Fundamental Understanding of Redox Characteristics of Carbonyl Materials for Energy Storage Applications

对于固定的大规模应用，如电网负荷均衡和间歇性可再生能源的储能，越来越需要具有成本效益和高性能的电化学储能。然而，目前可充电锂离子电池的成本和性能限制了它们在大规模储能应用中的应用。碳基有机化合物电极具有高能量密度、有益的环境足迹和利用丰富的地球资源等优点，具有作为大规模储能系统的潜力。现有的有机电极材料存在倍率性能低、循环稳定性差的问题。这一基础研究项目将为设计具有优异电荷存储性能的新型有机电极提供新知识。本研究将通过计算与实验相结合的方法建立有机电极材料的结构-性能关系。关键的创新是，新的有机电极将被设计在纳米级的高导电性碳基板上，以实现高能量和高功率密度。高性能有机电极也可用于储能应用，包括便携式电源和电动汽车。未来的能源科学工作者将受益于涉及纳米科学、电化学和电化学工程、材料科学和计算科学的研究经验。拓展活动将包括基于协同计算实验活动的研究生和本科生研究项目，以及针对不同背景的K-12学生开发可充电电池教育模块。有机电极材料在可充电锂离子电池中具有理论容量大、成本低等优点。近年来对有机电极材料的研究主要集中在羰基材料上。然而，这些有机材料通常具有缓慢的速率性能和较差的循环稳定性。通过在碳纳米管和石墨烯等导电碳基质上进行分子设计，羰基化合物的电荷存储性能将得到显著提高。本研究的目的是了解导电碳衬底上羰基聚合物的多尺度化学结构与其电荷存储性能的关系。为了实现这一目标，研究小组将1)利用电化学聚合工艺在导电衬底上合成羰基聚合物；2)利用分子动力学（MD）模拟方法研究羰基聚合物最可能的结构；3)利用密度泛函理论（DFT）预测羰基聚合物的电荷存储特性；4)利用电化学技术评价羰基聚合物电极的电荷存储性能。这项基础研究将用于确定理想的羰基电极，具有优异的电荷存储性能/性能，可直接用于高性能和经济高效的可充电电池。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Cost-effective and high-performance electrochemical energy storage is increasingly needed for stationary, large-scale applications such as for grid load leveling and for energy storage for intermittent renewable energy sources. However, current cost and performance of rechargeable lithium-ion batteries limit their use in large-scale energy storage applications. Carbon-based organic compound electrodes have the potential to serve as large-scale energy storage systems, owing to their advantages, including high energy density, beneficial environmental footprint, and use of earth-abundant resources. Current organic electrode materials suffer from slow rate-performance and poor cycling stability. This fundamental research project will result in new knowledge for designing new organic electrodes with superior charge storage performance. The research will establish the structure-performance property relationships of organic electrode materials by combining computations and experiments. The key innovation is that the new organic electrodes will be designed at the nanoscale on highly conductive carbon substrates to achieve both high energy and high-power densities. High-performance organic electrodes can also be used for energy storage applications including portable power and electric vehicles. The future energy science workforce will benefit through a research experience involving nanoscience, electrochemistry and electrochemical engineering, materials science, and computational science. The outreach activities will include graduate and undergraduate student research projects based on synergistic computational-experimental activities and the development of an educational module on rechargeable batteries targeted towards K-12 students from diverse backgrounds. Organic electrode materials have advantages over conventional inorganic electrodes for rechargeable lithium-ion battery applications in terms of high theoretical capacity and low-cost. Recent research efforts on organic electrode materials have been focused on carbonyl materials. However, these organic materials generally have slow rate-performance and poor cycling stability. Charge storage performance of carbonyl compounds may be significantly improved through the molecular design on conductive carbon substrates, such as carbon nanotubes and graphene. The goal of this research is to understand the relationship of the multiscale chemical structures of carbonyl-polymers on conductive carbon substrates with their charge storage properties and performances. To achieve this goal, the research team will 1) synthesize carbonyl-polymers on the conductive substrates using electrochemical polymerization processes; 2) investigate the most probable structure of carbonyl-polymer using the molecular dynamics (MD) simulation method; 3) predict the charge storage properties of carbonyl-polymer using Density Functional Theory (DFT) methods; and 4) evaluate charge storage properties/performance of carbonyl-polymer electrodes using electrochemical techniques. This fundamental study will be used to identify the ideal carbonyl-based electrodes for superior charge storage properties/performances, which can be directly used for high-performance and cost-effective rechargeable batteries.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.