过渡金属硫化物改性锂硫电池正极材料
Transition-Metal Sulfides Modified Cathode of Li-S Batteries
锂硫电池(LSBs)由于单质硫正极具有超高能量密度(2600 Wh/kg)和超高理论比容量(1675 mAh/g),且环境友好、成本低廉,被认为是最有前景的储能体系之一。然而,硫正极的绝缘性和严重体积膨胀以及多硫化物(LiPSs)的“穿梭效应”等问题导致活性物质利用率低、循环稳定性差及电化学反应动力不足,严重阻碍了LSBs的商业化发展。最新研究表明,过渡金属硫化物作为载体或添加剂能够显著改善LSBs正极材料的电化学性能。本文从等效/共正极作用、导电性增强作用、LiPSs吸附作用和电化学反应催化作用四个方面梳理了过渡金属硫化物在LSBs正极材料中的改性机理,并指出多元过渡金属硫化物复合﹑纳米结晶和量子化作为增加比表面积和活性位点的方法是过渡金属硫化物用于锂硫电池正极材料的重要发展方向,可大幅提升LSBs的电化学性能。
Lithium-sulfur batteries(LSBs) are considered as one of the most promising energy storage systems due to the ultra-high theoretical energy density(2600 Wh/kg) and ultra-high theoretical specific capacity(1675 mAh/g), environmental friendliness and low-cost of sulfur cathode. However, the insulation of sulfur cathode, the volumetric strain and the “shuttle effect” of polysulfides lead to problems such as low utilization rate of active materials, poor cycle stability and low redox kinetics, which seriously hinder the commercial development of LSBs. Recent studies have shown that transition metal sulfides as host or additives can significantly improve the electrochemical performance of LSBs cathode materials. In this paper, the modification mechanism of transition metal sulfides in LSBs cathode materials is reviewed from four aspects: equivalent/common positive electrode effect, conductivity enhancement, LiPSs adsorption and electrochemical reaction catalysis. It is pointed out that multi-transition metal sulfides composite, nano-crystallization and quantization as important areas for increasing the specific surface area and active sites should be used as transition metal sulfides for lithium-sulfur battery cathode materials, which can greatly improving the electrochemical performance of LSBs.
锂硫电池 / 过渡金属硫化物 / 电化学性能 / 穿梭效应 / 吸附作用 / 催化作用 {{custom_keyword}} /
lithium sulfur batteries / transition-metal sulfides / electrochemical performance / shuttle effect / adsorption / catalysis {{custom_keyword}} /
图2 MoSx作为LSBs硫等效材料的电化学性能:(a)MoS2等效正极充放电曲线,(b)“激活”后MoS2等效正极充放电曲线,(c,d) MoS3等效正极电化学性能曲线[34]Fig. 2 Electrochemical performance of MoSx as a sulfur equivalent material for LSBs:(a)MoS2 equivalent positive charge and discharge curve,(b)MoS2 equivalent positive charge and discharge curve after “activation”,(c,d) MoS3 equivalent positive electrode electrochemical performance curves[34] |
TMSs | Conductivity(S/cm) | ref |
---|---|---|
FeS | 80 | 36 |
Ni3S2 | 1.8×10-5 | 49 |
Co9S8 | 2.9×102 | 46 |
CuS | 8.7×102 | 49 |
CoS2 | 6.7×103 | 33 |
Graphene | 106 | 50 |
Graphene oxide | 1.7×102 | 50 |
MoS2 | 3.1 | 47 |
Fe3O4 | 4.0×10-3 | 51 |
NiO | 10-13 | 55 |
V2O5 | 3.7×10-2 | 45 |
TiO2 | 10-10 | 17 |
CoO | 2.0×10-4 | 33 |
Ti4O7 | 3.2 | 48 |
MnO2 | 10-5 | 48 |
WS2 | 6.7 | 52 |
TiS2 | 30~50 | 53 |
VS2 | 0.1 | 17 |
FeS2 | 0.6 | 54 |
Graphite | 1~1000 | 33 |
表2 过渡金属硫化物对LiPSs结合能表Table 2 Binding energy of transition-metal sulfides to LiPSs |
TMSs | Crystal face | LiPSs | Binding energy(eV) | ref |
---|---|---|---|---|
Co9S8 | (002) | Li2S2 | 2.22 | 35 |
(202) | 3.29 | |||
(008) | 6.06 | |||
Co3S4 | (111) | Li2S4 | 2.26 | 33 |
Li2S6 | 1.61 | |||
Li2S8 | 1.68 | |||
(220) | Li2S4 | 2.76 | ||
Li2S6 | 2.18 | |||
Li2S8 | 2.18 | |||
CoS2 | (111) | Li2S4 | 1.97 | 64 |
Li2S6 | 1.01 | |||
TiS2 | Li2S | 2.99 | ||
Li2S6 | 1.02 | |||
MoS2 | Li2S2 | 0.82 | 43 | |
NbS2 | Li2S2 | 0.76 | ||
FeS | Li2S6 | 0.87 | 60, 57 | |
SnS2 | Li2S6 | 0.80 | 62 | |
VS2 | Li2S6 | 1.04 | 62 | |
NiS2 | (111) | Li2S4 | 2.06 | 35 |
Ni3S2 | Li2S6 | 0.72 | 60 | |
WS2 | S8 | 0.30 | 27 | |
Li2S8 | 0.52 | |||
Li2S6 | 0.85 | |||
Li2S4 | 0.80 | |||
Li2S2 | 1.05 | |||
Li2S | 1.45 | |||
ZrS2 | Li2S2 | 2.70 | 59 | |
TiO2 | Li2S | 1.66 | ||
Graphene | Li2S4 | 0.34 | 35 | |
Graphite | Li2S | 0.60 |
图7 金属硫化物对LiPSs的吸附能:(a)Ni3S2对不同LiPSs吸附能的吸附能,(b)不同金属硫化物对不同类型LiPSs吸附能,(c)不同晶面结构硫化物对LiPSs吸附能[35,63]Fig. 7 Adsorption energy of transition metal sulfides to LiPSs:(a)Adsorption energy of Ni3S2 for adsorption energy of different LiPSs,(b)Adsorption energy of different metal sulfides for different types of LiPSs,(c)Adsorption energy of LiPSs by sulfides of different crystal plane structures[35,63] |
图11 各种金属硫化物表面的锂离子扩散特性及机理分析:(a)氧化过程CV峰值电流与扫描速率的平方根,(b)各种金属硫化物扩散过程的能量分布,(c)不同复合电极在0.5 C下300次循环的循环性能和库仑效率[62]Fig. 11 Lithium ion diffusion properties on the surface of various metal sulfides with mechanism analysis:(a)oxidation process versus the square root of the scan rates,(b)energy profiles for diffusion processes of Li ion on Ni3S2, SnS2, FeS, CoS2, VS2, TiS2, and graphene and(c)cycling performance and coulombic efficiency of the different composite electrodes at 0.5 C for 300 cycles[62] |
表3 TMSs作为LSBs不同组件的数据报告Table 3 Data report of TMSs as different components in LSBs |
TMSs | Initial capacity (mAh·g-1) | Sulfur loading (mg·cm-2) | ref |
---|---|---|---|
CoS2 interlayer | 1240 at 0.2 C | 1.55 | 70 |
CoS2 additive | 1326 at 0.1 C | 2.3 | 33 |
Co9S8 host | 1130 at 0.05 C | 1.5 | 37 |
Co9S8-Celgard | 1385 at 0.1 C | 2.0 | 71 |
TiS2 additive | 1000 at 0.1 C | N/A | 22 |
TiS2 encapsulation | 1156 at 0.2 C | 2 | 17 |
MoS2 additive | 1270 at 0.2 C | 2 | 72 |
MoS2 coating | 950 at 0.2 C | N/A | 73 |
NiS2 additive | 1203 at 0.1 C | 2.0~3.3 | 25 |
WS2 host | 1581 at 0.1 C | 2 | 28 |
WS2 interlayer | 1454 at 0.02 C | 4 | 74 |
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The Li-S battery has been under intense scrutiny for over two decades, as it offers the possibility of high gravimetric capacities and theoretical energy densities ranging up to a factor of five beyond conventional Li-ion systems. Herein, we report the feasibility to approach such capacities by creating highly ordered interwoven composites. The conductive mesoporous carbon framework precisely constrains sulphur nanofiller growth within its channels and generates essential electrical contact to the insulating sulphur. The structure provides access to Li+ ingress/egress for reactivity with the sulphur, and we speculate that the kinetic inhibition to diffusion within the framework and the sorption properties of the carbon aid in trapping the polysulphides formed during redox. Polymer modification of the carbon surface further provides a chemical gradient that retards diffusion of these large anions out of the electrode, thus facilitating more complete reaction. Reversible capacities up to 1,320 mA h g(-1) are attained. The assembly process is simple and broadly applicable, conceptually providing new opportunities for materials scientists for tailored design that can be extended to many different electrode materials. {{custom_citation.content}}
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Porous graphitic carbon of high specific surface area of 1416 m(2) g(-1) and high pore volume of 1.11 cm(3) g(-1) is prepared by using commercial CaCO3 nanoparticles as template and sucrose as carbon source followed by 1200 °C high-temperature calcination. Sulfur/porous graphitic carbon composites with ultra high sulfur loading of 88.9 wt % (88.9%S/PC) and lower sulfur loading of 60.8 wt % (60.8%S/PC) are both synthesized by a simple melt-diffusion strategy, and served as cathode of rechargeable lithium-sulfur batteries. In comparison with the 60.8%S/PC, the 88.9%S/PC exhibits higher overall discharge capacity of 649.4 mAh g(-1)(S-C), higher capacity retention of 84.6% and better coulombic efficiency of 97.4% after 50 cycles at a rate of 0.1C, which benefits from its remarkable specific capacity with such a high sulfur loading. Moreover, by using BP2000 to replace the conventional acetylene black conductive agent, the 88.9% S/PC can further improve its overall discharge capacity and high rate property. At a high rate of 4C, it can still deliver an overall discharge capacity of 387.2 mAh g(-1)(S-C). The porous structure, high specific surface area, high pore volume and high electronic conductivity that is originated from increased graphitization of the porous graphitic carbon can provide stable electronic and ionic transfer channel for sulfur/porous graphitic carbon composite with ultra high sulfur loading, and are ascribed to the excellent electrochemical performance of the 88.9%S/PC. {{custom_citation.content}}
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A tube-in-tube carbon nanostructure (TTCN) with multi-walled carbon nanotubes (MWNTs) confined within hollow porous carbon nanotubes is synthesized for Li-S batteries. The structure is designed to enhance the electrical conductivity, hamper the dissolution of lithium polysulfide, and provide large pore volume for sulfur impregnation. As a cathode material for Li-S batteries, the S-TTCN composite with 71 wt% sulfur content delivers high reversible capacity, good cycling performance as well as excellent rate capabilities. {{custom_citation.content}}
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Fully lithiated lithium sulphide (Li2S) is currently being explored as a promising cathode material for emerging energy storage applications. Like their sulphur counterparts, Li2S cathodes require effective encapsulation to reduce the dissolution of intermediate lithium polysulphide (Li2Sn, n=4-8) species into the electrolyte. Here we report, the encapsulation of Li2S cathodes using two-dimensional layered transition metal disulphides that possess a combination of high conductivity and strong binding with Li2S/Li2Sn species. In particular, using titanium disulphide as an encapsulation material, we demonstrate a high specific capacity of 503 mAh g(-1)(Li2S) under high C-rate conditions (4C) as well as high areal capacity of 3.0 mAh cm(-2) under high mass-loading conditions (5.3 mg(Li2S) cm(-2)). This work opens up the new prospect of using transition metal disulphides instead of conventional carbon-based materials for effective encapsulation of high-capacity electrode materials. {{custom_citation.content}}
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<![CDATA[Increasing demands for lithium-ion batteries (LIBs) with high energy density and high power density require highly reversible electrochemical reactions to enhance the cyclability and capacities of electrodes. As the reversible formation/decomposition of the solid electrolyte interface (SEI) film during the lithiation/delithiation process of Fe3S4 could bring about a higher capacity than its theoretical value, in the present work, synthesized Fe3S4 nanoparticles are sandwich-wrapped with reduced graphene oxide (RGO) to fabricate highly reversible and long cycling life anode materials for high-performance LIBs. The micron-sized long slit between sandwiched RGO sheets effectively prevents the aggregation of intermediate phases during the discharge/charge process and thus increases cycling capacity because of the reversible formation/decomposition of the SEI film driven by Fe nanoparticles. Furthermore, the RGO sheets interconnect with each other by a face-to-face mode to construct a more efficiently conductive network, and the maximum interfacial oxygen bridge bonds benefit the fast electron hopping from RGO to Fe3S4, improving the depth of the electrochemical reactions and facilitating the highly reversible lithiation/delithiation of Fe3S4. Thus, the resultant Fe3S4/RGO hybrid shows a highly reversible charge capacity of 1324 mA h g-1 over 275 cycles at a current density of 100 mA g-1, even retains 480 mA h g-1 over 500 cycles at 1000 mA g-1, which are much higher than reported values.]]> {{custom_citation.content}}
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<![CDATA[S/NiS2-C composites were fabricated using a sample melting-diffusing-reacting strategy. When the elemental sulfur content in the composite is 54.9 wt%, it shows good cyclic performance and delivers a specific capacity of 730 mA h g-1 after 200 cycles at 0.5 C and 544 mA h g-1 after 500 cycles at 2 C. The elemental sulfur content can be adjusted, and when the elemental sulfur content is increased to 64.8 wt% and 76.0 wt%, the cathodes can maintain a stable cyclic capacity of 386 and 312 mA h g-1 after being discharged/charged at 2 C for 500 cycles respectively. The carbon structure and the uniformly distributed nickel disulfide in the S/NiS2-C composites efficiently stabilizes the polysulfides and also facilitates the conversion of electrochemical reactions.]]> {{custom_citation.content}}
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<![CDATA[Conductive metal sulfides are promising multi-functional additives for future lithium-sulfur (Li-S) batteries. These can increase the sulfur cathode's electrical conductivity to improve the battery's power capability, as well as contribute to the overall cell-discharge capacity. This multi-functional electrode design showed initial promise; however, complicated interactions at the system level are accompanied by some detrimental side effects. The metal sulfide additives with a chemical conversion as the reaction mechanism, e.g., CuS and FeS2, can increase the theoretical capacity of the Li-S system. However, these additives may cause undesired parasitic reactions, such as the dissolution of the additive in the electrolyte. Studying such complex reactions presents a challenge because it requires experimental methods that can track the chemical and structural evolution of the system during an electrochemical process. To address the fundamental mechanisms in these systems, we employed an operando multimodal x-ray characterization approach to study the structural and chemical evolution of the metal sulfide-utilizing powder diffraction and fluorescence imaging to resolve the former and absorption spectroscopy the latter-during lithiation and de-lithiation of a Li-S battery with CuS as the multi-functional cathode additive. The resulting elucidation of the structural and chemical evolution of the system leads to a new description of the reaction mechanism.]]> {{custom_citation.content}}
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Lithium-sulfur (Li-S) battery system is endowed with tremendous energy density, resulting from the complex sulfur electrochemistry involving multielectron redox reactions and phase transformations. Originated from the slow redox kinetics of polysulfide intermediates, the flood of polysulfides in the batteries during cycling induced low sulfur utilization, severe polarization, low energy efficiency, deteriorated polysulfide shuttle, and short cycling life. Herein, sulfiphilic cobalt disulfide (CoS2) was incorporated into carbon/sulfur cathodes, introducing strong interaction between lithium polysulfides and CoS2 under working conditions. The interfaces between CoS2 and electrolyte served as strong adsorption and activation sites for polar polysulfides and therefore accelerated redox reactions of polysulfides. The high polysulfide reactivity not only guaranteed effective polarization mitigation and promoted energy efficiency by 10% but also promised high discharge capacity and stable cycling performance during 2000 cycles. A slow capacity decay rate of 0.034%/cycle at 2.0 C and a high initial capacity of 1368 mAh g(-1) at 0.5 C were achieved. Since the propelling redox reaction is not limited to Li-S system, we foresee the reported strategy herein can be applied in other high-power devices through the systems with controllable redox reactions. {{custom_citation.content}}
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<![CDATA[Lithium-sulfur (Li-S) chemistry is projected to be one of the most promising for next-generation battery technology, and controlling the inherent "polysulfide shuttle" process has become a key research topic in the field. Regulating intermediary polysulfide dissolution by understanding the metamorphosis is essential for realizing stable and high-energy-density Li-S batteries. As of yet, a clear consensus on the basic surface/interfacial properties of the sulfur electrode has not been achieved, although the catalytic phenomenon has been shown to result in enhanced cell stability. Herein, we present evidence that the polysulfide shuttle in a Li-S battery can be stabilized by using electrocatalytic transition metal dichalcogenides (TMDs). Physicochemical transformations at the electrode/electrolyte interface of atomically thin monolayer/few-layer TMDs were elucidated using a combination of spectroscopic and microscopic analysis techniques. Preferential adsorption of higher order liquid polysulfides and subsequent conversion to lower order solid species in the form of dendrite-like structures on the edge sites of TMDs have been demonstrated. Further, detailed electrochemical properties such as activation energy, exchange current density, rate capabilities, cycle life, etc. have been investigated by synthesizing catalytically active nanostructured TMDs in bulk quantity using a liquid-based shear-exfoliation method. Unveiling a specific capacity of 590 mAh g-1 at 0.5 C rate and stability over 350 cycles clearly indicates yet another promising application of two-dimensional TMDs.]]> {{custom_citation.content}}
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Exploring the chemical reactivity of different atomic sites on crystal surface and controlling their exposures are important for catalysis and renewable energy storage. Here, we use two-dimensional layered molybdenum disulfide (MoS2) to demonstrate the electrochemical selectivity of edge versus terrace sites for Li-S batteries and hydrogen evolution reaction (HER). Lithium sulfide (Li2S) nanoparticles decorates along the edges of the MoS2 nanosheet versus terrace, confirming the strong binding energies between Li2S and the edge sites and guiding the improved electrode design for Li-S batteries. We also provided clear comparison of HER activity between edge and terrace sites of MoS2 beyond the previous theoretical prediction and experimental proof. {{custom_citation.content}}
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The lithium-sulphur battery relies on the reversible conversion between sulphur and Li2S and is highly appealing for energy storage owing to its low cost and high energy density. Porous carbons are typically used as sulfur hosts, but they do not adsorb the hydrophilic polysulphide intermediates or adhere well to Li2S, resulting in pronounced capacity fading. Here we report a different strategy based on an inherently polar, high surface area metallic oxide cathode host and show that it mitigates polysulphide dissolution by forming an excellent interface with Li2S. Complementary physical and electrochemical probes demonstrate strong polysulphide/Li2S binding with this 'sulphiphilic' host and provide experimental evidence for surface-mediated redox chemistry. In a lithium-sulphur cell, Ti4O7/S cathodes provide a discharge capacity of 1,070 mAh g(-1) at intermediate rates and a doubling in capacity retention with respect to a typical conductive carbon electrode, at practical sulphur mass fractions up to 70 wt%. Stable cycling performance is demonstrated at high rates over 500 cycles. {{custom_citation.content}}
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We demonstrated revertible shifts of surface-dependent localized surface plasmon resonances (LSPRs) in CuS nanodisks. Oleylamine (OYA) served as a solvent and surface ligand covering on CuS nanodisks during the thermolysis of single-source precursor copper ethylxanthate (Cu(ex)2). When OYA ligand was unloaded and reloaded on the surface of CuS nanodisks, the wavelength of LSPRs blue-shifted due to more oxygen exposure and then reverted through surface repassivation. The surface-dependent shift of LSPRs was dominated by the concentration of free holes in CuS nanodisks, which was modulated by the coverage and exchange of surface ligands, and the oxygen exposure dose and time. The semiconductor nanocrystals with tunable LSPRs have great potential in advanced plasmonics. {{custom_citation.content}}
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[59] |
Trapping lithium polysulfides formed in the sulfur positive electrode of lithium-sulfur batteries is one of the promising approaches to overcome the issues related to polysulfide dissolution. In this work, we demonstrate that intrinsically hydrophilic magnesium oxide (MgO) nanoparticles having surface hydroxyl groups can be used as effective additives to trap lithium polysulfides in the positive electrode. MgO nanoparticles were uniformly distributed on the surface of the active sulfur, and the addition of MgO into the sulfur electrode resulted in an increase in capacity retention of the lithium-sulfur cell compared to a cell with pristine sulfur electrode. The improvement in cycling stability was attributed to the strong chemical interactions between MgO and lithium polysulfide species, which suppressed the shuttling effect of lithium polysulfides and enhanced the utilization of the sulfur active material. To the best of our knowledge, this report is the first demonstration of MgO as an effective functional additive to trap lithium polysulfides in lithium-sulfur cells. {{custom_citation.content}}
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[60] |
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[61] |
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[62] |
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[63] |
<![CDATA[Lithium-sulfur (Li-S) batteries have attracted interest as a promising energy-storage technology due to their overwhelming advantages such as high energy density and low cost. However, their commercial success is impeded by deterioration of sulfur utilization, significant capacity fade, and poor cycle life, which are principally originated from the severe shuttle effect in relation to the dissolution and migration of lithium polysulfides. Herein, we proposed an effective and facile strategy to anchor the polysulfides and improve sulfur loading by constructing a three-dimensionally hierarchical Ni/Ni3S2/S cathode. This self-supported hybrid architecture is sequentially fabricated by the partial sulfurization of Ni foam by a mild hydrothermal process, followed by physical loading of elemental sulfur. The incorporation of Ni3S2, with high electronic conductivity and strong polysulfide adsorption capability, can not only empower the cathode to alleviate the shuttle effect, but also afford a favorable electrochemical environment with lower interfacial resistance, which could facilitate the redox kinetics of the anchored polysulfides. Consequently, the obtained Ni/Ni3S2/S cathode with a sulfur loading of ∼4.0 mg/cm2 demonstrated excellent electrochemical characteristics. For example, at high current density of 4 mA/cm2, this thick cathode demonstrated a discharge capacity of 441 mAh/g at the 150th cycle.]]> {{custom_citation.content}}
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[64] |
<![CDATA[Lithium-sulfur (Li-S) battery has emerged as one of the most promising next-generation energy-storage systems. However, the shuttle effect greatly reduces the battery cycle life and sulfur utilization, which is great deterrent to its practical use. This paper reviews the tremendous efforts that are made to find a remedy for this problem, mostly through physical or chemical confinement of the lithium polysulfides (LiPSs). Intrinsically, this "confinement" has a relatively limited effect on improving the battery performance because in most cases, the LiPSs are "passively" blocked and cannot be reused. Thus, this strategy becomes less effective with a high sulfur loading and ultralong cycling. A more "positive" method that not only traps but also increases the subsequent conversion of LiPSs back to lithium sulfides is urgently needed to fundamentally solve the shuttle effect. Here, recent advances on catalytic effects in increasing the rate of conversion of soluble long-chain LiPSs to insoluble short-chain Li2S2/Li2S, and vice versa, are reviewed, and the roles of noble metals, metal oxides, metal sulfides, metal nitrides, and some metal-free materials in this process are highlighted. Challenges and potential solutions for the design of catalytic cathodes and interlayers in Li-S battery are discussed in detail.]]> {{custom_citation.content}}
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[65] |
韩东梅(Han D M), 王拴紧(Wang S J), 沈培康(Shen P K), 孟跃中(Meng Y Z), . 电池( Battery Bimonthly), 2013,43(1):6.
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[66] |
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[67] |
A space-confined "sauna" reaction system is introduced for the simultaneous reduction and functionalization of graphene oxide to unique graphene-sulfur hybrid nanosheets, in which thin layers of amorphous sulfur are tightly anchored on the graphene sheet via strong chemical bonding. Upon being used as the cathode material in lithium-sulfur batteries, the as-synthesized composite shows an excellent electrochemical performance. {{custom_citation.content}}
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[68] |
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[69] |
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[70] |
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[71] |
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[72] |
The practical implementation of Li-S technology has been hindered by short cycle life and poor rate capability owing to deleterious effects resulting from the varied solubilities of different Li polysulfide redox products. Here, we report the preparation and utilization of composites with a sulfur-rich matrix and molybdenum disulfide (MoS2) particulate inclusions as Li-S cathode materials with the capability to mitigate the dissolution of the Li polysulfide redox products via the MoS2 inclusions acting as "polysulfide anchors". In situ composite formation was completed via a facile, one-pot method with commercially available starting materials. The composites were afforded by first dispersing MoS2 directly in liquid elemental sulfur (S8) with sequential polymerization of the sulfur phase via thermal ring opening polymerization or copolymerization via inverse vulcanization. For the practical utility of this system to be highlighted, it was demonstrated that the composite formation methodology was amenable to larger scale processes with composites easily prepared in 100 g batches. Cathodes fabricated with the high sulfur content composites as the active material afforded Li-S cells that exhibited extended cycle lifetimes of up to 1000 cycles with low capacity decay (0.07% per cycle) and demonstrated exceptional rate capability with the delivery of reversible capacity up to 500 mAh/g at 5 C. {{custom_citation.content}}
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[73] |
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[74] |
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