Y-serious acceptors and the multi-components strategy, the power conversion efficiencies (PCEs) of the single-junction OPVs have already reached 19%, [19,20] with the best fill factors (FFs) exceeding 80%. [21,22] However, the trade-off between the open-circuit voltage (V oc ) and the short-circuit current density (J sc ) still remains as a challenge to handle with in OPV devices. [23][24][25][26][27] Therefore, the synergistic improvement of V oc and J sc will be attractive for marching the efficiencies further for OPVs. [28][29][30] The charge transfer (CT) state cannot only affect the energy loss (E loss ) but also the generation efficiency of photo-induced carriers. [26] Narrowing the offset (ΔE LE-CT ) between the energy level of the CT state (E CT ) and the lowest excited state (E LE ) may reduce the probability of excitons quenching back to the ground state, which helps in mitigating E loss for a higher V oc . However, the diminished driving force is not in favor of exciton dissociation for a higher J sc , and vice versa. [29] The properties of CT states at the donor-acceptor (D-A) interfaces are supposed to be affected by the morphology Balancing and improving the open-circuit voltage (V oc ) and short-circuit current density (J sc ) synergistically has always been the critical point for organic photovoltaics (OPVs) to achieve high efficiencies. Here, this work adopts a ternary strategy to regulate the trade-off between V oc and J sc by combining the symmetric-asymmetric non-fullerene acceptors that differ at terminals and alkyl side chains to build the ternary OPV (TOPV). It is noticed that the reduced energy disorder and the enhanced luminescence efficiency of TOPV enable a mitigated energy loss and a higher V oc . Meanwhile, the third component, which is distributed at the host donor-acceptor interface, acts as the charge transport channel. The prolonged exciton lifetime, the boosted charge mobility, and the depressed charge recombination promote the TOPV to obtain an improved J sc . Finally, with synergistically improved V oc and J sc , the TOPV delivers an optimal efficiency of 19.26% (certified as 19.12%), representing one of the highest values reported so far.

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