3D Flower-like Nanospheres Constructed by Transition Metal Telluride Nanosheets as Sulfur Immobilizers for High-Performance Room-Temperature Na-S Batteries.

Room-temperature sodium-sulfur (RT Na-S) batteries hold immense promise as next-generation energy storage systems, owing to their exceptionally high theoretical capacity, abundant resources, eco-friendliness, and affordability. Nevertheless, their practical application is impeded by the shuttling effect of sodium polysulfides (NaPSs) and sluggish sulfur redox kinetics. In this study, an advanced strategy by designing 3D flower-like molybdenum telluride (MoTe2) as an efficient catalyst to promote sulfur redox for RT Na-S batteries is presented. The unique 3D flower-like MoTe2 effectively prevents NaPS shuttling and simultaneously offers abundant active catalytic sites facilitating polysulfide redox. Consequently, the obtained MoTe2/S cathode delivers an outstanding initial reversible capacity of 1015 mAh g-1 at 0.1 C, along with robust cycling stability of retaining 498 mAh g-1 at 1 C after 500 cycles. In addition, pouch cells are fabricated with the MoTe2 additive to deliver an ultrahigh initial discharge capacity of 890 mAh g-1 and remain stable over 40 cycles under practically necessary conditions, demonstrating the potential application in the commercialization of RT Na-S batteries.

Freestanding ReS2/Graphene Heterostructures as Binder-Free Anodes for Lithium-Ion Batteries.

It is still challenging to develop anode materials with high capacity and long cycling stability for lithium-ion batteries (LIBs). To address such issues, herein, for the first time, we present a three-dimensional and freestanding ReS2/graphene heterostructure (3DRG) as an anode synthesized via a one-pot hydrothermal method. The hybrid shows a hierarchically sandwich-like, nanoporous, and conductive three-dimensional (3D) network constructed by two-dimensional (2D) ReS2/graphene heterostructural nanosheets, which can be directly utilized as a freestanding and binder-free anode for LIBs. When the current density is 100 mA g-1, the 3DRG anode delivers a high reversible specific capacity of 653 mAh g-1. The 3DRG anode also delivers higher rate capability and cycling stability than the bare ReS2 anode. The markedly boosted electrochemical properties derive from the unique nanoarchitecture, which guarantees massive electrochemical active sites, short channels of lithium-ion diffusion, fast electron/ion transportation, and inhibition of the volume change of ReS2 for LIBs.