EFRI-RESTOR: Thermochemical Routes to Efficient and Rapid Production of Solar Fuels

该项目的目标是利用热化学方法将光子能量转化为化学键来改造和扩大国家的可再生能源储存能力。该方法依赖于选定的非化学计量金属氧化物，特别是氧化铈（ceria）的储存和释放氧气的能力，以响应温度的变化，其中热循环是由暴露在太阳辐射下引起的。当引入适当的反应物气体时，所产生的化学计量变化可以直接用于燃料生产。这样的燃料，反过来，可以用于发电需求，采用传统的燃烧或燃料电池。pi将建立在最近对非化学计量氧化物热化学循环行为的理解上的突破，并扩大努力，以便(a)获得目标热力学和动力学特性，(b)在原型反应堆中展示技术可行性，在经过验证的模型和测量的材料特性的基础上设计和优化。材料成功的关键是提高反应动力学和调整氧化还原反应的热力学，以便在与反应堆建筑材料和有利于高热回收的大气下的太阳能聚光光学兼容的温度下运行。这两个目标都将通过在宿主氧化物中引入过渡金属掺杂剂和其他替代阳离子来实现，这些修饰可以进一步提高太阳吸收率。除了对基本材料特性的操纵之外，具有工程结构的多孔材料将被用于增强热化学循环特性，例如，通过为快速反应动力学提供高表面积，确保最小的气体流动阻力，并提供可调的太阳能吸收特性。为了实现从台式实验到在集中太阳辐射下运行的工作原型的过渡，将采用越来越复杂的热堆和太阳热堆模型。热化学太阳能存储方法具有大规模实施的潜力，因此具有广泛的影响，因为该方法使用相对丰富的地球材料，并且效率可以非常高。除了提出技术上可行的方法之外，该建议还为下一代能源科学家和技术人员的教育和培训提供了一个多学科和国际环境。支持该项目的2010财年eri - restor课题由美国国家科学基金会（NSF）工程（ENG）、数学与物理科学（MPS）、社会、行为与经济科学（SBE）、计算机与信息科学与工程理事会与美国能源部（DOE）合作赞助。

The objective of this project is to transform and expand the nation's renewable energy storage capacity using a thermochemical approach for converting the energy of photons into chemical bonds. The approach relies on the capacity of selected nonstoichiometric metal oxides, specifically cerium oxide (ceria), to store and release oxygen in response to changes in temperature, where the thermal cycling is induced by exposure to solar radiation. The resulting stoichiometry changes can be directly utilized for fuel production when coupled with the introduction of appropriate reactant gases. Such fuel, in turn, can be used for electricity generation on demand, employing either conventional combustion or fuel cells. The PIs will build on recent breakthroughs in the understanding of thermochemical cycling behavior of nonstoichiometric oxides and expand the effort so as to (a) attain targeted thermodynamic and kinetic characteristics and (b) demonstrate technical feasibility in a prototype reactor, designed and optimized on the basis of validated models and measured material properties. Critical to the materials success is enhancing reaction kinetics and tuning the thermodynamics of the redox reactions so as to enable operation at temperatures compatible with reactor construction materials and solar concentrating optics under atmospheres conducive to high heat recovery. Both objectives will be pursued through the introduction of transition metal dopants and other substitutional cations into the host oxide, modifications which can further enhance solar absorptance. Beyond the manipulation of the fundamental materials properties, porous materials with engineered architectures will be employed to enhance thermochemical cycling characteristics, by, for example, providing high surface area for rapid reaction kinetics, ensuring minimal resistance to gas flow, and providing tunable solar absorption properties. A hierarchy of thermal and solar-thermal reactor models with increasing complexity will be employed to achieve the transition from benchtop experiments to a working prototype operated under concentrated solar radiation. A thermochemical approach to solar energy storage has the potential for large-scale implementation and hence broad impact because the method employs relatively earth-abundant materials, and the efficiency can be extremely high. Beyond the advancement of a technically feasible approach, the proposal provides a multi-disciplinary and international environment for the education and training of the next generation of energy scientists and technologists.The FY 2010 EFRI-RESTOR Topic that supports this project was sponsored by the US National Science Foundation (NSF) Directorates for Engineering (ENG), Mathematical and Physical Sciences (MPS) and Social, Behavioral and Economic Sciences (SBE), and Computer & Information Science and Engineering in collaboration with the US Department of Energy (DOE).