Biomaterials Interfaces for Photoactive Proteins

非技术：该奖项授予范德比尔特大学和田纳西州立大学，将探索将蛋白质集成到设备中的根本进展，以加快生物混合太阳能电池的开发，以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受自然启发的太阳能电池，这种电池使用来自绿色植物的蛋白质作为光活性元素。蛋白质复合体光系统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。该团队的成员在将PSI和PSII薄膜与电极表面相结合以设计和构建具有光电电流的光电化学电池方面拥有经验，在过去五年中，光电化学电池的性能提高了近106倍，目前处于许多成熟技术的数量级之内。这项研究项目将解决关键的基础生物材料问题，以极大地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在范德比尔特大学和田纳西州立大学(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工作，促进工程和化学方面的研究生和本科生研究人员的跨学科教育。范德比尔特夏季学院和范德比尔特科学学院的K-12课堂推广与范德比尔特大学和田纳西州立大学学生志愿者的K-12课堂推广相结合，建立了一个扩展计划，包括来自FISK和田纳西州立大学的代表不足群体的学生。技术：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，在电极表面定位PSI，探索将这些蛋白质与导电材料接口的新方法，以促进蛋白质之间的电子流动，并促进能带能量对齐，目标是实现生物混合太阳能转换的又一次巨大飞跃。首先，通过在类囊体膜内PSI暴露的基质表面选择性地修饰表面活性配体，然后将修饰后的蛋白质释放到电极表面进行定向组装，PSI在电极表面的取向将大大增强。在不依赖昂贵和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。其次，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的PSI位上，PSI膜的导电性将得到提高。这些定向和更具导电性的PSI薄膜将在湿和固态系统中与两种类型的电极系统连接。在该集团最近成功的基础上，PSI薄膜将与具有适当能级的半导体接口，以引导电子在电路中单向流动。此外，还将设计、制造和优化一种全碳基太阳能电池，在这种电池中，PSI薄膜被夹在相反掺杂的原子薄石墨烯之间，以产生只有轻微入射光阻抗的“堆叠”结构。这些进展也将应用于PSII在衬底电极上的界面和光电化学。PI将创建扩展组件和套件，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.