The shuttling diffusion of polysulfides is a bottleneck that seriously limits the performance of Li-S batteries.Purposeful construction of sulfur cathodes with reliable trapping ability of polysulfides is the key to o...The shuttling diffusion of polysulfides is a bottleneck that seriously limits the performance of Li-S batteries.Purposeful construction of sulfur cathodes with reliable trapping ability of polysulfides is the key to overcome such limitation.Herein,a hierarchical porous architecture,i.e.,Co(OH)_(2)sheets bonded Ti_3C_(2)T_x MXene aerogel(Co(OH)_(2)/MXA),is constructed via a facile selfassembled approach and used as an efficient free-standing polysulfides reservoir.The interconnected three-dimensional(3D)porous network with void space and strong interfacial interaction not only enables high sulfur loading but facilitates fast ion and electron transport.Experimental and theoretical results confirm the hetero-framework exhibits outstanding immobilization and conversion ability for polysulfides due to its polar surface and bifunctional catalytic activities toward both formation and decomposition of Li2S.The optimized Co(OH)_(2)/MXA cathode delivers excellent rate capability(407 mAh·g^(-1)at 5C)with a sulfur loading of 2.7 mg·cm^(-2),and ultra-stable cycling performance as an extremely small capacity decay of~0.005%per cycle within 1700 cycles at 1C is achieved with a high sulfur loading of 6.7 mg·cm^(-2).More significantly,our design structural/componential methodology here promises the MXene-based aerogel electrodes for LiS batteries and beyond.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.52072151,52171211,52102253,52271218 and U22A20145)Jinan Independent Innovative Team(No.2020GXRC015)+1 种基金the Major Program of Shandong Province Natural Science Foundation(No.ZR2021ZD05)the Science and Technology Program of University of Jinan(Nos.XKY2119 and XKY2304)。
文摘The shuttling diffusion of polysulfides is a bottleneck that seriously limits the performance of Li-S batteries.Purposeful construction of sulfur cathodes with reliable trapping ability of polysulfides is the key to overcome such limitation.Herein,a hierarchical porous architecture,i.e.,Co(OH)_(2)sheets bonded Ti_3C_(2)T_x MXene aerogel(Co(OH)_(2)/MXA),is constructed via a facile selfassembled approach and used as an efficient free-standing polysulfides reservoir.The interconnected three-dimensional(3D)porous network with void space and strong interfacial interaction not only enables high sulfur loading but facilitates fast ion and electron transport.Experimental and theoretical results confirm the hetero-framework exhibits outstanding immobilization and conversion ability for polysulfides due to its polar surface and bifunctional catalytic activities toward both formation and decomposition of Li2S.The optimized Co(OH)_(2)/MXA cathode delivers excellent rate capability(407 mAh·g^(-1)at 5C)with a sulfur loading of 2.7 mg·cm^(-2),and ultra-stable cycling performance as an extremely small capacity decay of~0.005%per cycle within 1700 cycles at 1C is achieved with a high sulfur loading of 6.7 mg·cm^(-2).More significantly,our design structural/componential methodology here promises the MXene-based aerogel electrodes for LiS batteries and beyond.
