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To buffer the volume expansion of silicon during charge-discharge process, a 3D carbon-coated stable silicon/graphene/CNT (C@Si/GN/CNT/PDA-C) composite was prepared. Si nanoparticles (SiNPs) were first modified by hexadecyl trimethyl ammonium bromide (CTAB) to enhance their stability and dispersibility in water, then uniformly distributed in graphene/carbon nanotubes (GN/CNT) by electrostatic self-assembly, and ultimately encapsulated by carbonized poly-dopamine carbon layer (PDA-C) at high-temperature. PDA-C not only alleviates the volume expansion of Si and inhibits the direct contact of Si with electrolyte, but also acts as a bridge between the conductive GN/CNT and Si to maintain electrode integrity. As an anode material for lithium-ion batteries, the C@Si/GN/CNT/PDA-C exhibits a superior reversible capacity of 1946 mAh g − 1 after 100 cycles with the capacity retention of 68.9% at a current density of 0.1 A g − 1, and over 1306 mAh g − 1 after 100 cycles at 1 A g − 1. The excellent electrochemical performance of C@Si/GN/CNT/PDA-C is attributed to the stable hierarchical structure. [Display omitted] [ABSTRACT FROM AUTHOR]

• The crystalline silicon nanoparticles coated with an amorphous silicon layer (a-coated-c-SiNPs) were continuously prepared by non-thermal plasma pyrolyzing of silane with the help of hydrogen and argon. • The a-Si layer with good tolerance to volume expansion prevented the electrode pulverization, while the c-Si improved the electronic conductivity. The crystallinity of the a-coated-c-SiNPs was controled by the hydrogen etching. • The combination of a-coated-c-SiNPs with a three-component polymer binder (PAA-PVA/SBR) improved the electrochemical performance of Si-based anode. The crystalline silicon nanoparticles coated with an amorphous silicon layer was prepared by continuously pyrolysing the mixture of silane and hydrogen in a non-thermal arc plasma reactor. The hydrogen in the gas mixture effectively controls the thickness of the amorphous silicon layer and further improves the electrochemical performance of the silicon anode. The mechanism of the hydrogen was investigated by experiments. At the same time, a three-component polymer binder was concocted and introduced to tolerate the volume expansion of silicon effectively. Combining the silicon nanoparticles prepared at the optimal conditions with the novel polymer binder, the resulting silicon anode exhibits excellent electrochemical performance of 2120 mAh g−1 at 400 mA g−1 after 100 cycles. [Display omitted] [ABSTRACT FROM AUTHOR]