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A facile strategy is designed for the fabrication of flexible and free-standing ternary CoSnO 3 /graphene/carbon nanotubes (CoSnO 3 /GN/CNTs) composite papers through a simple filtration, followed by annealing process. The CoSnO 3 /GN/CNTs composite papers with high flexibility and tailorability can be easily fabricated. The CoSn(OH) 6 nanoparticles/graphene oxide/carbon nanotubes (CoSn(OH) 6 /GO/CNTs) composite papers obtained by a simple filtration method are transformed into CoSnO 3 /GN/CNTs composite papers after a thermal treatment process. In this unique composite structure, CoSnO 3 nanoparticles (nanocubes and nanoboxes) are embedded homogenously into the 3D framework of graphene and carbon nanotubes, respectively, in which offers not only a 3D conductive network and a dual restriction on the aggregation of CoSnO 3 nanoparticles, but also accommodates the large volume expansion of CoSnO 3 nanoparticles. When used directly as binder- and conductive agent-free anodes for lithium-ion batteries, the CoSnO 3 /GN/CNTs composite papers exhibit superb electrochemical properties including extraordinary reversible capacities, superior rate capabilities and stable cycle performances compared to CoSnO 3 nanoparticles and GN/CNTs paper, suggesting a new pathway for the rational engineering of anode materials. [ABSTRACT FROM AUTHOR]

Abstract: SnO2–graphene–carbon nanotube (SnO2–G–CNT) mixture is synthesized using graphene oxide as precursor for application as anode material in rechargeable Li ion batteries. It is shown that the SnO2 nanoparticles of 3–6nm in diameter are not only attached onto the surface of graphene sheets by anchoring with surface functional groups, but they also are encapsulated in pore channels formed by entangled graphene sheets. The incorporation of carbon nanotubes reduces the charge transfer resistance of the anode made from the mixture through the formation of 3D electronic conductive networks. The SnO2–G–CNT anodes deliver remarkable capacities of 345 and 635mAhg−1 at 1.5 and 0.25Ag−1, respectively. Flexible electrodes consisting of highly-aligned SnO2–G–CNT papers are also prepared using a simple vacuum filtration technique. They present a stable capacity of 387mAhg−1 at 0.1Ag−1 after 50 cycles through the synergy of the high specific capacity of SnO2 nanoparticles and the excellent cycleability of G–CNT paper. [Copyright &y& Elsevier]