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Germanium has been recognized as a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity and excellent lithium-ion diffusivity. Nonetheless, it is challenging to enhance both the high-rate performance and long-term cycling stability simultaneously. This study introduces a novel heterostructure composed of germanium nanosheets integrated with graphene (Ge NSs@Gr). These nanosheets undergo an in situ phase transformation from a hydrogen-terminated multilayer germanium compound termed germanane (GeH) derived via topochemical deintercalation from CaGe2. This approach mitigates oxidation and prevents restacking by functionalizing the exfoliated germanane with octadecenoic organic molecules. The resultant germanium nanosheets retain their structural integrity from CaGe2and present an exposed, active (111) surface that features an open crystal lattice, facilitating swift lithium-ion migration conducive to lithium storage. The composite material delivers a substantial reversible capacity of 1220 mA h g–1at a current density of 0.2 C and maintains a capacity of 456 mA h g–1even at an ultrahigh current density of 10 C over extended cycling. Impressively, a capacity of 316 mA h g–1remains after 5000 cycles. The exceptional high-rate performance and durable cycling stability underscore the Ge NSs@Gr anode’s potential as a highly viable option for LIBs.

Bismuth oxide silicate (Bi2O2SiO3) single-crystalline nanosheets with exposed {001} facets were synthesized for the first time viaa facile one-step CTAB-assisted hydrothermal method in the presence of NaOH. Control experiments were carried out to investigate various factors that affect the formation, morphology and exposed planes of the products systematically. The results revealed that the pH and the amount of CTAB play vital roles in the reaction. Bi2O2SiO3nanosheets could not be obtained without the addition of sodium hydroxide solution in the synthesis process, and CTAB not only promotes the exposure of {001} facets, but also modulates the size and thickness of these Bi2O2SiO3nanosheets in a wide range. It was shown that the as-prepared Bi2O2SiO3nanosheets synthesized under the conditions that the amount of CTAB was 4 mmol and the pH value was 12 exhibited higher photocatalytic activities toward RhB and BPA degradation under simulated sunlight irradiation than all the other samples in our experiment, which might give the main credit to the highly exposed {001} facets and considerable number of oxygen vacancies. The present work provides a new reference for the synthesis of Bi2O2SiO3nanosheets and other manipulation of facet-dependent photoreactivity of semiconductors.

Single-crystalline Bi19Cl3S27nanorods have been synthesized for the first time viaa facile solvothermal route. The Bi19Cl3S27nanorods showed high activity for the photocatalytic removal of Cr(vi). In addition, the growth of the nanorods and the generation of active species in the catalysis system were proposed.

In this work, we firstly synthesized metallic Bi-modified Bi4O5I2nanocomposites with oxygen vacancies viaa facile one-pot solvothermal method. The deposited Bi metal and oxygen vacancies endowed the Bi/Bi4O5I2samples with dramatically enhanced photocatalytic performance for degradation of bisphenol A (BPA) and methyl orange (MO) under visible light irradiation. In particular, the improved photocatalytic activity can be ascribed to the synergistic effect of Bi metal and oxygen vacancies, which resulted in their efficient light harvesting properties and excellent charge separation ability. The photocatalytic mechanism of Bi/Bi4O5I2for organics degradation was demonstrated. This work could shed light on exploring high photocatalytic performance materials and stimulating the development of non-noble metal/BixOyIzphotocatalysts, which would also contribute to advancement in environmental remediation and energy exploitation.

A robust three-dimensional (3D) interconnected sulfur host and a polysulfide-proof interlayer are key components in high-performance Li–S batteries. Herein, cellulose-based 3D hierarchical porous carbon (HPC) and two-dimensional (2D) lamellar porous carbon (LPC) are employed as the sulfur host and polysulfide-proof interlayer, respectively, for a Li–S battery. The 3D HPC displays a cross-linked macroporous structure, which allows high sulfur loading and restriction capability and provides unobstructed electrolyte diffusion channels. With a stackable carbon sheet of 2D LPC that has a large plane view size and is ultrathin and porous, the LPC-coated separator effectively inhibits polysulfides. An optimized combination of the HPC and LPC yields an electrode structure that effectively protects the lithium anode against corrosion by polysulfides, giving the cell a high capacity of 1339.4 mAh g−1and high stability, with a capacity decay rate of 0.021% per cycle at 0.2C. This work provides a new understanding of biomaterials and offers a novel strategy to improve the performance of Li–S batteries for practical applications.