Semi-transparent perovskite solar cells are highly attractive for a wide range of applications, such as bifacial and tandem solar cells; however, the power conversion efficiency of semi-transparent devices still lags behind due to missing suitable transparent rear electrode or deposition process. Here we report a low-temperature process for efficient semi-transparent planar perovskite solar cells. A hybrid thermal evaporation-spin coating technique is developed to allow the introduction of PCBM in regular device configuration, which facilitates the growth of high-quality absorber, resulting in hysteresis-free devices. We employ high-mobility hydrogenated indium oxide as transparent rear electrode by room-temperature radio-frequency magnetron sputtering, yielding a semi-transparent solar cell with steady-state efficiency of 14.2% along with 72% average transmittance in the near-infrared region. With such semi-transparent devices, we show a substantial power enhancement when operating as bifacial solar cell, and in combination with low-bandgap copper indium gallium diselenide we further demonstrate 20.5% efficiency in four-terminal tandem configuration.

中文翻译：

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适用于双面和串联应用的经过低温处理的高效半透明平面钙钛矿型太阳能电池。

半透明钙钛矿太阳能电池对双面和串联太阳能电池等广泛应用具有高度吸引力。然而，由于缺少合适的透明后电极或沉积工艺，半透明器件的功率转换效率仍然落后。在这里，我们报告了一种有效的半透明平面钙钛矿太阳能电池的低温工艺。开发了一种混合式热蒸发自旋涂层技术，可将PCBM引入常规的器件配置中，从而促进了高质量吸收体的生长，从而实现了无滞后的器件。我们通过室温射频磁控溅射采用高迁移率的氢化氧化铟作为透明后电极，从而生产出稳态效率为14的半透明太阳能电池。2％以及近红外区域的平均透射率达到72％。使用这种半透明器件，当作为双面太阳能电池工作时，我们显示出了显着的功率增强，并且与低带隙铜铟镓二硒化物组合使用时，我们进一步证明了四端子串联配置的效率为20.5％。