弹性红磷基复合电极材料的磁控合成组装及其储钠机理研究

Solving the stability in the preparation process and the volume expansion problem during cycling for red P based composite electrode material are urgently targeted pursuits. The magnetic force can promote the synthesis efficiency and resists the volume expansion force. At the same time, the incorporation of red P with carbon, the application of surface modification technique and the well-designed structure can improve the conductivity of such composite electrode material and increase the electrochemical reactive sites, which are favorable for the enhancements of electrochemical performance. The magnetic facilitated preparation and assembly of electrodes will be validated by investigating supermagnetic Fe3O4/C/P. As for the volume swelling force, it is prohibited by the electrostatic force during the sodiation and desodiation process. Such magnetic controlled technique will be further optimized by the investigation of ferromagnetic Fe/Fe3O4/C/P. Also the universality of the rule of such magnetic controlled method will be verified by the investigation of the ferromagnetic MnO2/Ni0.5Co0.5Fe2O4/C/P and NaMnO2/Ni0.5Co0.5Fe2O4/C/P composites. The detailed mechanism for sodium ion batteries will be explored and the kinetics sodium ion diffusion model will be calculated as the increment of migration vacancies. The study results will provide theoretical foundation and experimental technique for the magnetic controlled material preparation, the optimum structure design and optimized electrochemical behaviors.

红磷基复合电极材料的稳定性和体积膨胀问题亟待解决。利用磁控调节技术可解决红磷的稳定性问题和体积膨胀问题。将红磷和碳进行复合，结合表面修饰技术和合理的结构设计，改善材料的导电性，增加电化学反应活性位。引入超顺磁Fe3O4作为磁源，制备Fe3O4/C/P，磁控提高红磷合成的稳定性，并且利用磁控优化电池组装技术。在充放电过程中，材料所受的静电作用力可抑制体积膨胀现象。引入磁性更强的Fe/Fe3O4/C/P, 进一步改善此磁控优化合成和电池组装技术。在此基础上,通过铁磁性MnO2/Ni0.5Co0.5Fe2O4/C/P和NaMnO2/Ni0.5Co0.5Fe2O4/C/P，探究此技术的普遍适用性。研究上述模型的储钠机理，计算随钠迁移空位的增多，钠离子扩散的动力学模型。研究成果将为磁控材料的合成、材料结构的优化设计以及磁控优化电池性能提供一定的理论基础和实验技术。

本项目研发了低成本，绿色高效的链状的多孔状Fe3O4/C/P钠电池负极材料。外加磁场，提高材料合成效率和优化电池组装技术。在制备过程中，使红磷沉积变得更加可控， 提高红磷与白磷的转化率，将尺寸均一的红磷颗粒均匀沉积在碳基体上。在电池组装方面，磁控活性物质在集流体上进行不同排列，研究洛伦兹力与电子传导能力和离子扩散能力的构效性以及材料静电作用力对体积膨胀的显著抑制效果。引入外界刺激源，同时达到优化材料制备和电池组装技术的目的。本项目涉及化学、材料和物理等交叉领域，研究成果将为红磷基储能材料制备，和磁控改善电极材料电化学性能提供新思路和实验方法，对于研发可持续储能技术有重要理论和现实意义。