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A solution-based “hot-injection” approach was developed to synthesize amorphous carbon-decorated and graphene-anchored hollow Co 9 S 8 nanoparticles as anode material for Li ion battery application. Such a rationally designed dually-protected structure could effectively accommodate the volume expansion of Co 9 S 8 nanoparticles during Li-cycling. As a result, as-synthesized nanocomposites could be successfully operated under ultrawide temperature window of −20 °C–70 °C, rendering excellent electrochemical performances, i.e., remarkable reversible capacities of 910 mA h g −1 after 100 cycles (at 500 mA g −1 ) and 622 mA h g −1 after 200 cycles (at 1000 mA g −1 ) at 70 °C. These attributes enable three-dimensional structured Co 9 S 8 nanoparticles to be promising anode materials of advanced Li-ion batteries for large-power applications such as electric vehicles under extreme temperature environments. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)-encapsulated MnGeO 3 microspheres have been yielded via a facile, scalable and environmentally friendly route. Hydrothermal method was utilized to recrystallize MnGeO 3 particles and form rGO encapsulation. Such rationally designed rGO-encapsulated MnGeO 3 microspheres afforded excellent electrochemical performances, i.e. high first discharge capacity of 1364 mAh g −1 and charge capacity of 810.8 mAh g −1 , and reversible capacity of 624.6 mAh g −1 after 50 cycles at a current density of 200 mA g −1 when they were employed as anode materials for Li ion batteries. These advantageous attributes make rGO-encapsulated MnGeO 3 microspheres the potential anode materials for Li-ion batteries. [ABSTRACT FROM AUTHOR]

Graphene-covered and carbon-encapsulated CoSO 4 nanoparticles (a-C@CoSO 4 @GNs) were first prepared by a facile solution-phase route followed by heat treatment. Subsequently, a-C@CoSO 4 @GNs nanoparticles were utilized as anode materials of Li ion batteries. Such a rationally designed three-dimensional nanostructure could effectively accommodate the volume expansion of CoSO 4 particles during Li-cycling. As a consequence, a-C@CoSO 4 @GNs have delivered remarkable electrochemical performances, i.e., high first discharge capacity (994 mA h g −1 ), prominent cyclic performance of 662.7 mA h g −1 at a current density of 200 mA g −1 and excellent large-current capacity of 497 mA h g −1 at a current density of 1.5 A g −1 after 50 cycles due to catalytically reduced mechanism. More importantly, a-C@CoSO 4 @GNs electrodes possessed outstanding low/high temperature properties, i.e., reversible capacity of 130 mA h g −1 at −20 °C and 1362 mA h g −1 at 60 °C at a current density of 200 mA g −1 . These advantageous attributes make inexpensive, easily available, widespread and non-toxic CoSO 4 promising candidate as anode materials for high-performance lithium-ion batteries under extremely operational environments. [ABSTRACT FROM AUTHOR]