Rational design of advanced polar hosts with high sulfur loading, facilitated ionic/electronic transport and effectively suppressed shuttling effect has great potential for high performance lithium-sulfur batteries,ye...
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Rational design of advanced polar hosts with high sulfur loading, facilitated ionic/electronic transport and effectively suppressed shuttling effect has great potential for high performance lithium-sulfur batteries,yet it remains challenging. Here we propose a novel templated spherical coassembly strategy to fabricate the MoS2/C hollow spheres as an efficient sulfur host material. The unique hollow structure provides enough interior space for accommodating a substantial amount of sulfur, and effectively suppresses the diffusion of dissolved polysulfides by both physical confinement and chemical adsorption. Moreover, the ionic transport as well as the ability to mitigate volume variation upon cycling is also improved, thereby maximizing the utilization of sulfur. Owing to these merits, when evaluated as a sulfur host for lithiumsulfur batteries, the MoS2/C hollow spheres exhibit appealing electrochemical performance with an impressive specific capacity of 1082 mA hg-1at 0.1 C, excellent rate capability and superior cycling stability with a low fading rate of 0.04% per cycle.
Potassium-ion capacitors(KICs)are promising for sustainable and eco-friendly energy storage technologies,yet their slow reaction kinetics and poor cyclability induced by large K-ion size are a major obstacle toward pr...
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Potassium-ion capacitors(KICs)are promising for sustainable and eco-friendly energy storage technologies,yet their slow reaction kinetics and poor cyclability induced by large K-ion size are a major obstacle toward practical ***,by employing black phosphorus nanosheets(BPNSs)as a typical high-capacity anode material,we report that BPNS anodes armored with an ultrathin oriented-grown metal–organic-framework(MOF)interphase layer(BPNS@MOF)exhibit regulated potassium storage behavior for highperformance *** MOF interphase layers as protective layer with ordered pores and high chemical/mechanical stability facilitate K ion diffusion and accommodate the volume change of electrode,beneficial for improved reaction kinetics and enhanced cyclability,as evidenced by substantial characterizations,kinetics analysis and DFT ***,the BPNS@MOF electrode as KIC anodes exhibits outstanding cycle performance outperforming most of the reported state-of-art KICs so far.
Dense medium cyclone(DMC)is the working horse in coal *** practice,it is usually operated under constant pressure and the operational conditions(mainly medium-to-coal(M:C)ratio and oper-ational pressure)need to be adj...
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Dense medium cyclone(DMC)is the working horse in coal *** practice,it is usually operated under constant pressure and the operational conditions(mainly medium-to-coal(M:C)ratio and oper-ational pressure)need to be adjusted according to coal washability data(mainly coal particle size and density distributions).Nonetheless,until now it is still not well understood how the M:C ratio would affect the performance of DMCs especially under the practical *** this work,the effect of M:C ratio is for the first time numerically studied under conditions similar to plant operation by using both tra-ditional and coarse-grained(CG)combined approach of computational fluid dynamics(CFD)and discrete element method(DEM),called as traditional CFD-DEM and CG CFD-DEM,in which the flow of coal par-ticles is modelled by DEM or CG DEM which applies Newton's laws of motion to individual particles and that of medium flow by the conventional CFD which solves the local-averaged Navier-Stokes equations,allowing consideration of particle-fluid mutual interaction and particle-particle ***,impulse and momentum connection law is used to achieve energy conservation between traditional CFD-DEM and CG *** is found that under constant pressure,the M:C ratio affects DMC perfor-mance *** specific effect depends on coal washability or coal *** extremely low M:C ratio,the phenomenon that high-quality coal product is misplaced to reject is successfully repro-duced,which has been observed in plants in Australian coal industry and called as"low-density tail".Moreover,strategies are proposed to mitigate the"low-density tail"phenomenon based on the model.
Flexible techniques for producing luminescent patterns with high-resolution and moderate efficiency at the microscale are potentially important for pattern display, customized anti-counterfeiting and data security. An...
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