Chlorophyll (Chl) derivatives have recently been proposed as photoactive materials in next-generation bio-inspired solar cells, because of their natural abundance, environmental friendliness, excellent photoelectric performance, and biodegradability. However, the intrinsic excitation dynamics of Chl derivatives remain unclear. Here, we show sub-nanosecond pump–probe time-resolved absorption spectroscopy of Chl derivatives both in solution and solid film states. We observe the formation of triplet-excited states of Chl derivatives both in deoxygenated solutions and in film samples by adding all-trans-β-carotene as a triplet scavenger. In addition, radical species of the Chl derivatives in solution were identified by adding hydroquinone as a cation radical scavenger and/or anion radical donor. These radical species (either cations or anions) can become carriers in Chl-derivative-based solar cells. Remarkably, the introduction of hydroquinone to the film samples enhanced the carrier lifetimes and the power conversion efficiency of Chl-based solar cells by 20% (from pristine 1.29% to 1.55%). This enhancement is due to a charge recombination process of Chl-A⁺/Chl-D^–, which is based on the natural Z-scheme process of photosynthesis.

叶绿素 (Chl) 衍生物最近被提议作为下一代仿生太阳能电池中的光活性材料，因为它们天然丰富、环境友好、优异的光电性能和生物降解性。然而，叶绿素衍生物的内在激发动力学仍不清楚。在这里，我们展示了叶绿素衍生物在溶液和固体薄膜状态下的亚纳秒泵浦-探针时间分辨吸收光谱。我们通过添加全反式-β-胡萝卜素作为三重态清除剂，在脱氧溶液和薄膜样品中观察到叶绿素衍生物三重激发态的形成。此外，通过添加氢醌作为阳离子自由基清除剂和/或阴离子自由基供体，鉴定了溶液中 Chl 衍生物的自由基种类。这些自由基物种（阳离子或阴离子）可以成为基于叶绿素衍生物的太阳能电池中的载体。值得注意的是，将对苯二酚引入薄膜样品后，载流子寿命和叶绿素基太阳能电池的功率转换效率提高了 20%（从原始的 1.29% 提高到 1.55%）。这种增强是由于 Chl-A 的电荷重组过程⁺ /Chl-D ^–，它基于光合作用的自然 Z 型过程。