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Benefiting from the ultrahigh specific surface area, tunable pore size, and abundant surface functionality, biomass derived carbons (BC) are thriving as promising conductive matrices to host sulfur for Li S battery cathodes. Unfortunately, pristine BC still suffers from awful cycling performance rooted in their limited physical/chemical adsorption ability towards polysulfide. Herein, we proposed to construct Nickel Aluminum Layered Double Hydroxides (NiAl-LDH) fences coated on H 3 PO 4 activated BC (PAB) as an efficient sulfur host. The decorated NiAl-LDH fences could efficiently reinforce both chemical adsorption and physical confinement effects on polysulfides, and render as an electrocatalyst to significantly boost the redox reaction kinetics. Furthermore, the DFT simulation has been employed to illustrate enhanced interaction forces towards polysulfides. As a result, the prepared NiAl@PAB/S cell exhibits an improved performance of 1216.3 mAh g−1 initially at 0.2C (1C = 1672 mAh g−1), excellent cycling stability during 300 cycles at 1 C (0.13% decay rate per cycle), and superior rate capability up to 3 C (614.2 mAh g−1). This work provides a cost-efficient and effective method to significantly improve the overall performance of porous-carbon-based Li S battery cathode. [ABSTRACT FROM AUTHOR]

Effectively adsorbing and suppressing the polysulfide shuttle by polar materials are of great importance in lithium-sulfur (Li–S) batteries. Herein, the multifunctional SnS@C MS heterostructure consisting of porous carbon shell and SnS microflower-like core is prepared and demonstrated as an efficient Li–S battery cathode with electrocatalytic activity. The integrated physical confinement, strong chemical interaction, and rapid polysulfides (LiPSs) conversion kinetics are mutually promoted to facilitate a successive LiPSs adsorption-conversion with a significantly suppressed shuttle effect. Notably, systematic investigations and experiments reveal that the porous carbon layer can strongly entrap the LiPSs and subsequently facilitate its conversion kinetics between the liquid and solid phases. As a result, SnS@C/S MS cathode can deliver a high initial capacity of 1074.7 mAh g−1 at 0.1 C and ultra-stable cycling performance with a slow capacity decay rate of 0.073% per cycle over 600 cycles at 0.5 C. Moreover, the excellent durability with higher S loading and current densities are also achieved. Thus, this work proffers a facile and promising approach to design and prepare efficient Li–S battery cathodes with high reversible capacities and excellent cycle performance. [ABSTRACT FROM AUTHOR]

• A novel intercalated-LDH template method to fabricate Co-embedded sulfur host. • Hollow porous microflower-like cathode enables fast electron/ion transport and high sulfur loading. • Synergistic effect of boosted redox kinetics and well-defined physical confinement. The shuttle effect of soluble lithium polysulfides (LiPSs), accompanying with sluggish redox kinetics has severely impeded the implementation of lithium-sulfur (Li-S) batteries. Herein, a novel hollow cobalt-embedded and nitrogen-doped carbonaceous microflower (H-Co-NCM) is fabricated via in situ transformation of metanilic anions intercalated Co-Al layered double hydroxides (CoAl LDHs). The as-obtained S@H-Co-NCM electrode exhibits superior electrocatalytic performances to boost the kinetics of LiPSs conversion and Li 2 S nucleation. Consequently, the assembled Li-S batteries with a high sulfur loading of 82% display a remarkable initial capacity of 1374 mAh g−1 at 0.1 C, excellent rate capability (611 mAh g−1 at 2 C), and superb cycle stability (cyclic decay rate of 0.069% over 500 cycles at 0.5 C). The integrated strategy of strong chemisorption and fast conversion of LiPSs provides deeper insights to suppress the shuttle effect. [ABSTRACT FROM AUTHOR]

• Facile and low-temperature fabrication methods of MOF-derived electrodes. • Hollow zeolitic imidazolate framework-8 (ZIF-8) polyhedron. • Outstanding Li-S battery cycling stability. • Synergetic effect of enhanced confinement and boosted conversion kinetics of LiPSs. Great efforts have been devoted to developing novel cathodes to alleviate the shuttle effect of lithium polysulfides (LiPSs). The limited intrinsic conductivity of metal–organic frameworks (MOFs) compels their utilization as the templates to prepare carbonaceous Li-S battery cathodes after high-temperature treatments. The facile and low-temperature fabrication methods of MOF-derived cathodes are largely unexplored. Herein, the hybrid of hollow zeolitic imidazolate framework-8 (ZIF-8) polyhedron functionalized with carbon nanotube (HZIF/CNT) cathode is fabricated via facile tannic acid (TA) etching and low-temperature treatment. The conductive HZIF/CNT structure with ordered hollow ZIF-8 morphology, rich heteroatoms functionalities, and hydrophilic surface endow strong adsorption of LiPSs, boosted LiPSs conversion kinetics, and regulated Li 2 S deposition. As a result, S@HZIF/CNT cathode delivers a superior initial capacity of 1371 mAh g−1 at 0.1C and excellent rate retention at 3.0C (696 mAh g−1). The remarkable cycling stability is evaluated for 500cycles at 0.5C with a 0.073% capacity decay per cycle. Moreover, the cathode with a high sulfur loading of 3.41 mg cm−2 delivers an initial capacity of 696.4 mAh g−1 at 1.0C and stable cycling performance over 200cycles. This work opens a facile and low-energy route to design advanced sulfur cathodes for high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pioneering application of cyclic phosphate in lithium-sulfur batteries. • Well-defined carbon nanocages with highly dispersed NiCoP 4 O 12 NPs. • Stable adsorption and conversion of polysulfides. • Excellent rate performances up to 5 C and ultralong lifespan over 1500 cycles. Lithium-sulfur batteries (LSBs) are promising next-generation energy storage systems. The construction of high-efficiency electrocatalysts to overcome the barriers of sluggish lithium polysulfides (LiPSs) conversion and shuttle effect is urgent. Herein, nickel–cobalt cyclo-tetraphosphate (NiCoP 4 O 12) nanoparticles embedded in hollow carbon polyhedrons are elaborately prepared and used as excellent polysulfide promoters in LSBs. The well-controlled core–shell structure physically blocks and strongly captures LiPSs, thereby boosting LiPSs conversion kinetics over the large exposed NiCoP 4 O 12 active sites. Meanwhile, the carbon matrix build a conductive network that enables high-speed electron and ion transport, thus forming a rapid and robust "capture-diffusion-transformation" network. As a result, the assembled S@NiCoP 4 O 12 cathode delivers an excellent rate capacity (518.7 mAh g−1 at 5 C), impressive stability (a small capacity decay of 0.0396 % per cycle over 1500 cycles at 1 C), and favorable durability of thick sulfur cathodes under lean electrolyte condition (with 4.13 mg cm−2 sulfur loading and 5.0 µL mg−1 electrolyte) over 120 cycles. [ABSTRACT FROM AUTHOR]

• Develop a facile and controllable pyrolysis strategy to synthesize the NiCo alloys. • A unique heterostructure between NiCo alloy and mixed NiCo-based sulfides were constructed. • The NiCoS coating improves the conductivity of the NiCo-NiCoS@NC nanoparticles. • The NiCo alloy and NiCoS act as trapping-diffusion-conversion sites of polysulfides. • A superior rate capacity of 692 mA h g−1 can be achieved at a high current density of 5 C. The transition-metal-based alloy and chalcogenides have been widely investigated as efficient sulfur host for lithium sulfur batteries (LSB), yet the synergistic effect of both has been rarely reported. Herein, nickel cobalt alloy (NiCo) and nickel cobalt sulfides (NiCoS) have been simultaneously constructed on the nitrogen-doped carbon substrate (NiCo-NiCoS/NC) via facile calcination-sulfurization of NiCo Prussian blue analogue (NiCo-PBA). The abundantly exposed NiCo alloy and NiCoS domains act as adsorption and catalytic sites that enable effective capture and catalytic conversion of polysulfides, and the highly conductive NiCo-NiCoS integrated with N-doped carbon provides a facile Li+ transfer channel. As a result, S@NiCo-NiCoS/NC electrode delivers a high initial discharge capacity of 1345.1 mA h g−1 at the current density of 0.1 C, superior rate capability of 692.1 mA h g−1 up to 5 C, and ultralong lifespan over 1500 cycles with a small capacity decay of 0.055% per cycle at the current density of 1.0 C. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow polyhedral sulfur hosts were constructed using a core–shell dual template. • Multi-phase interfaces boost the LiPSs kinetics. • The In-situ regulation of the surface physiochemistry on hollow substrates. • Excellent electrochemical performance of long lifespan with high sulfur loading. Tailoring well-dispersed nanoparticles on the sulfur host with high catalytic activity is of great importance yet remains challenging in lithium-sulfur batteries (LSBs). Herein, a novel multi-phase interface structure of embedded CoP and Co 2 P nanoparticles (Co x P NPs) on hollow N-doped carbon substance (Co x P/NC) was successfully fabricated by the in-situ conversion of ZIF-67@ZIF-8 dual templates. The abundant multi-phase interfaces on Co x P/NC enabled efficient lithium polysulfides (LiPSs) capture, accelerated Li-ion diffusion, and boosted LiPSs conversion, thus forming a rapid and robust "adsorption-diffusion-conversion" network. Moreover, the well-defined hollow carbon polyhedrons physically inhibit the LiPSs diffusion and provide superior conductivity. As a result, the assembled S@Co x P/NC cathode with a high sulfur loading of 82% delivers an excellent rate capability (617.7 mAh g−1 at 3C), impressive stability (a small capacity decay of 0.053% per cycle over 1250 cycles at 1C), and favorable durability of thick sulfur cathodes (with a high areal sulfur loading of 4.68 mg cm2 over 300 cycles). [ABSTRACT FROM AUTHOR]