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To address the persistent challenge of soluble lithium polysulfides (LiPSs) migration in lithium-sulfur batteries, this study introduces a functional conductive interlayer derived from a cost-effective porous carbon film, innovatively synthesized through one-step carbonization of pitaya peel waste. The porous structure and abundant oxygen-containing functional groups in the resulting film successfully restrict LiPSs diffusion and boost the redox dynamics of LiPSs. Electrochemical evaluation reveals that the sulfur cathode with the proposed interlayer outperforms a pure sulfur cathode, exhibiting superior discharge capacity and cycling stability. The research presents a simplified and economical method for interlayer fabrication, contributing to sustainable advancements in lithium-sulfur battery technology. [Display omitted] • The waste pitaya peel was used as a precursor to fabricate carbon film. • The free-standing carbon film was prepared through one-step carbonization. • The derived carbon film can be used as an effective interlayer for high-performance lithium sulfur battery. [ABSTRACT FROM AUTHOR]

A TiO 2 /SiO x /Si composite derived from cellulosic cotton as the structural template was biomimetically synthesized. Modified sol–gel deposition processes were performed to coat each cellulose nanofiber with a SiO 2 thin gel layer, followed by layer-by-layer self-assembly processes to form an external TiO 2 coating with controllable thickness. The resulted matter was calcined in air to obtain the TiO 2 /SiO 2 composite, which was successively put in N 2 atmosphere and treated with magnesiothermic reduction reaction, resulting in the final TiO 2 /SiO x /Si composite. The composite possessed a typical hierarchical three-dimensional (3D) nanotubular network microstructure precisely inherited from the cellulosic cotton template, and each nanotube had a core-shell nanostructure with Si-based matters as the core and TiO 2 coating as the shell. Compared with the bare nanotubular SiO x /Si material, the TiO 2 /SiO x /Si composite showed a highly enhanced electrochemical performance as an anode material for lithium-ion batteries (LIBs), delivering an initial discharge capacity of 2370 mAh g−1 at a current density of 0.2 A g−1 (an initial Coulombic efficiency of 56.4%), a reversible capacity of 682 mAh g−1 after 100 discharge/charge cycles, and a discharge capacity of 241 mAh g−1 at a high current density of 2.0 A g−1. The excellent specific capacity, cycling stability and rate capability are ascribed to the synergistic effect of the unique 3D porous nanotubular network structure and the uniform TiO 2 coating layer, which accommodates the volume variation of Si-based components during cycling, offers sufficient ion transport pathways and improves the electron transfer efficiency. This work provides a facile biomass-based strategy for fabrication of metal oxide/Si composites with well-defined microstructures that exhibit significant potential as anode materials for LIBs. TiO 2 /SiO x /Si composite with hierarchical nanotubular network microstructure derived from cellulosic cotton was biomimetically synthesized, showing highly improved electrochemical performance as an anode material for lithium-ion batteries. [Display omitted] • A cellulosic cotton derived TiO 2 /SiO x /Si composite was biomimetically synthesized. • Si-based nanotube was coated by TiO 2 nanoparticles entirely and uniformly. • It exhibited highly improved cycling stability and rate capacity as an anode material for lithium-ion batteries. • The microstructure of TiO 2 coating and hierarchical network contribute to the enhanced electrochemical performance. [ABSTRACT FROM AUTHOR]