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Yolk-shell structured nano-Si@void@C can greatly improve the electrical conductivity and buffer the large volume change of silicon nanoparticles, whereas inter poor electrical connection between Si cores and carbon shells still limits the lithium storage performance. Besides, it usually requires complex synthesis conditions and expensive nano-level silicon sources. Herein, we succeed in making the large-size industrial silicon ( ca . 400–500 nm) to a yolk-shell structure with a controllable space buffer layer. Most importantly, an interconnected porous carbon network deriving from the thermal decomposition of carbon chains in silicon sources is formed within the carbon shell simultaneously, which can improve the electrical contact between Si cores and hollow carbon shells and prevent the active particles exposure to the electrolyte. With the help of static outer thin carbon shell, optimized inner void and the flexible electrically conductive carbon network, such yolk-shell structured Si@void@C submicron particles synthesizing by one-step carbon-coating procedure exhibit high initial coulomb efficiency of 62%, good rate performance, and excellent long cycling stability with 950.7 mAh g −1  at 100 mA g −1 after 100 cycles. The low consumption and stable synthesis method make it feasible for large-scale fabrication of the yolk-shell structured Si/C composites as commercial anodes for energy storage. [ABSTRACT FROM AUTHOR]

In this paper, an ultrathin layer of acid treated multiwalled carbon nanotubes (CNTs) are conformally wrapped on everyday cotton textiles for subsequently controlled electrodeposition of MnO 2 nanoflakes. The general morphology and detailed microstructure of the as-prepared composites are characterized and the formation mechanism is investigated by time-dependent experiments. Such conductive textiles show outstanding flexibility and strong adhesion between the CNTs and the textiles of interest. Supercapacitors made from these ternary conductive textiles show high specific capacitance up to 247 F·g −1 at 1 A·g −1 . A capacity retention of 94.7% can be maintained at 2000 continuous charge-discharge cycles, after which the textiles electrode essentially maintained its whole structural integrity. The discharge curves remain unchanged with a slight capacitance decrease even under vertical folding condition. All these demonstrate that hybrid flexible electrode of MnO 2 and conductive textile is an effective strategy towards high-energy supercapacitors and may provide a promising design direction for optimizing the electrochemical performance of insulating metal oxide based on electrode materials. [ABSTRACT FROM AUTHOR]

• Graphene bubble film encapsulated Si@C hollow spheres is designed as LIB anodes. • Si hollow spheres are wrapped by interior CVD carbon shell and external GNS layers. • Carbon shell inhibits si particles agglomeration and detrimental interface reactions. • Graphene bubble film enhances structural stability and electronic conductivity. • Enhanced electrochemical performances are presented compared to H-Si@C and G/H-Si. Silicon-based composites have been proposed as the promising anode materials for Li-ion batteries. In order to avoid the operational problems of silicon-based anodes such as the low electric conductivity and huge volume expansion, we succeed in encapsulating Si@C hollow spheres into flexible graphene bubble film as a durable anode with enhanced lithium storage properties. In this design, sub-micrometer-sized Si hollow spheres are wrapped into accessible mesoporous carbon shells. Then, the Si@C hollow spheres are tightly wrapped with amino-functionalized graphene oxide nanosheets and followed by chemical reduction to form a bubble film composite structure. Such closely packed graphene bubble films encapsulating hollow Si@C macrostructure ensures uniform and aggregation-free distribution of silicon spheres in the dual conductive carbon network. This kind of graceful composite structure can not only suppress volume expansion and improve structural stability of the electrode material, but also facilitate the electron transfer and lithium ion migration by shortening the transportation channels. The as-prepared composite exhibits impressive Li storage performance with a high reversible capacity of 813.2 mAh g −1 after 100 cycles at 0.1C. This work offers an appealing strategy for high-performance Si-based anode materials in practical application. Image, graphical abstract [ABSTRACT FROM AUTHOR]