Mesoporous and Nanostructured TiO₂ layer with Ultra‐High Loading on Nitrogen‐Doped Carbon Foams as Flexible and Free‐Standing Electrodes for Lithium‐Ion Batteries

Abstract

A simple and green method is developed for the preparation of nanostructured TiO supported on nitrogen-doped carbon foams (NCFs) as a free-standing and flexible electrode for lithium-ion batteries (LIBs), in which the TiO with 2.5-4 times higher loading than the conventional TiO -based flexible electrodes acts as the active material. In addition, the NCFs act as a flexible substrate and efficient conductive networks. The nanocrystalline TiO with a uniform size of ≈10 nm form a mesoporous layer covering the wall of the carbon foam. When used directly as a flexible electrode in a LIB, a capacity of 188 mA h g is achieved at a current density of 200 mA g for a potential window of 1.0-3.0 V, and a specific capacity of 149 mA h g after 100 cycles at a current density of 1000 mA g is maintained. The highly conductive NCF and flexible network, the mesoporous structure and nanocrystalline size of the TiO phase, the firm adhesion of TiO over the wall of the NCFs, the small volume change in the TiO during the charge/discharge processes, and the high cut-off potential contribute to the excellent capacity, rate capability, and cycling stability of the TiO /NCFs flexible electrode.

Advanced 3D Current Collectors for Lithium‐Based Batteries

“…Thermal pyrolysis of commercially available polymer foam (melamine foam, melamine formaldehyde, and polyurethane foam) has been suggested to be a more convenient and cost‐effective method to obtain the covalently connected 3D carbon network than CVD since the metal template can be avoided in this method . The structure constituents of the pyrolytic carbon network are mostly amorphous carbon due to the low carbonization temperature of <900 °C.…”

“…The structure constituents of the pyrolytic carbon network are mostly amorphous carbon due to the low carbonization temperature of <900 °C. Cai and co‐workers reported a N‐doped carbon foam (NCF) as a freestanding and flexible current collector by carbonization of melamine foam . Due to the low areal mass density of the NCF (1.77 mg cm −2 ) and the 3D interconnected carbon network, the mass loading and mass fraction of the active material (TiO 2 ) reached 5 mg cm −2 and 76 wt%, respectively.…”

Strategies for Building Robust Traffic Networks in Advanced Energy Storage Devices: A Focus on Composite Electrodes

“…Therefore, strategies on how to design the porous structures of electrode scaffolds to improve the mechanical properties and support higher loading of AMs are in critical need. Carbon foams and porous carbon frameworks with small pores provide a good solution to the above issue . For example, Zhang and co‐workers reported a type of porous carbon foam based on CMK‐3 hard template for LTO anode as shown in Figure a .…”

Alumina nanocoating of polymer separators for enhanced thermal and electrochemical performance of Li–ion batteries

“…Lithium ion batteries (LIBs) are the primary choice for portable devices because of their high energy and power density, long cycle life, relatively low cost, and minor memory effects . However, safety is still a major issue hindering the widespread utilization of LIBs; specifically, for large‐scale energy applications .…”