Long-Life, High-Rate Rechargeable Lithium Batteries Based on Soluble Bis(2-pyrimidyl) Disulfide Cathode

Reconstructable Carbon Monolayer-MoS2 Intercalated Heterostructure Enabled by Atomic Layers-Confined Topotactic Transformation for Ultrafast Lithium Storage

The intercalation structure of two-dimensional materials with expanded interlayer distance can facilitate mass transport, which is promising in fast-charging lithium-ion batteries (LIBs). However, the designed intercalation structures will be pulverized and destroyed under tough working conditions, causing overall performance deterioration of the batteries. Here, we present that an intercalated heterostructure made of the typical layered material of MoS2 intercalated by N-doped graphene-like carbon monolayer (MoS2/g-CM) through a polymer intercalation strategy exhibits a unique behavior of reversible reconstructability as an LIB anode during cycling. A mechanism of "carbon monolayers-confined topotactic transformation" is proposed, which is evidenced by substantial in/ex situ characterizations. The intercalated heterostructure of MoS2/g-CM featuring a reconstructable property and efficient interlayer electron/ion transport exhibits an unprecedented rate capability up to 50 A g-1 and outstanding long cyclability. Moreover, the proposed strategy based on g-CM intercalation has been extended to the MoSe2 system, also realizing reconstructability of the intercalated heterostructure and improved LIB performance, demonstrating its versatility and great potential in applications.

Phenyl Tellurosulfides as Cathode Materials for Rechargeable Lithium Batteries

Phenyl ditelluride (PDTe) as a cathode material for rechargeable batteries has a low specific capacity (130.9 mAh g-1) due to limited active sites (two). To increase its capacity, additional active species need to be added to the structure of PDTe, like sulfur. Here, phenyl tellurosulfide (PDTeS) and phenyl tellurodisulfide (PDTeS2) can be formed via addition reactions and have specific capacities of 242.8 and 339.6 mAh g-1, respectively. The products are characterized by mass spectrometry and Raman spectroscopy. The Li/PDTeSn (n = 1-2) cells exhibit high material utilization (>85%) and unique redox mechanism. They can be cycled stably for more than 1000 cycles at an areal mass loading of 1.1 mg cm-2 and maintain capacity retentions of >72% after 100 cycles with PDTeSn loading of ∼6 mg cm-2. Moreover, the Li/PDTeS2 cell achieves a specific energy of up to 695 Wh kg-1 even when the electrolyte/PDTeS2 ratio is as low as 2.5 μL mg-1. The successful synthesis and application of PDTeSn prove that they are promising cathode materials for rechargeable lithium batteries.