TA is employed as a reducing agent to supply electrons in the hydrothermal reaction, followed by brief annealing to restore the Li ⁺ diffusion pathways along the [010] direction and facilitate the re-intercalation of Li ⁺ in spent LFP.

In this paper, we report a complete solution for enhanced sludge treatment involving the removal of toxic metal (Cu(II)) from waste waters, subsequent pyrolytic conversion of these sludge to Cu-doped porous carbon, and their application in energy storage systems. The morphology, composition, and pore structure of the resultant Cu-doped porous carbon could be readily modulated by varying the flocculation capacity of Cu(II). The results demonstrated that it exhibited outstanding performance for supercapacitor electrode applications. The Cu(II) removal efficiency has been evaluated and compared to the possible energy benefits. The flocculant dosage up to 200 mg·L⁻¹ was an equilibrium point existing between environmental impact and energy, at which more than 99% Cu(II) removal efficiency was achieved, while the resulting annealed product showed a high specific capacity (389.9·F·g⁻¹ at 1·A·g⁻¹) and good cycling stability (4% loss after 2500 cycles) as an electrode material for supercapacitors.

The key to hindering the commercial application of Ni-rich layered cathode is its severe structural and interface degradation during the undesired phase transition (hexagonal to hexagonal (H2 → H3)), degenerating from the build-up of mechanical strain and undesired parasitic reactions. Herein, a perovskite Li_0.35La_0.55TiO₃ (LLTO) layer is built onto Ni-rich cathodes crystal to induce layered@spinel@perovskite heterostructure to solve the root cause of capacity fade. Intensive exploration based on structure characterizations, in situ X-ray diffraction techniques, and first-principles calculations demonstrate that such a unique heterostructure not only can improve the ability of the host structure to withstand the mechanical strain but also provides fast diffusion channels for lithium ions as well as provides a protective barrier against electrolyte corrosion. Impressively, the LLTO modified LiNi_0.9Co_0.05Mn_0.05O₂ cathode manifests an unexpected cyclability with an extremely high-capacity retention of ≈ 94.6% after 100 cycles, which is superior to the pristine LiNi_0.9Co_0.05Mn_0.05O₂ (79.8%). Furthermore, this modified electrode also shows significantly enhanced cycling stability even withstanding a high cut-off voltage of 4.6 V. This surface self-reconstruction strategy provides deep insight into the structure/interface engineering to synergistically stabilize structure stability and regulate the physicochemical properties of Ni-rich cathodes, which will also unlock a new perspective of surface interface engineering for layered cathode materials.

This work demonstrates a scalable and continuous flow production of sulfur nanoparticles (SNPs) using a confined impingement jet mixer (CIJ). Sizes and morphology of SNPs can be easily controlled by varying the micro-mixing degree. Using a high feed-speed equal to 110 mL min⁻¹, spherical composites containing SNPs covered with polyvinylpyrrolidone (S@PVP) with uniform morphology and an average diameter of 485 nm were obtained. These composites were tested as active cathode materials for Li–S batteries. Cathodes containing S@PVP composites exhibited high initial capacity equal to 1030.7 mA h g⁻¹. After 50 cycles at C/10, the capacity was 807.7 mA h g⁻¹. Such excellent capacity and capacity retention were attributed to the small size and homogeneous dispersion of SNPs as well as the conducting PVP layer, which provided effective multidimensional electron and ion transport pathways. The PVP layer also mitigated the problems associated with volume expansion, typically occurring during battery cycling. The simplicity and scalability of the method proposed in this work give it very strong potential for large-scale continuous fabrication of SNPs for Li–S rechargeable batteries.