Facile synthesis of Co3−xMnxO4/C nanocages as an efficient sulfur host for lithium–sulfur batteries with enhanced rate performance

Self Cite

In consideration of the inferior rate performance and low sulfur utilization of lithium–sulfur batteries (LSBs), an effective strategy via combining polar materials with the conductive carbon sulfur host is widely applied. Herein, metal organic framework-derived in situ-developed ZnIn2S4@C is innovatively synthesized to mediate lithium polysulfide (LPS) conversion based on high electron conductivity and strong chemical interactions for advanced LSBs. Polar ZnIn2S4 possesses strong chemisorption in keeping with the DFT calculation results and catalytic for LPSs, ensuring a high sulfur utilization. Meanwhile, the hollow non-polar carbon frame possessing hierarchical pores not only provides internal space to contain active species but also accommodates efficient electronic transferring and diffusion of lithium ions in the process of cycling. The above advantages make the electrode possess promising stability and good rate performances, achieving long-term and high-rate cycling. Thus, under a sulfur loading of 1.5 mg cm–2, after 500 cycles, at 2 and 5 C, the as-prepared ZnIn2S4@C@S delivers reversible capacities of 734 mA h g–1 (75.7% of the initial capacity with a dropping rate of 0.015% per cycle) and 504 mA h g–1 (68.5% of the primal capacity with a dropping rate of 0.029% per cycle), respectively. Even at a high sulfur loading of 5.0 mg cm–2, at 5 C, 65.6% of the initial capacity can be maintained with a low fading rate of 0.430% per cycle after 500 loops with a high Coulombic efficiency of around 99.8%.

Section: Introductionmentioning

confidence: 99%

Reasonably Introduced ZnIn₂S₄@C to Mediate Polysulfide Redox for Long-Life Lithium–Sulfur Batteries

Zhang

Luo

Zhou

et al. 2021

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“…In the high-resolution spectroscopy In 3d spectra of In 2 O 3 @C (Figure d), two dominant peaks at about 445.0 and 452.5 eV correspond to In 3d 5/2 and In 3d 3/2 of In 3+ , respectively, meaning that there is no formation of In metal under the carbonization process. The C 1 s spectra of In 2 O 3 @C (Figure e) are deconvoluted into three bonding energies, associated with C–C (284.8 eV), C–O (286.5 eV), and CC (289.8 eV) . In the overall XPS spectrum (Figure S7a), the peaks of carbon in In 2 O 3 @C are significantly higher than those in In 2 O 3 , indicating the existence of a carbon layer in In 2 O 3 @C. In Figure S7b,c, the spectral comparison of In 3d and 1s between In 2 O 3 and In 2 O 3 @C showed that both peaks of In2O3@C move to a higher binding energy of about 1.1 eV, which may be caused by the carbon layer increasing the oxygen defects in the material.…”

Section: Resultsmentioning

confidence: 99%

Nanorod In₂O₃@C Modified Separator with Improved Adsorption and Catalytic Conversion of Soluble Polysulfides for High-Performance Lithium–Sulfur Batteries

Wang,

Shi,

Wang

et al. 2024

The shuttle effect of soluble lithium polysulfides (LiPSs) poses a crucial challenge for commercializing lithium− sulfur batteries. The functionalization of the separator is an effective strategy for enhancing the cell lifespan through the capture and reuse of LiPSs. Herein, a novel In 2 O 3 nanorod with an ultrathin carbon layer (In 2 O 3 @C) was coated on a polypropylene separator. The results demonstrate the adsorption and catalysis of In 2 O 3 on polysulfides, effectively inhibiting the shuttle effect and improving the redox kinetics of LiPSs. Besides, the ultrathin carbon layer increases the reaction sites and accelerates the electrochemical reaction rate. The cell with the In 2 O 3 @C interlayer displays excellent reversibility and stability with a 0.029% capacity decay each cycle in 2000 cycles at 2C. In addition, the In 2 O 3 @C interlayer significantly improves the cell performance under high current (888.2 mA h g −1 at 2C and room temperature) and low temperature (1007.8 mA h g −1 at 0.1C and −20 °C) conditions.

“…As shown in Figure 4a, the characteristic peaks at 284.8, 286.4, and 288.9 eV represent C−C, C−O, and C�C, respectively. 49 The O 1s XPS spectrum in Figure 4b exhibits that the two typical peaks can be split into three different small peaks, the positions are 529.8 (Metal-O), 531.5 (−OH), and 533.5 eV (CO 2 ). 50,51 In Figure 4c, it can be seen from the Co 2p spectrum that the two dominant peaks with satellite peaks refer to Co 2p 3/2 and Co 2p 1/2 , and each main peak can be deconvoluted into two peaks, in which 780.3 and 795.6 eV correspond to Co 3+ , while 781.2 and 797.1 eV correspond to Co 2+ .…”

Section: Electrochemical Measurementsmentioning

confidence: 99%

A Porous Hexagonal Prism Shaped C-In_2–xCo_xO₃ Electrocatalyst to Expedite Bidirectional Polysulfide Redox in Li–S Batteries

Wang

Zhang

et al. 2022

Self Cite

The shuttling behavior of soluble lithium polysulfides (LPSs) extremely restricts the practical application of lithium sulfur batteries (Li−S batteries). Herein, the hollow porous hexagonal prism shaped C-In 2−x Co x O 3 composite is synthesized to restrain the shuttle effect and accelerate reaction kinetics of LPSs. The novel hexagonal prism porous carbon skeleton not only provides a stable physical framework for sulfur active materials but also facilitates efficient electron transferring and lithium ion diffusion. Meanwhile, the polar In 2−x Co x O 3 is equipped with strong adsorption capacity for LPSs, which is confirmed by density functional theory (DFT) calculations, helping to anchor LPSs. More importantly, the doping of Co regulates the electronic structure environment of In 2 O 3 , expedites the electron transmission, and bidirectionally improves the catalytic conversion ability of LPSs and nucleation− decomposition of Li 2 S. Benefiting from the above advantages, the electrochemical performance of Li−S batteries has been greatly enhanced. Therefore, the C-In 2−x Co x O 3 cathode presents a good rate performance, which exhibits a low-capacity fading rate of 0.052% per cycle over 800 cycles at 5 C. Especially, even under a high sulfur loading of 4.8 mg cm −2 , the initial specific capacity is as high as 903 mAh g −1 , together with a superior capacity retention of 85.6% after 600 cycles at 0.5 C.