Correlating Shear and Drying Physics to Carbon Microstructure and Electrochemical Performance in Composite Electrodes

由颗粒-聚合物复合材料组成的电极用于各种技术应用，包括电动汽车、微电子和环境修复。 穿过电极的离子和电极传输的效率强烈地影响电极的整体性能。 通过使颗粒的浓缩悬浮液在表面上流动并使悬浮液干燥来制造电极。 在表面处形成的所得微粒微结构影响最终电极的电荷传输。 该项目的目标是可视化电极制造的流动、涂覆和干燥过程之前、期间和之后的微观结构演变。 最终的薄膜将进行表征和测试，以帮助了解加工条件和电极性能之间的关系。 该研究团队将为不同学术水平的学生提供参与研究的机会，包括高中生，他们将通过德雷克塞尔的星星和星星LITE项目被招募到该项目中。该项目的假设是，纳米级碳颗粒决定了湿浆料和干电极微观结构的性质，这强烈影响了电荷传输。 提出了在涂覆和干燥过程中可视化颗粒位置及其连通性的技术。为了实现这一点，将碳涂覆的金属纳米颗粒接种到电极浆料中，使得可以获得浆料的三维断层图像和涂层的二维元素图。微观结构可视化将与流动和干燥过程中浆料阻抗的原位测量相结合，这将使整个制造过程中颗粒连通性的动态表征成为可能。该项目的成果将使从业者更好地了解如何操纵材料成分和加工条件以形成更有效的电极。该奖项反映了NSF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。

Electrodes composed of particle-polymer composites are used in a variety of technological applications including electric vehicles, microelectronics, and environmental remediation. The efficiency of ion and electrode transport across the electrode strongly affects the overall performance of the electrode. The electrodes are fabricated by flowing a concentrated suspension of particles over a surface and allowing the suspension to dry. The resulting particulate microstructure formed at the surface influences charge transport of the final electrode. The goal of this project is to visualize the evolution of the microstructure before, during and after the flow, coating and drying processes of electrode manufacturing. The final films will be characterized and tested to help understand the relationship between processing conditions and electrode performance. The research team will provide opportunities for students at various academic levels to participate in the research, including high school students who will be recruited to the project through the STAR and STAR LITE programs at Drexel.This hypothesis underlying this project is that nanometer-scale carbon particles dictate properties of the wet slurry and dry electrode microstructure, which strongly affect charge transport. Techniques are proposed to visualize the location of the particles and their connectivity during the coating and drying processes. To accomplish this, carbon-coated metallic nanoparticles will be seeded into the electrode slurry so that three-dimensional tomographic images of the slurry and two-dimensional elemental maps of the coating can be obtained. Microstructure visualization will be combined with in-situ measurements of slurry impedance during flow and drying, which will enable dynamic characterization of particle connectivity throughout the manufacturing process. Results of this project will provide practitioners with a better understanding of how material compositions and processing conditions can be manipulated to form more efficient electrodes.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.