TY  - JOUR
A1  - Yan, Runyu
A1  - Oschatz, Martin
A1  - Wu, Feixiang
T1  - Towards stable lithium-sulfur battery cathodes by combining physical and chemical confinement of polysulfides in core-shell structured nitrogen-doped carbons
JF  - Carbon
N2  - Despite intensive research on porous carbon materials as hosts for sulfur in lithium-sulfur battery cathodes, it remains a problem to restrain the soluble lithium polysulfide intermediates for a long-term cycling stability without the use of metallic or metal-containing species. Here, we report the synthesis of nitrogen-doped carbon materials with hierarchical pore architecture and a core-shell-type particle design including an ordered mesoporous carbon core and a polar microporous carbon shell. The initial discharge capacity with a sulfur loading up to 72 wt% reaches over 900 mA h g(sulf)(ur)(-1) at a rate of C/2. Cycling performance measured at C/2 indicates similar to 90% capacity retention over 250 cycles. In comparison to other carbon hosts, this architecture not only provides sufficient space for a high sulfur loading induced by the high-pore-volume particle core, but also enables a dual effect of physical and chemical confinement of the polysulfides to stabilize the cycle life by adsorbing the soluble intermediates in the polar microporous shell. This work elucidates a design principle for carbonaceous hosts that is capable to provide simultaneous physical-chemical confinement. This is necessary to overcome the shuttle effect towards stable lithium-sulfur battery cathodes, in the absence of additional membranes or inactive metal-based anchoring materials.
KW  - lithium-sulfur battery
KW  - sulfur
KW  - porous carbon
KW  - cathode
KW  - polysulfides
Y1  - 2020
U6  - https://doi.org/10.1016/j.carbon.2020.01.046
SN  - 0008-6223
SN  - 1873-3891
VL  - 161
SP  - 162
EP  - 168
PB  - Elsevier Science
CY  - Amsterdam [u.a.]
ER  - 
TY  - JOUR
A1  - Xie, Dongjiu
A1  - Jouini, Oumeima
A1  - Mei, Shilin
A1  - Quan, Ting
A1  - Xu, Yaolin
A1  - Kochovski, Zdravko
A1  - Lu, Yan
T1  - Spherical polyelectrolyte brushes templated hollow C@MnO nanospheres as sulfur host materials for Li-S batteries
JF  - ChemNanoMat : Chemistry of Nanomaterials for Energy, Biology and More
N2  - Li-S battery has been considered as the next-generation energy storage device, which still suffers from the shuttle effect of lithium polysulfides (LiPSs). In this work, mesoporous hollow carbon-coated MnO nanospheres (C@MnO) have been designed and synthesized using spherical polyelectrolyte brushes (SPB) as template, KMnO4 as MnO precursor, and polydopamine as carbon source to improve the electrochemical performance of Li-S battery. The hollow C@MnO nanospheres enable the combination of physical confinement and chemical adsorption of the LiPSs. The thin carbon coating layer can provide good electrical conductivity and additional physical confinement to polysulfides. Moreover, the encapsulated MnO inside the carbon shell exhibits strong chemical adsorption to polysulfides. The constructed C@MnO/S cathode shows the discharge capacity of 1026 mAh g(-1) at 0.1 C with 79% capacity retention after 80 cycles. The synthesized hollow C@MnO nanoparticles can work as highly efficient sulfur host materials, providing an effective solution to suppress the shuttle effect in Li-S battery.
KW  - hollow nanospheres
KW  - lithium-sulfur battery
KW  - manganese monoxide
KW  - sperical
KW  - polyelectrolyte brushes
Y1  - 2022
U6  - https://doi.org/10.1002/cnma.202100455
SN  - 2199-692X
VL  - 8
IS  - 4
PB  - Wiley-VCH
CY  - Weinheim
ER  -