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The development of high-efficiency multi-component composite anode nanomaterials for sodium-ion batteries (SIBs) is critical for advancing the further practical application. Numerous multi-component nanomaterials are constructed typically via confinement strategies of surface templating or three-dimensional encapsulation. Herein, a composite of heterostructural multiple sulfides (MoS2/SnS/CoS) well-dispersed on graphene is prepared as an anode nanomaterial for SIBs, via a distinctive lattice confinement effect of a ternary CoMoSn-layered double-hydroxide (CoMoSn-LDH) precursor. Electrochemical testing demonstrates that the composite delivers a high-reversible capacity (627.6 mA h g−1 after 100 cycles at 0.1 A g−1) and high rate capacity of 304.9 mA h g−1 after 1000 cycles at 5.0 A g−1, outperforming those of the counterparts of single-, bi- and mixed sulfides. Furthermore, the enhancement is elucidated experimentally by the dominant capacitive contribution and low charge-transfer resistance. The precursor-based lattice confinement strategy could be effective for constructing uniform composites as anode nanomaterials for electrochemical energy storage. [ABSTRACT FROM AUTHOR]

Abstract: For applications in proton exchange membrane fuel cells at low relative humidity, the composite membranes were prepared with ionic liquids and yttrium oxide (Y2O3). The conductivities of composite membranes were higher than that of the pure SPEEK membrane. The conductivity of composite membranes modified with 1-ethyl-3 methylimidazole tetrafluoroborate (EB) or 1-butyl-3-methylimidazole methanesulfonate (BS) and Y2O3 were 0.08 Sácm-1 and 0.11Sácm-1 at 80¼C, 100% relative humidity(RH) while were 0.07 Sácm-1 and 0.09 Sácm-1 at 80¼C, 50% relative humidity (RH), respectively. The water uptake property would be slightly improved when containing ionic liquids and Y2O3. Compared with pure SPEEK membrane, the thermal stability of composite membranes modified with ionic liquids and Y2O3 was slightly increased by thermal gravimetric analysis, showing the promise for the use at temperatures up to 200¼C. The tensile stresses at break of the composite membranes were respectively 2.61MPa (EB51) and 2.33MPa (BS51) at room temperature. The coordination of ionic liquids and Y2O3 was a good potential method for improving the conductivity at low relative humidity. [Copyright &y& Elsevier]