Sheng et al. (2021) report an increase in the power conversion efficiency of a methylammonium lead iodide perovskite solar cell, which they have attributed to the benefits of in situ perovskite-sensitized upconversion by triplet–triplet annihilation in the organic semiconductor rubrene. In the following, we will discuss why in the device structure presented here upconversion inherently cannot be the underlying cause of the observed effects. Rather, the process of upconversion can fundamentally only lead to a reduction of the device efficiency if the same material is used as the active layer in the photovoltaic devices and as the triplet sensitizer. Therefore, the improved photovoltaic performance must have a different root cause. We follow up with an alternative interpretation for the performance increase observed by the authors.

中文翻译：

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W. Sheng、J. Yang、X. Li、G. Liu、Z. Lin、J. Long、S. 评论“高性能钙钛矿太阳能电池的三重态-三重态湮灭上转换使光电流显着增强”。 Xiao, L. Tan 和 Y. Chen，能源环境。科学, 2021, 14, 3532

盛等人。(2021) 报告了甲基铵碘化铅钙钛矿太阳能电池的功率转换效率的提高，他们将其归因于原位的好处通过有机半导体红荧烯中的三重态-三重态湮灭进行钙钛矿敏化上转换。在下文中，我们将讨论为什么这里介绍的器件结构中的上转换本质上不能成为观察到的效应的根本原因。相反，如果相同的材料用作光伏器件中的有源层和三线态敏化剂，则上转换过程基本上只能导致器件效率的降低。因此，提高光伏性能肯定有不同的根本原因。我们对作者观察到的性能提升进行了另一种解释。