Aerosol-Assisted Synthesis of Colloidal Aggregates with Different Morphology: Toward the Electrochemical Optimization of Li3VO4 Battery Anodes Using Scalable Routes

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• 作者：Pedro Tartaj ; Jose M. Amarilla ; Maria B. Vazquez-Santos
• 刊名：Chemistry of Materials
• 出版年：2016
• 出版时间：February 9, 2016
• 年：2016
• 卷：28
• 期：3
• 页码：986-993
• 全文大小：522K
• ISSN：1520-5002

文摘

The improvement of properties through strict morphology control often requires the use of difficult to scale up synthesis routes. Thus, a compromise between scalability and morphology control is required to partially exploit the advantages of this control in materials functionality. Here, we show that a scalable and continuous route (aerosol route) is able to produce Li₃VO₄ colloidal aggregates with different morphology (spherical and platelet-like) using easy to handle economic precursors (V₂O₅, LiOH, and LiNO₃ in stoichiometric amounts). The key for these differences in morphology resides on controlling the nature of the intermediate stages that can occur during particle formation in aerosol synthesis. We also show that the electrochemical response of Li₃VO₄ is strongly dependent on morphology. Thus, optimization of morphology allows building anodes that to our knowledge outperform other reported Li₃VO₄ anodes and even compete with most of the reported Li₃VO₄/C composites at adequate high rates (2–8 A/g). Finally, we have developed a simple and scalable coating protocol (suspensions with solid concentrations of 100 g/L are used) that additionally improves the long-term stability of the optimized anodes. Combination of the two scalable methods leads to Li₃VO₄ anodes that operating at a safe cutoff voltage of 0.2 V can retain a high capacity (280 mAh/g) with excellent coulumbic efficiency (>99.9%), even after 500 cycles at a competitive rate (2 A/g discharge–charge).