Manufacturing of Hydrocarbon Fuels from Sunlight, Carbon Dioxide and Water with Metal Nanostructures: Mechanistic Investigations to Improve Performance

该奖项的目的是研究最近发现的一种高效人工光合作用过程的基本机制，该过程利用钴或铁纳米结构在简单的反应室中利用太阳能直接将二氧化碳和水转化为碳氢燃料。该项目将解决在初步研究中遇到的基本问题：纳米结构金属表面的光合作用机制是什么？飞秒激光纳/微加工表面的形貌和三相(气/液/固)界面的存在如何影响光合作用速率？这些问题的答案将通过研究人工光合作用过程的关键方面来获得，例如：(A)用于捕光的表面等离子体光吸收；(B)光解离和碳氢化合物合成的速率；以及(C)长期使用的金属纳米结构的寿命/耐久性。基于通过这项研究获得的知识，可以找到一种成本效益高的大规模光合作用制造工艺，以满足全球能源需求。拟议的研究结果将使科学家能够克服人工光合作用技术大规模应用的关键现有障碍。高效的人工光合作用将减少全球能源问题，减少美国对外国进口和化石燃料的依赖，并解决大气中二氧化碳浓度高等环境问题。有关金属纳米结构性质的信息也将对纳米结构和光物理/化学/生物学广泛应用的其他领域有价值，如医学、环境、化学生产、军事和安全。该方法也有可能适用于对农业影响较大的日光化肥生产。拟议的工作将有助于通过以研究为基础的教育培养多学科的科学家和工程师。

The objective of this award is to study the fundamental mechanisms of a recently discovered, highly efficient artificial photosynthesis process utilizing cobalt or iron nanostructures to directly convert carbon dioxide and water into hydrocarbon fuels with solar energy in a simple reaction chamber. The project will address fundamental questions encountered in preliminary research: What is the mechanism of photosynthesis on nanostructured metal surfaces? How does the morphology of the femtosecond laser nano/micro-machined surface and the presence of a three-phase (gas/liquid/solid) interface affect the photosynthesis rate? Answers to these questions will be obtained by studying key aspects of the artificial photosynthesis process such as (a) the surface plasmon optical absorption for light harvesting; (b) the rates of photodissociation and hydrocarbon synthesis; and (c) the lifetime/durability of the metal nanostructures for long-term use. Based on the knowledge acquired through this research, a cost-effective photosynthesis manufacturing process on a large scale can be found to meet global energy needs.Results from the proposed research will enable scientists to overcome key existing barriers to large-scale applications of the artificial photosynthesis technology. Efficient artificial photosynthesis would reduce the global energy problem, decrease the dependence of the United States on foreign imports and fossil fuels, and address environmental concerns such as the high carbon dioxide concentration in the atmosphere. Information on the properties of the metal nanostructures will also be of value to other fields where nanostructures and photo-physics/chemistry/biology are widely used, such as medicine, environment, chemical production, military, and security. The proposed method is also potentially applicable to fertilizer production with sunlight to greatly impact agriculture. The proposed work will contribute to nurturing multidisciplinary scientists and engineers through research-based education.