Suppressing energy/voltage loss and realizing efficient charge transfer at small frontier molecular orbital offsets between donor and acceptor is viable to simultaneously improve open-circuit voltage (Voc) and short-circuit current (Jsc), and thus power conversion efficiency (PCE) of organic solar cells (OSCs). Here, two A-DA’D-A type acceptors, PEH-F and TEH-F, are designed and synthesized with different conjugated outer side chains, to pursue high-efficiency and cost-effective OSCs for industrialization. In comparison with TEH-F (thienyl outer side chain), PEH-F with phenyl outer side chains delivers up-shifted frontier energy levels, wider optical bandgap, and higher absorption coefficient. By adopting low-cost polymer PTQ11 as donor, the PEH-F-based device realizes low energy loss of 0.511 eV with suppressed non-radiative loss of only 0.182 eV, and exhibits efficient exciton dissociation and hole transfer even at an extremely small highest occupied molecular orbital offset of 0.06 eV. Eventually, the PTQ11:PEH-F-based binary device demonstrates a superior PCE of 19.73 % with high Voc and Jsc simultaneously, which is the highest PCE to date for OSCs based on low-cost polymer donors. More importantly, this device shows small efficiency-cost gap for industrialization with the estimated minimum sustainable price (MSP) of 0.35 $ Wp-1, which is dramatically lower than other reported high-performance OSCs.

中文翻译：

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抑制非辐射损耗和在小、最高占据的分子轨道偏移处实现高效的空穴转移，使二元有机太阳能电池的效率达到 19.73%，效率成本差距很小


抑制能量/电压损失并在供体和受体之间的小前沿分子轨道偏移处实现高效的电荷转移，可以同时提高有机太阳能电池 （OSC） 的开路电压 （Voc） 和短路电流 （Jsc），从而提高功率转换效率 （PCE）。在这里，PEH-F 和 TEH-F 两个 A-DA'D-A 型受体被设计并合成具有不同共轭外侧链，以追求用于工业化的高效率和成本效益的 OSC。与 TEH-F（噻吩基外侧链）相比，具有苯基外侧链的 PEH-F 可提供上移的前沿能级、更宽的光学带隙和更高的吸收系数。通过采用低成本聚合物 PTQ11 作为供体，基于 PEH-F 的器件实现了 0.511 eV 的低能量损失，抑制的非辐射损耗仅为 0.182 eV，即使在 0.06 eV 的极小最高占据分子轨道偏移下也表现出高效的激子解离和空穴转移。最终，基于 PTQ11：PEH-F 的二元器件在高 Voc 和 Jsc 同时具有高 Voc 和 Jsc 的情况下表现出 19.73% 的优异 PCE，这是迄今为止基于低成本聚合物供体的 OSC 的最高 PCE。更重要的是，该设备在工业化方面显示出较小的效率-成本差距，估计最低可持续价格 （MSP） 为 0.35 美元 Wp-1，大大低于其他报道的高性能 OSC。