Luffa sponge, as a renewable precursor, is used for the first time to synthesize sulfur-doped microporous carbon (SMPC), which is subsequently rolled into an SMPC interlayer that acts as the polysulfide diffusion inhibitor between a sulfur cathode and separator in a Li–S battery. Instrumental analysis shows that the obtained SMPC possesses a unique microporous carbon framework, large specific surface area (3211.2 m² g⁻¹), high pore volume (1.72 cm³ g⁻¹), good electrical conductivity (1.89 S cm⁻¹) and in situ S-doping (2.72 at%). Due to the special physical properties and chemical ingredients of SMPC, the as-fabricated SMPC interlayer for Li–S batteries can not only facilitate rapid electron and Li ion transfer, but can also effectively sequester dissolved polysulfides through combining strong chemical and physical absorption. Consequently, Li–S batteries containing the SMPC interlayer deliver a high initial reversible capacity (1544.2 mA h g⁻¹ at 0.2C), superior rate capability (781.2 mA h g⁻¹ at 5C), and excellent cycling stability (over 500 cycles at 2C with 0.057% capacity fading per cycle). This eco-friendly, low cost SMPC interlayer can offer an appealing alternative for the commercialized production of Li–S cells.

N-doped nanoporous graphitic carbon has attracted great interest because of its distinctive structure and physical properties. In this paper, we have proposed a novel method to control Ni-induced graphitization by diffusing Ni nanoparticles from graphitic carbon spheres into N-doped amorphous carbon nanofibers, which turns amorphous carbon into graphitic carbon and produces a hollow-tunnel structure in electrospun carbon/Ni nanofibers. The resultant materials were further treated by chemical activation and acid treatment to develop activated N-doped hollow-tunneled graphitic carbon nanofibers (ANHTGCNs). In a typical application, we demonstrate that ANHTGCNs are excellent anode materials for lithium ion batteries (LIBs), displaying a superhigh reversible specific capacity of ∼1560 mA h g⁻¹ and a remarkable volumetric capacity of ∼1.8 A h cm⁻³ at a current density of 0.1 A g⁻¹ with outstanding rate capability and good cycling stability.

Silicon-based anodes have recently received increased attention due to their high theoretical capacity. However, the Si-based anodes always suffer from a large volume change during cycling and require expensive and multistep processes to prepare nano-sized Si. In this work, Si nanoparticles are successfully embedded in a carbon matrix by using NaCl particles as a hard template, which were prepared through magnesiothermic reduction of SiO₂ nanoparticles. Besides, NaCl particles also play an important role in absorbing the local heat accumulation generated from magnesiothermic reduction, thus preventing the agglomeration of Si particles and the formation of undesirable SiC. The as-prepared Si@PCM could not only provide fast electron diffusion through carbon networks, but also accommodate the stress–strain caused by the volume change. As a result, the Si@PCM composite demonstrates an excellent electrochemical performance as an anode material for lithium-ion batteries.