Hybrid perovskites represent a potential paradigm shift for the creation of low-cost solar cells. Current power conversion efficiencies (PCEs) exceed 22%. However, despite this, record PCEs are still far from their theoretical Shockley–Queisser limit of 31%. To increase these PCE values, there is a pressing need to understand, quantify and microscopically model charge recombination processes in full working devices. Here, we present a complete microscopic account of charge recombination processes in high efficiency (18–19% PCE) hybrid perovskite (mixed cation and methylammonium lead iodide) solar cells. We employ diffraction-limited optical measurements along with relevant kinetic modeling to establish, for the first time, local photoluminescence quantum yields, trap densities, trapping efficiencies, charge extraction efficiencies, quasi-Fermi-level splitting, and effective PCE estimates. Correlations between these spatially resolved parameters, in turn, allow us to conclude that intrinsic electron traps in the perovskite active layers limit the performance of these state-of-the-art hybrid perovskite solar cells.

中文翻译：

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高效，平面混合钙钛矿型太阳能电池性能瓶颈的定量和空间分辨分析†

混合钙钛矿代表了低成本太阳能电池制造的潜在范例转变。当前的功率转换效率（PCE）超过22％。但是，尽管如此，创纪录的PCE仍远没有达到其理论的Shockley-Queisser极限（31％）。为了增加这些PCE值，迫切需要了解，量化和微观模型化完整工作设备中的电荷重组过程。在这里，我们介绍了高效（18-19％PCE）混合钙钛矿（混合阳离子和甲基铵碘化铅）太阳能电池中电荷复合过程的完整微观描述。我们采用衍射极限光学测量方法以及相关的动力学模型，首次建立了局部光致发光量子产率，陷阱密度，陷阱效率，电荷提取效率，准费米级分裂和有效的PCE估计。这些空间分辨参数之间的相关性反过来使我们得出结论，钙钛矿活性层中的固有电子陷阱限制了这些先进的混合钙钛矿太阳能电池的性能。