Jarosite Nanosheets Fabricated via Room-Temperature Synthesis as Cathode Materials for High-Rate Lithium Ion Batteries

Two-dimensional (2D) nanostructures of earth-abundant jarosite and their analogues were fabricated for the first time by a facile template-assisted redox co-precipitation method at room temperature. When evaluated as cathode materials for lithium ion batteries (LIBs), the as-prepared 2D materials deliver high capacities and good rate capability and cycling performance. As for jarosite KFe₃(SO₄)₂(OH)₆ nanosheets (KNSs), the reversible capacities of 117, 114, and 75 mAh g^–1 were achieved at 0.2, 1, and 10 C, respectively, 4–13 times higher than those of bulk sample. Capacity retentions of above 90% are both obtained after 50 cycles at 2 and 10 C. Such findings show that 2D jarosite nanostructures would be promising cathode materials for next-generation LIBs

Facile Synthesis of Highly Porous Ni–Sn Intermetallic Microcages with Excellent Electrochemical Performance for Lithium and Sodium Storage

Highly porous Ni₃Sn₂ microcages composed of tiny nanoparticles were synthesized by a facile template-free solvothermal method (based on Ostwald ripening and etching mechanism) for use as anode materials for high-capacity and high-rate-capability Li-ion and Na-ion batteries. The Ni₃Sn₂ porous microcages exhibit highly stable and substantial discharge capacities of the amount to 700 mA h g^–1 after 400 cycles at 0.2C and 530 mA h g^–1 after 1000 cycles at 1C for Li-ion battery anode. For Na-ions storage performance, a reversible capacity of approximate 270 mA h g^–1 is stably maintained at 1C during the first 300 cycles

Nanosheets of Earth-Abundant Jarosite as Novel Anodes for High-Rate and Long-Life Lithium-Ion Batteries

Nanosheets of earth-abundant jarosite were fabricated via a facile template-engaged redox coprecipitation strategy at room temperature and employed as novel anode materials for lithium-ion batteries (LIBs) for the first time. These 2D materials exhibit high capacities, excellent rate capability, and prolonged cycling performance. As for KFe₃(SO₄)₂(OH)₆ jarosite nanosheets (KNSs), the reversible capacities of above 1300 mAh g^–1 at 100 mA g^–1 and 620 mAh g^–1 after 4000 cycles at a very high current density of 10 A g^–1 were achieved, respectively. Moreover, the resulting 2D nanomaterials retain good structural integrity upon cycling. These results reveal great potential of jarosite nanosheets as low-cost and high-performance anode materials for next-generation LIBs

3D V₆O₁₃ Nanotextiles Assembled from Interconnected Nanogrooves as Cathode Materials for High-Energy Lithium Ion Batteries

Three-dimensional (3D) hierarchical nanostructures have been demonstrated as one of the most ideal electrode materials in energy storage systems owing to the synergistic combination of the advantages of both nanostructures and microstructures. In this work, 3D V₆O₁₃ nanotextiles built from interconnected 1D nanogrooves with diameter of 20–50 nm were fabricated via a facile solution-redox-based self-assembly route at room temperature, and the mesh size in the textile structure can be controllably tuned by adjusting the precursor concentration. It is suggested that the formation of 3D fabric structure built from nanogrooves is attributed to the rolling and self-assembly processes of produced V₆O₁₃ nanosheet intermediates. When evaluated as cathodes for lithium ion batteries (LIBs), the products delivered reversible capacities of 326 mAh g^–1 at 20 mA g^–1 and 134 mAh g^–1 at 500 mA g^–1, and a capacity retention of above 80% after 100 cycles at 500 mA g^–1. Importantly, the resulting textiles exhibit a specific energy as high as 780 Wh kg^–1, 44–56% higher than those of conventional cathodes, that is, LiMn₂O₄, LiCoO₂, and LiFePO₄. Furthermore, the 3D architectures retain good structural integrity upon cycling. Such findings reveal a great potential of V₆O₁₃ nanotextiles as high-energy cathode materials for LIBs

New Nanoconfined Galvanic Replacement Synthesis of Hollow Sb@C Yolk–Shell Spheres Constituting a Stable Anode for High-Rate Li/Na-Ion Batteries

In the current research project, we have prepared a novel Sb@C nanosphere anode with biomimetic yolk–shell structure for Li/Na-ion batteries via a nanoconfined galvanic replacement route. The yolk–shell microstructure consists of Sb hollow yolk completely protected by a well-conductive carbon thin shell. The substantial void space in the these hollow Sb@C yolk–shell particles allows for the full volume expansion of inner Sb while maintaining the framework of the Sb@C anode and developing a stable SEI film on the outside carbon shell. As for Li-ion battery anode, they displayed a large specific capacity (634 mAh g^–1), high rate capability (specific capabilities of 622, 557, 496, 439, and 384 mAh g^–1 at 100, 200, 500, 1000, and 2000 mA g^–1, respectively) and stable cycling performance (a specific capacity of 405 mAh g^–1 after long 300 cycles at 1000 mA g^–1). As for Na-ion storage, these yolk–shell Sb@C particles also maintained a reversible capacity of approximate 280 mAh g^–1 at 1000 mA g^–1 after 200 cycles

New Nanoconfined Galvanic Replacement Synthesis of Hollow Sb@C Yolk–Shell Spheres Constituting a Stable Anode for High-Rate Li/Na-Ion Batteries

In the current research project, we have prepared a novel Sb@C nanosphere anode with biomimetic yolk–shell structure for Li/Na-ion batteries via a nanoconfined galvanic replacement route. The yolk–shell microstructure consists of Sb hollow yolk completely protected by a well-conductive carbon thin shell. The substantial void space in the these hollow Sb@C yolk–shell particles allows for the full volume expansion of inner Sb while maintaining the framework of the Sb@C anode and developing a stable SEI film on the outside carbon shell. As for Li-ion battery anode, they displayed a large specific capacity (634 mAh g^–1), high rate capability (specific capabilities of 622, 557, 496, 439, and 384 mAh g^–1 at 100, 200, 500, 1000, and 2000 mA g^–1, respectively) and stable cycling performance (a specific capacity of 405 mAh g^–1 after long 300 cycles at 1000 mA g^–1). As for Na-ion storage, these yolk–shell Sb@C particles also maintained a reversible capacity of approximate 280 mAh g^–1 at 1000 mA g^–1 after 200 cycles