Abstract：
One of the main barriers to making efficient Photosystem I-based biohybrid solar cells is the need for an electrochemical pathway to facilitate electron transfer between the P700 reaction center of Photosystem I and an electrode. To this end, nature provides inspiration in the form of cytochrome c6, a natural electron donor to the P700 site. Its natural ability to access the P700 binding pocket and reduce the reaction center can be mimicked by employing cytochrome c, which has a similar protein structure and redox chemistry while also being compatible with a variety of electrode surfaces. Previous research has incorporated cytochrome c to improve the photocurrent generation of Photosystem I using time consuming and/or specialized electrode preparation. While those methods lead to high protein areal density, in this work we use the quick and facile vacuum-assisted drop-casting technique to construct a Photosystem I/cytochrome c photoactive composite film with micron-scale thickness. We demonstrate that this simple fabrication technique can result in high cytochrome c loading and improvement in cathodic photocurrent over a drop-casted Photosystem I film without cytochrome c. In addition, we analyze the behavior of the cytochrome c/Photosystem I system at varying applied potentials to show that the improvement in performance can be attributed to enhancement of the electron transfer rate to P700 sites and therefore the PSI turnover rate within the composite film.
摘要：
制造有效的基于光系统I的生物混合太阳能电池的主要障碍之一是需要电化学途径以促进光系统I的P700反应中心与电极之间的电子转移。为此,自然界以细胞色素c6的形式提供灵感，细胞色素c6是P700位点的天然电子供体。通过采用细胞色素c可以模拟其进入P700结合口袋和减少反应中心的自然能力，它具有相似的蛋白质结构和氧化还原化学，同时还与各种电极表面兼容。先前的研究已经结合了细胞色素c以使用耗时和/或专门的电极制备来改善光系统I的光电流产生。虽然这些方法导致高蛋白质面密度，在这项工作中，我们使用快速简便的真空辅助滴注技术来构建具有微米级厚度的光系统I/细胞色素c光活性复合膜。Wedemonedthatthissimplefabricationtechnologycanresultinhighcytellchromecloadingandimprovementincathorodinephoturentoveradrop-castedPhotosystemIfilmwithoutcytellchromec.Inaddition,我们分析了细胞色素c/光系统I系统在不同施加电势下的行为，以表明性能的改善可归因于电子转移到P700位点的速率的增强，因此复合膜内的PSI转换率。
