457454 Graphene Nanoribbons As Conductive Pathways in Directly Deposited Silicon Nanofiber Anodes for High Performance Lithium-Ion Batteries
In the present work we are engineering the nanostructure of a silicon composite with graphene nanoribbons (GNRs) and polyvinyl alcohol (PVA) to create a reliable anode for lithium ion batteries. Silicon nanoparticles and GNRs are dispersed along PVA nanofibers via a water-based electrospinning process to directly form functional fiber mats on top of the copper current collector. This method is compatible with a role to role production, and bypasses several long-winded steps in the conventional paste-based electrode making. Physical and chemical properties of the nanoparticles and their dispersion affect the fiber morphology and ultimately electrochemical performance of the composite material. Graphene nanoribbons, made by unzipping carbon nanotubes, offer unique electrochemical and structural properties when inside the composite fibers. It was observed that GNRs outperform their precursor CNTs in terms of overall capacity and retention. The Silicon-GNR-PVA fiber anode exhibited an outstanding 2000 mAh/g at a rate of C/15 and 1200 at C/5 over 200 cycles. Inclusion of GNRs improved the structural stability and conductivity of the fibers, while protection of nanoparticles from the electrolyte offered by the polymer resulted in stable cycling of the directly deposited electrodes.
[1] C.-M. Wang, X. Li, Z. Wang, W. Xu, J. Liu, F. Gao, L. Kovarik, J.-G. Zhang, J. Howe, D. J. Burton, Z. Liu, X. Xiao, S. Thevuthasan, D. R. Baer, Nano Lett. 2012, 12, 1624.
[2] M. M., Ryu I, Wu H, Liu N, Hu L, Nix WD, Cui Y Yao Y, Nano Lett. 2011, 11, 2949.
[3] Y.-S. Hu, R. Demir-Cakan, M.-M. Titirici, J.-O. Müller, R. Schlögl, M. Antonietti, J. Maier, Angew. Chem. Int. Ed. 2008, 47, 1645.
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