title: Hierarchical Carbon with High Nitrogen Doping Level: A Versatile Anode and Cathode Host Material for Long-Life Lithium-Ion and Lithium-Sulfur Batteries.
abstract: Nitrogen-rich carbon with both a turbostratic microstructure and meso/macroporosity was prepared by hard templating through pyrolysis of a tricyanomethanide-based ionic liquid in the voids of a silica monolith template. This multifunctional carbon not only is a promising anode candidate for long-life lithium-ion batteries but also shows favorable properties as anode and cathode host material owing to a high nitrogen content (>8% after carbonization at 900 °C). To demonstrate the latter, the hierarchical carbon was melt-infiltrated with sulfur as well as coated by atomic layer deposition (ALD) of anatase TiO2, both of which led to high-quality nanocomposites. TiO2 ALD increased the specific capacity of the carbon while maintaining high Coulombic efficiency and cycle life: the composite exhibited stable performance in lithium half-cells, with excellent recovery of low rate capacities after thousands of cycles at 5C. Lithium-sulfur batteries using the sulfur/carbon composite also showed good cyclability, with reversible capacities of ∼700 mA·h·g(-1) at C/5 and without obvious decay over several hundred cycles. The present results demonstrate that nitrogen-rich carbon with an interconnected multimodal pore structure is very versatile and can be used as both active and inactive electrode material in high-performance lithium-based batteries.
authors: Christian
authors: C
authors: Reitz
authors: Ben
authors: B
authors: Breitung
authors: Artur
authors: A
authors: Schneider
authors: Di
authors: D
authors: Wang
authors: Institute of Physical Chemistry, Justus Liebig University Giessen , Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
authors: Martin
authors: M
authors: von der Lehr
authors: Institute of Physical Chemistry, Justus Liebig University Giessen , Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
authors: Thomas
authors: T
authors: Leichtweiss
authors: Institute of Physical Chemistry, Justus Liebig University Giessen , Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
authors: Jürgen
authors: J
authors: Janek
authors: Helmholtz Institute Ulm for Electrochemical Energy Storage , Helmholtzstrasse 11, 89081 Ulm, Germany.
authors: Horst
authors: H
authors: Hahn
authors: Torsten
authors: T
authors: Brezesinski
keywords: N-doped carbon; atomic layer deposition; hard templating; rechargeable battery; sulfur; titania