Transition metal dichalcogenides (TMDs) have been widely studied as a promising sulfur host material in Li-S batteries due to their unique physical and chemical properties. Great efforts have been made to prepare carbon/TMDs, especially graphene/TMDs heterostructures as the cathodes of Li-S batteries. Recently, ReS 2 shows a new 1T′ phase and great potential in Li-S batteries because of its stable structure and a large amount of catalytic active sites. Herein, we prepared a new ReS 2 nanosheets anchored on rGO (rGO/1T′-ReS 2 ) composite as a lithium polysulfides (LiPSs) immobilizer and electrocatalyst for Li-S batteries. The unique pore structure and rGO incorporation can effectively mitigate volume expansion and enhance electronical conductivity. Moreover, the novel 1T′ phase of ReS 2 shows both efficient chemical adsorption function and large electrocatalytic active sites of LiPSs . These advantages have been demonstrated by both characterization techniques and theoretical calculations. As a result, the rGO/1T′-ReS 2 /S nanosheets display significantly enhanced coulombic efficiency, rate performance and cycling stability compared with the rGO/S nanosheets and the rGO/1T′-ReS 2 /S nanospheres.
Improving the electrochemical kinetics and the intrinsic poor conductivity of transition metal dichalcogenide (TMD) electrodes is meaningful for developing next-generation energy storage systems. As one of the most promising TMD anode materials, ReS2 shows attractive performance in potassium-ion batteries (PIBs). To overcome the poor kinetic ion diffusion and limited cycling stability of the ReS2-based electrode, herein, the interlayer distance expanding strategy was employed, and reduced graphene oxide (rGO) was introduced into ReS2. Few-layered ReS2 nanosheets were grown on the surface of the rGO with expanded interlayer distance. The prepared ReS2 nanosheets show an expanded distance (∼0.77 nm). The synthesized EI-ReS2@rGO composites were used in PIBs as anode materials. The K-ion storage mechanism of the ReS2-based anode was investigated by in situ X-ray diffraction (XRD) technology, which shows the intercalation and conversion types. The EI-ReS2@rGO nanocomposites show high specific capacities of 432.5, 316.5, and 241 mAh g–1 under 0.05, 0.2, and 1.0 A g–1 current densities and exhibit excellent reversibility at 1.0 A g–1. Overall, this strategy, which finely tunes the local chemistry and orbital hybridization for high-performance PIBs, will open up a new field for other materials.
Nan Wei,Jingsheng Cai,Ruochen Wang,Menglei Wang,Wei Lv,Haina Ci,Jingyu Sun,Zhongfan Liu
Lithium–sulfur battery is amongst the most promising next-generation energy storage technology owing to their high theoretical capacity and energy density . Nevertheless, the notorious shuttle effect of lithium polysulfides (LiPSs) seriously impedes its practical applications. Here, we report an all-CVD approach to realize the direct growth of ReS 2 @N-doped graphene (NG) heterostructure , which serves as an ultralight high-performance interlayer for elevated LiPS regulation via easy transfer onto the commercial separator. In contrast to the traditional interlayers constructed via vacuum filtration of nanostructured materials that inevitably increase the thickness and weight of the separator, our all-CVD-enabled ReS 2 @NG film possesses an area of 15 mm × 100 mm, a thickness of ~0.5 μm and a negligible areal weight of 80–90 μg cm −2 . Benefiting from the two-dimensional (2D) vertically-erected nanostructure , adsorptive ReS 2 -conductive NG interface, and favorable electrical conductivity , thus-derived ReS 2 @NG interlayer readily enhances reaction kinetics for LiPS conversion and boosts the reutilization of trapped LiPS whilst guaranteeing smooth transportation of lithium ions . Accordingly, an initial discharge capacity of 854 mAh g −1 with an average capacity decay of 0.064% per cycle after 800 cycles can be harvested at 2.0 C. Even at a high sulfur loading of 6.4 mg cm −2 , an initial areal capacity of 6.1 mAh cm −2 can be gained, which still retains 5.8 mAh cm −2 after 40 cycles at 0.1 C. This work is anticipated to shed light upon the construction of CVD-enabled versatile 2D heterostructures for enriching the interlayer design with multifunctionality and cost-effectiveness.
危险品化学品经营许可证（带存储）