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A sandwichlike magnesium silicate/reduced graphene oxide nanocomposite (MgSi/RGO) with high adsorption efficiency of organic dye and lead ion was synthesized by a hydrothermal approach. MgSi nanopetals were formed in situ on both sides of RGO sheets. The nanocomposite with good dispersion of nanopetals exhibits a high specific surface area of 450 m(2)/g and a good mass transportation property. Compared to MgSi and RGO, the mechanical stability and adsorption capacity of the nanocomposite is significantly improved due to the synergistic effect. The maximum adsorption capacities for methylene blue and lead ion are 433 and 416 mg/g, respectively.

Graphene was coated with SiO2 nanoparticles by a sol–gel approach and the coated graphene sheets are efficient in improving the thermal conductivity of epoxy while retaining its electrical insulation.

Layered nickel silicate provides massive interlayer space that is similar to graphite for the insertion and extraction of lithium ions and sodium ions; however, the poor electrical conductivity limits its electrochemical application in energy storage devices. Herein, carbon nanotube@layered nickel silicate (CNT@NiSiOx) coaxial nanocables with flexible nickel silicate nanosheets grown on conductive carbon 10 nanotubes (CNTs) are synthesized with a mild hydrothermal method. CNTs serve as the conductive cables to improve the electron transfer performance of nickel silicate nanosheets, resulting in reduced contact and charge-transfer resistances. In addition to high specific surface area, short ion diffusion distance and good electrical conductivity, the one-dimensional coaxial nanocables have a stable structure to sustain volume change and avoid structure destruction during the charge/discharge process. As an 15 anode material for lithium storage, the first cycle charge capacity of the CNT@NiSiOx nanocables reaches 770 mA h/g with the first cycle Coulombic efficiency as high as 71.5 %. Even after 50 cycles, the charge capacity still reaches 489 mA h/g at a current density of 50 mA/g, which is nearly 87 % and 360 % higher than those of NiSi/CNT mixture and nickel silicate nanotube, respectively. As anode material for sodium storage, the coaxial nanocables exhibit a high initial charge capacity of 576 mA h/g, which even 20 retains 213 mA h/g at 20 mA/g after 16 cycles. 65 By adjusting the amount of carbon precursor, the interlayer spacing could be altered between 1.22 to 3.37 nm, the specific capacity increased from 232 mA h/g for neat zinc silicate, to 455 mA h/g for zinc silicate/interlayer carbon composite, and further 85 bonded to CNT, CNT@NiSiOx nanocables exhibit good mechanical, thermal and cycling stability. The combination of NiSiOx and CNT shows good synergistic effect by increasing the lithium storage capacity and improving the electron and lithium ion diffusion efficiency of the nanocables. For lithium storage, 90 the charge capacity of CNT@NiSiOx after 50 cycles retains 489 TOC 5 Carbon nanotube@layered nickel silicate (CNT@NiSiOx) coaxial nanocables with flexible nickel silicate nanosheets grown on conductive carbon nanotubes (CNTs) are synthesized by a mild hydrothermal method. Massive interlayer space for lithium or sodium storage, improved electrical conductivity and C-O-Si 10 covalent bonding are benefit for structure stability during discharge/charge cycles and enhanced electrochemical property.

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The combination of active materials with electrically conductive carbon materials and their contact efficiency are crucial for improving the electrochemical performances of active materials. Here, nickel silicate (NiSiOx) nanoplates are planted in situ on the surface of reduced graphene oxide (RGO) nanosheets to form a two dimensional face-to-face nanocomposite of NiSiOx/RGO for lithium storage. The face-to-face structure enhances the contact efficiency of NiSiOx with RGO, and thus leads to a higher reversible capacity and better rate performance of the NiSiOx/RGO nanocomposite than both carbon nanotube (CNT)@NiSiOx nanocables and NiSiOx. The layered NiSiOx/RGO nanocomposite exhibits a high reversible specific capacity of 797 mA h g(-1), which is 62% and 806% higher than those of CNT@NiSiOx nanocables and NiSiOx alone, respectively.