Towards Advanced Sodium-Ion Batteries: Green, Low-Cost and High-Capacity Anode Compartment Encompassing Phosphorus/Carbon Nanocomposite as the Active Material and Aluminum as the Current Collector
Eliana Quartarone, Tobias Eisenmann, Matthias Kuenzel, Cristina Tealdi, Andrea Giacomo Marrani, Sergio Brutti, Daniele Callegari, Stefano Passerini
Abstract
Sodium-ion batteries (SIBs) are promising alternative to Lithium-ion batteries for massive stationary energy storage. To improve energy density, however, more performing active materials are needed. In order to allow sustainable scale-up, it is also mandatory to develop green products and processes. Herein, we report on anodes of phosphorus/carbon (P/C) nanocomposites prepared via High Energy Ball Milling (HEBM), a simple, powerful and easily scalable synthesis technique. The electrodes were prepared under oxygen-free atmosphere, using water as solvent, which enabled the use of aluminum (instead of copper) as current collector, implying significant cost reduction. The P/C nanocomposite obtained after 54 h HEBM resulted in excellent cycling stability, delivering very high specific capacity (2200 mAh g −1 , C/20) and showing good capacity retention after 120 cycles. A careful structural analysis (XRD, FESEM-EDS, XPS), revealed that long milling times strongly increased cycling stability due to: (i) significant decrease of P particle size inside the matrix and deep composite amorphization, which alleviates the buffering dimensional issues typical of black phosphorus; (ii) presence of defects in the carbonaceous component, which allows easier Na + insertion into the anode. Our results show that P/C nanocomposites are very promising anode materials for SIBs, paving the way for further exploitation of nano-architectures in SIBs technology.