Biomaterials Interfaces for Photoactive Proteins

非技术：授予范德比尔特和田纳西州立大学的这一奖项将探索将蛋白质整合到设备中的根本性进展，以加快生物混合太阳能电池的开发，从而产生负担得起的可再生能源。 一个由两名化学家和一名化学工程师组成的团队将在这个项目中合作开发自然启发的太阳能电池，该电池使用来自绿色植物的蛋白质作为光敏元件。 蛋白质复合物光系统I（PSI）和光系统II（PSII）驱动植物的光合作用，是高效的太阳能转换器。该团队的成员具有将PSI和PSII薄膜与电极表面集成的经验，以设计和构建光电化学电池，其光电流在过去五年中提高了近106倍，并且现在处于许多成熟技术的数量级之内。 该研究项目将解决关键的基本生物材料问题，以大大提高基于光系统的太阳能电池的性能。该项目的研究团队将建立在他们在范德比尔特和田纳西州立大学（HBCU）将研究与教育相结合的良好记录的基础上，通过研究经验和跨学科课程，促进工程和化学研究生和本科生的跨学科教育。 通过菲斯克和田纳西州HBCUs将来自代表性不足群体的学生纳入既定的外展计划，并与范德比尔特暑期学院和范德比尔特学生科学志愿者的K-12课堂外展相结合。在这个项目中，来自范德比尔特和田纳西州立大学的团队将开发一种仿生方法，在电极表面上定位PSI，探索将这些蛋白质与导电材料连接的新方法，以促进电子流到蛋白质/从蛋白质，并促进能带能量对准，以实现生物混合太阳能转换的另一个量子飞跃。 首先，在释放修饰的蛋白质用于定向组装到表面上之前，通过用表面活性配体选择性地修饰类囊体膜内PSI的暴露基质面，将极大地增强电极表面处的PSI取向。 在不依赖昂贵且缓慢的替代方法的情况下实现这些生物分子光电二极管的均匀取向将极大地提高生物杂交性能。 第二，PSI膜内的导电性将通过将还原的氧化石墨烯、氧化还原聚合物和半导体纳米颗粒连接到活性PSI位点来促进。 这些取向的和更导电的PSI膜将与两种类型的电极系统在湿和固态系统中界面连接。 基于该小组最近的成功，PSI薄膜将与具有适当能级的半导体连接，以引导电子单向流过电路。 此外，将设计、制造和优化一种全碳基太阳能电池，其中PSI膜夹在相对掺杂的原子级薄石墨烯片之间，以产生对入射光仅有轻微阻抗的“堆叠”结构。 这些进展也将被应用到PSII到基板电极的接口和光电化学。 PI将创建外展组件和套件，用于在初中和高中环境中构建和演示这些设备。

Non-Technical:This award to Vanderbilt and Tennessee State Universities will explore fundamental advances in the integration of proteins into devices to speed the development of biohybrid solar cells for the generation of affordable, renewable power. A team of two chemists, and a chemical engineer will collaborate in this project to develop nature-inspired solar cells that use proteins from green plants as the photo-active elements. The protein complexes Photosystem I (PSI) and Photosystem II (PSII) drive photosynthesis in plants and are highly efficient solar converters. Members of this team have experience in integrating PSI and PSII films with electrode surfaces to design and construct photoelectrochemical cells with photocurrents that have improved by a factor of nearly 106 over the past five years and are now within an order of magnitude of many mature technologies. This research project will address key fundamental biomaterials issues to greatly enhance the performance of photosystem-based solar cells. The research team for this project will build on their strong track record of integrating research with education at Vanderbilt and Tennessee State University, an HBCU, by promoting the interdisciplinary education of graduate and undergraduate researchers in engineering and chemistry through research experiences and interdisciplinary coursework. An established outreach program to include students from under-represented groups through Fisk and Tennessee State HBCUs is combined with K-12 classroom outreach in the Vanderbilt Summer Academy and Vanderbilt Student Volunteers for Science.Technical:In this project, the team from Vanderbilt and Tennessee State will develop a biomimetic approach to orient PSI on electrode surfaces, explore new ways of interfacing these proteins with conductive materials to facilitate electron flow to/from the proteins, and promote band energy alignment with the goal to achieve another quantum leap in biohybrid solar energy conversion. First, PSI orientation at electrode surfaces will be greatly enhanced by selectively modifying the exposed stromal face of PSI within the thylakoid membrane with surface-active ligands before releasing the modified protein for directed assembly onto surfaces. Achieving uniform orientations of these biomolecular photodiodes without the reliance on expensive and slow alternative methods would greatly advance biohybrid performance. Second, the conductivity within PSI films will be promoted by wiring reduced graphene oxide, redox polymers, and semiconductor nanoparticles to the active PSI sites. These oriented and more conductive PSI films will be interfaced with two types of electrode systems in both wet and solid-state systems. Building from the group's recent success, PSI films will be interfaced with semiconductors with appropriate energy levels to guide electron flow unidirectionally through the circuit. In addition, an all-carbon-based solar cell in which PSI films are sandwiched between oppositely doped, atomically thin graphene sheets to yield "stacked" architectures with only slight impedance of incoming light will be designed, fabricated, and optimized. These advances will also be applied to the interfacing and photoelectrochemistry of PSII onto substrate electrodes. The PIs will create outreach components and kits for building and demonstrating these devices in the middle school and high school settings.