial polymer PTB7. Under optimized condition, the devices fabricated by forming PTB7:DPPMDPC6 blend films yield a moderate PCE of 5.80% with a $V_{\mathrm{\text{oc}}}$ of 0.84V, a $J_{\mathrm{\text{sc}}}$ of 12.94mA$\cdot$cm${}^{-2}$, and an FF of 53.4%. This preliminary study demonstrates that the new acceptor tailored with quinoidal MDP units could lead to enhancement on the low energy absorption band that is favorable for the photovoltaic performances.