Ultralong Sb₂Se₃ Nanowire-Based Free-Standing Membrane Anode for Lithium/Sodium Ion Batteries

Metal chalcogenides have emerged as promising anode materials for lithium ion batteries (LIBs) and sodium ion batteries (SIBs). Herein, a free-standing membrane based on ultralong Sb₂Se₃ nanowires has been successfully fabricated via a facile hydrothermal synthesis combined with a subsequent vacuum filtration treatment. The as-achieved free-standing membrane constructed by pure Sb₂Se₃ nanowires exhibits good flexibility and integrity. Meanwhile, we investigate the lithium and sodium storage behavior of the Sb₂Se₃ nanowire-based free-standing membrane. When applied as the anode for LIBs, it delivers a reversible capacity of 614 mA h g^–1 at 100 mA g^–1, maintaining 584 mA h g^–1 after 50 cycles. When applied as the anode for SIBs, it delivers a reversible capacity of 360 mA h g^–1 at 100 mA g^–1, retaining 289 mA h g^–1 after 50 cycles. Such difference in electrochemical performance can be attributed to the more complex sodiation process relative to the corresponding lithiation process. This work may provide insight on developing Sb₂Se₃-based anode materials for high-performance LIBs or SIBs

Porous and Low-Crystalline Manganese Silicate Hollow Spheres Wired by Graphene Oxide for High-Performance Lithium and Sodium Storage

Herein, a graphene oxide (GO)-wired manganese silicate (MS) hollow sphere (MS/GO) composite is successfully synthesized. Such an architecture possesses multiple advantages in lithium and sodium storage. The hollow MS structure provides a sufficient free space for volume variation accommodation; the porous and low-crystalline features facilitate the diffusion of lithium ions; meanwhile, the flexible GO sheets enhance the electronic conductivity of the composite to a certain degree. When applied as the anode material for lithium-ion batteries (LIBs), the as-obtained MS/GO composite exhibits a high reversible capacity, ultrastable cyclability, and good rate performance. Particularly, the MS/GO composite delivers a high capacity of 699 mA h g^–1 even after 1000 cycles at 1 A g^–1. The sodium-storage performance of MS/GO has been studied for the first time, and it delivers a stable capacity of 268 mA h g^–1 after 300 cycles at 0.2 A g^–1. This study suggests that the rational design of metal silicates would render them promising anode materials for LIBs and SIBs

ZnSe Microsphere/Multiwalled Carbon Nanotube Composites as High-Rate and Long-Life Anodes for Sodium-Ion Batteries

Sodium-ion batteries (SIBs) are considered as one of the most favorable alternative devices for sustainable development of modern society. However, it is still a big challenge to search for proper anode materials which have excellent cycling and rate performance. Here, zinc selenide microsphere and multiwalled carbon nanotube (ZnSe/MWCNT) composites are prepared via hydrothermal reaction and following grinding process. The performance of ZnSe/MWCNT composites as a SIB anode is studied for the first time. As a result, ZnSe/MWCNTs exhibit excellent rate capacity and superior cycling life. The capacity retains as high as 382 mA h g^–1 after 180 cycles even at a current density of 0.5 A g^–1. The initial Coulombic efficiency of ZnSe/MWCNTs can reach 88% and nearby 100% in the following cycles. The superior electrochemical properties are attributed to continuous electron transport pathway, improved electrical conductivity, and excellent stress relaxation

Copper Silicate Hydrate Hollow Spheres Constructed by Nanotubes Encapsulated in Reduced Graphene Oxide as Long-Life Lithium-Ion Battery Anode

Hierarchical copper silicate hydrate hollow spheres-reduced graphene oxide (RGO) composite is successfully fabricated by a facile hydrothermal method using silica as <i>in situ</i> sacrificing template. The electrochemical performance of the composite as lithium-ion battery anode was studied for the first time. Benefiting from the synergistic effect of the hierarchical hollow structure and conductive RGO matrix, the composite exhibits excellent long-life performance and rate capability. A capacity of 890 mAh/g is achieved after 200 cycles at 200 mA/g and a capacity of 429 mAh/g is retained after 800 cycles at 1000 mA/g. The results indicate that the strategy of combining hierarchical hollow structures with conductive RGO holds the potential in addressing the volume expansion issue of high capacity anode materials