Direct fabrication of SnO2- and MoO3-modified nanoporous TiO2-TiO-TiN composite films by hybrid anodization for high-safety lithium-ion battery anodes

Although modification with SnO2 or MoO3 is known to improve the properties of TiO2 -based anode materials for lithium-ion batteries (LIBs), simple fabrication methods are required to realize practical applications. Herein, we report a novel approach to fabricate SnO2 - or MoO3-modified nanoporous TiO2-TiO-TiN composite films by a hybrid anodization process in nitric-based aqueous solutions containing SnO32- or Mo7O246- ions. Concurrent anodic reactions resulted in Ti anodization to produce a composite film and the electrophoretic deposition of SnO2 or MoO3 colloids in the nanopores of the matrix film. Both TiO2 TiO-TiN@SnO2 and TiO2-TiO-TiN@MoO3 composite films exhibited enhanced discharge capacities (similar to 5-and 3-fold higher than that of the bare matrix film). This enhanced performance was attributed to the synergic effect of improved charge-transfer and additional capacity by depositing nanocrystalline SnO2 and MoO3 nanoparticles in the TiO2-TiO-TiN films, and the presence of nanoporous structures, which provided suitable Li+ transfer paths and reaction sites. The hybridization of nanoporous TiO2 films with SnO2 and MoO3 nanoparticles can simultaneously enhance the discharge capacity and address structural degradation issues in Sn- and MoO3-based electrodes. This simple hybrid anodization approach provides a promising strategy for designing high-power-density and high-safety anode materials for future LIBs. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

A novel hybrid anodization process was used to fabricate SnO2 or MoO3-modified nanoporous TiO2-TiO-TiN composite films, which exhibited enhanced discharge capacities and provided improved charge-transfer, additional capacity, suitable Li+ transfer paths, and reaction sites. This approach shows promise for designing high-power-density and high-safety anode materials for future LIBs.