F-Doped carbon nano-onion films as scaffold for highly efficient and stable Li metal anodes: a novel laser direct-write process. Issue 16 (12th April 2018)

• Record Type: Journal Article
• Authors: Puthusseri, Dhanya; Wahid, Malik; Basu, Aniruddha; Babar, Rohit; Kabir, Mukul; Ogale, Satishchandra
• Is Part Of: Nanoscale. Volume 10:Issue 16(2018)
• Page Start: 7630
• Page End: 7638
• Publication Date: 2018-04-12
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c7nr09656a
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : Direct writing of a fluorine-doped curved carbon nano-onion film on a Cu foil renders the Li metal anode with long cycle life, high Li-plating capacity, low-voltage hysteresis, and improved high current performance. Abstract : Li metal is the most promising choice for anode in high-energy rechargeable batteries, but the dendrite growth upon cycling leads to safety concerns and poor cycle life. Herein, we demonstrate a novel and scalable approach for direct writing of a thin layer of carbon nano-onions on copper substrate to stabilize the Li metal anode and prevent the dendrite growth. The F-doped carbon nano-onion film (F-CNOF) scaffold enables reversible electroplating for over 1500 hours (300 cycles) with a coulombic efficiency of ∼100%. The F-CNOF is capable of depositing Li equivalent to a capacity of 10 mA h cm −2 (gravimetric capacity 3218 mA h g −1 ) at 1 mA cm −2, operating at a high current density of 6 mA cm −2 . More importantly, these features of long-term cyclic stability and excellent rate capability are attributed to the very high curvature due to nano dimension (∼108 m −1 ) of the nano-onions that develop a very uniform Li flux due to the negative surface charge, thus preventing the dendrite formation. We have also shown via first-principles DFT calculations that the high curvature achieved herein can significantly enhance the binding energy of Li to the carbon surface, which helps to improve lithiophilicity. A full cell fabricated using Li4 Ti5 O12 as the positive electrode showed cyclic stability of 450 cycles.