Hierarchical Porous Nanosheets Constructed by Graphene‐Coated, Interconnected TiO₂ Nanoparticles for Ultrafast Sodium Storage

Abstract

Sodium-ion batteries (SIBs) are considered promising next-generation energy storage devices. However, a lack of appropriate high-performance anode materials has prevented further improvements. Here, a hierarchical porous hybrid nanosheet composed of interconnected uniform TiO nanoparticles and nitrogen-doped graphene layer networks (TiO @NFG HPHNSs) that are synthesized using dual-functional C N nanosheets as both the self-sacrificing template and hybrid carbon source is reported. These HPHNSs deliver high reversible capacities of 146 mA h g at 5 C for 8000 cycles, 129 mA h g at 10 C for 20 000 cycles, and 116 mA h g at 20 C for 10 000 cycles, as well as an ultrahigh rate capability up to 60 C with a capacity of 101 mA h g . These results demonstrate the longest cyclabilities and best rate capability ever reported for TiO -based anode materials for SIBs. The unprecedented sodium storage performance of the TiO @NFG HPHNSs is due to their unique composition and hierarchical porous 2D structure.

In Situ Fabrication of Branched TiO2/C Nanofibers as Binder‐Free and Free‐Standing Anodes for High‐Performance Sodium‐Ion Batteries

“…Transitional metal oxide nanomaterials have drawn considerable attention as anode materials for SIBs owing to their distinct reaction mechanism, abundant active sites, and short diffusion pathways . Among them, titanium dioxide (TiO 2 ) has been extensively studied in recent years due to its natural abundance, low cost, environment friendliness, attractive theoretical specific capacity of 335 mA h g −1 , and superior structure's stability during the charge/discharge processes . Noticeably, the anatase TiO 2 has displayed excellent electrochemically activity for Na + storage, attributing to its favorable 2D diffusion pathways and proper interstitial sites for Na + accommodation .…”

TiO2‐Coated Interlayer‐Expanded MoSe2/Phosphorus‐Doped Carbon Nanospheres for Ultrafast and Ultralong Cycling Sodium Storage

“…[24][25][26][27][28][29] Although its theoretical specific capacity is fairly low, it can serve as an effective protective layer for other electrode materials with severe volume expansion, such as metal oxides or metal sulfides through smart hybridization. [24][25][26][27][28][29] Although its theoretical specific capacity is fairly low, it can serve as an effective protective layer for other electrode materials with severe volume expansion, such as metal oxides or metal sulfides through smart hybridization.…”

Heterostructured TiO2 Spheres with Tunable Interiors and Shells toward Improved Packing Density and Pseudocapacitive Sodium Storage

“…[2][3][4] Similar with the performance limit issues in LIB systems, the key challenges for the application and commercialization of NIBs are regarded as the appropriate electrode material selection and design. [8][9][10][11][12][13] However, the relatively low specific capacity and inferior rate capability of TiO 2 -based anode materials make them still have the necessity of promotion and optimization. [8][9][10][11][12][13] However, the relatively low specific capacity and inferior rate capability of TiO 2 -based anode materials make them still have the necessity of promotion and optimization.…”