Abstract Organic-inorganic hybrid perovskite solar cells (PSCs) have attracted tremendous attention because of their rapid improvement in power conversion efficiency (PCE) over past couple of years. However, electron transporting material, as the necessary part of an integral PSC, is suffering from higher trap state density and mismatched band alignment level with perovskite absorber layer. The strategy of ion doping in electron transporting layer (ETL) is normally applied to enhance the qualities mentioned above. Herein, deoxyribonucleic acid (DNA) with various concentrations is used as dopant into mesoporous-TiO2 (meso-TiO2), which is manufactured by hydrothermal method. It is found that DNA-doping tremendously decreases the trap state density in meso-TiO2, and these traps are major non-radiative recombination centers for carrier in devices, therefore, the carrier recombination rate for PSCs is also decreased along with the reduction of the trap state. Moreover, when 0.2 mg/mL DNA is used as dopant into meso-TiO2, the meso-DNA:TiO2 exhibits optimized band alignment level with perovskite absorber layer, PCE of the cell based on 0.2 mg/mL DNA doped meso-TiO2 is remarkably boosted to 17.59% from 13.25%. These results demonstrate that meso-DNA:TiO2 as electron transporting material can not only improve the performance of PSCs but also exploit the enormous potential of DNA in the field of photovoltaic devices.

中文翻译：

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使用 DNA 掺杂的介孔 TiO2 作为电子传输层增强钙钛矿太阳能电池的性能

摘要 有机-无机杂化钙钛矿太阳能电池（PSC）在过去几年中因其在功率转换效率（PCE）方面的快速提高而引起了极大的关注。然而，作为集成 PSC 的必要部分，电子传输材料正遭受更高的陷阱态密度和与钙钛矿吸收层不匹配的带对准水平。电子传输层 (ETL) 中的离子掺杂策略通常用于提高上述质量。在本文中，将各种浓度的脱氧核糖核酸（DNA）用作掺杂剂进入通过水热法制造的介孔二氧化钛（meso-TiO2）。研究发现，DNA 掺杂极大地降低了 meso-TiO2 中的陷阱态密度，这些陷阱是器件中载流子的主要非辐射复合中心，因此，PSC 的载流子复合率也随着陷阱态的降低而降低。此外，当使用 0.2 mg/mL DNA 作为掺杂剂进入 meso-TiO2 时，meso-DNA:TiO2 表现出与钙钛矿吸收层优化的带排列水平，基于 0.2 mg/mL DNA 掺杂的 meso-TiO2 电池的 PCE 显着从 13.25% 提升至 17.59%。这些结果表明，meso-DNA:TiO2 作为电子传输材料不仅可以提高 PSC 的性能，还可以发挥 DNA 在光伏器件领域的巨大潜力。基于 0.2 mg/mL DNA 掺杂的 meso-TiO2 的细胞 PCE 从 13.25% 显着提高到 17.59%。这些结果表明，meso-DNA:TiO2 作为电子传输材料不仅可以提高 PSC 的性能，还可以发挥 DNA 在光伏器件领域的巨大潜力。基于 0.2 mg/mL DNA 掺杂的 meso-TiO2 的细胞 PCE 从 13.25% 显着提高到 17.59%。这些结果表明，meso-DNA:TiO2 作为电子传输材料不仅可以提高 PSC 的性能，还可以发挥 DNA 在光伏器件领域的巨大潜力。