Fabricating organic solar cells (OSCs) with a tandem structure has been considered an effective method to overcome the limited light absorption spectra of organic photovoltaic materials. Currently, the most efficient tandem OSCs are fabricated by adopting fullerene derivatives as acceptors. In this work, we designed a new non-fullerene acceptor with an optical band gap (E_g^opt) of 1.68 eV for the front subcells and optimized the phase-separation morphology of a fullerene-free active layer with an E_g^opt of 1.36 eV to fabricate the rear subcell. The two subcells show a low energy loss and high external quantum efficiency, and their photoresponse spectra are complementary. In addition, an interconnection layer (ICL) composed of ZnO and a pH-neutral self-doped conductive polymer, PCP-Na, with high light transmittance in the near-IR range was developed. From the highly optimized subcells and ICL, solution-processed fullerene-free tandem OSCs with an average power conversion efficiency (PCE) greater than 13% were obtained.

中文翻译：

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精调的光敏层和互连层，可在不含富勒烯的串联有机太阳能电池中实现超过13％的效率

具有串联结构的有机太阳能电池（OSC）的制造已被认为是克服有机光伏材料有限的光吸收光谱的有效方法。当前，最有效的串联OSC是通过采用富勒烯衍生物作为受体来制造的。在这项工作中，我们为前子电池设计了一个新的非富勒烯受体，其光学带隙（E _g ^opt）为1.68 eV，并优化了带有E _g ^opt的无富勒烯活性层的相分离形态1.36 eV的电压来制造后部子电池。这两个子电池显示出低能量损失和高外部量子效率，并且它们的光响应光谱是互补的。另外，开发了由ZnO和pH中性自掺杂导电聚合物PCP-Na组成的互连层（ICL），该互连层在近IR范围内具有高透光率。从高度优化的子电池和ICL中，获得了平均功率转换效率（PCE）大于13％的溶液处理的无富勒烯串联OSC。