CAREER: Dynamic Phenomena in Complex Oxides During Electrochemical Processes

非技术描述：能源储存是实现环境友好型交通运输和可再生能源经济部署的关键。所有的电化学储能和转换材料都起着“活”系统的作用(电池、准电容器和燃料电池)，在充放电过程中电子和离子在其中运动。这些电子和离子运动经常引发缺陷的产生和相变，从而导致材料的能量密度和倍率能力发生显著变化。在电化学过程中建立这些动力学机制的基本基础将加速创造具有优异储能和转换性能的新的合成材料。技术细节：本研究的目标是一系列具有可逆储能能力的过渡金属氧化物xA_2MnO_3(1-x)Ay(NiMn)O_2(A=Li~+，Na~+)O_2的系统合成、结构表征和性能评价。这些氧化物具有有趣而复杂的特征，包括循环时的纳米级相分离和不同电荷状态下的动态阳离子重新分布，这显著影响了客体物种的迁移率。当释放客体物种时发生的还原-氧化过程不仅可以改变阳离子的分布，而且还可以改变材料内的固-固界面，这对电极的传输性质和结构稳定性是至关重要的。所开发的框架可作为控制固态储能材料中的动态现象的基础；这些知识对于设计和开发新材料具有关键和变革性，这些新材料将在电化学储能和转换系统中实现更高、更快的储能和更长的寿命。这笔赠款的更广泛影响与研究目标相结合。国际和平协会的教育努力包括a)。通过工具、实例和动手实验室经验，垂直整合大学前、本科生和研究生的教育和培训。培养学生对文化和教育背景、经验和研究方法的多样性的强烈认识和欣赏，以直接影响加州大学圣迭戈分校校园的多样性；以及c)在国际科学和工程环境中从事教学和研究，包括组织年度国际研讨会和以研究为重点的交流计划。

NON-TECHNICAL DESCRIPTION: Energy storage is the enabling key to the environmentally-friendly transportation and the economic deployment of renewable energy sources. All electrochemical energy storage and conversion materials function as 'living' systems (batteries, pseudocapacitors and fuel cells), within which electrons and ions are moving during charge and discharge. These electronic and ionic motions often trigger defect generation and phase transformations, and consequently result in significant changes in energy density and rate capability of the materials. Establishing the fundamental basis for these dynamical mechanisms during electrochemical processes will accelerate the creation of new synthetic materials with superior energy storage and conversion properties. TECHNICAL DETAILS: This research targets the systematic synthesis, structural characterization and properties evaluation of a series of transition metal oxides xA2MnO3(1-x)Ay(NiMn)O2 (A=Li+, Na+ the mobile species) that are capable of storing energy reversibly. These oxides have intriguing and complex features including nanometer-scale phase separation upon cycling and dynamic cation redistribution at various state of charge, that significantly affect the mobility of the guest species. The reduction-oxidation processes that occur upon releasing the guest species, not only may alter the cation distributions, but also modify the solid-solid interfaces within the material, which are critical to the transport properties as well as the structural stability of the electrodes. The developed framework can be applied as the basis for controlling the dynamic phenomena in solid-state materials for energy storage; such knowledge is critical and transformational to design and develop new materials that will allow higher and faster energy storage and longer lifetime in electrochemical energy storage and conversion systems. The broader impacts of this grant are integrated with the research objectives. The PI's education efforts include a). Vertically integrating precollegiate, undergraduate and graduate education and training through tools, practical examples and hands-on laboratory experiences b). Fostering a strong awareness and appreciation for diversity of cultural and educational backgrounds and experience and research approaches among the students to directly impact the diversity on UCSD campus, and c). Engaging in teaching and research in an international science and engineering environment, including organizing an annual international workshop and research-focused exchange program.