The design of binders for lithium-ion batteries is highlighted, with an emphasis on key parameters affecting device performance and failure mechanisms. These issues are discussed in detail using the example of a silicon anode and a sulfur cathode.

The two-step green synthesis of highly stable and well-dispersed copper nanoparticles are obtained by the two-step dehydrogenation mechanism of l-ascorbic acid. The copper nanoparticles can be applied in the biomedicine and flexible electronics.

The past decades have witnessed surging demand for wearable electronics, for which thermoelectrics (TEs) are considered a promising self-charging technology, as they are capable of converting skin heat into electricity directly. Bi₂Te₃ is the most-used TE material at room temperature, due to a high zT of ~1. However, it is different to integrate Bi₂Te₃ for wearable TEs owing to its intrinsic rigidity. Bi₂Te₃ could be flexible when made thin enough, but this implies a small electrical and thermal load, thus severely restricting the power output. Herein, we developed a Bi₂Te₃/nickel foam (NiFoam) composite film through solvothermal deposition of Bi₂Te₃ nanoplates into porous NiFoam. Due to the mesh structure and ductility of Ni Foam, the film, with a thickness of 160 μm, exhibited a high figure of merit for flexibility, 0.016, connoting higher output. Moreover, the film also revealed a high tensile strength of 12.7 ± 0.04 MPa and a maximum elongation rate of 28.8%. In addition, due to the film’s high electrical conductivity and enhanced Seebeck coefficient, an outstanding power factor of 850 μW m⁻¹ K⁻² was achieved, which is among the highest ever reported. A module fabricated with five such n-type legs integrated electrically in series and thermally in parallel showed an output power of 22.8 nW at a temperature gap of 30 K. This work offered a cost-effective avenue for making highly flexible TE films for power supply of wearable electronics by intercalating TE nanoplates into porous and meshed-structure materials.

Molecular oxygen activation often suffers from high energy consumption and low efficiency. Developing eco-friendly and effective photocatalysts remains a key challenge for advancing green molecular oxygen activation. Herein, graphitic carbon nitride (g-C₃N₄) with abundant hydroxyl groups (HCN) was synthesized to investigate the relationship between these polar groups and molecular oxygen activation. The advantage of the hydroxyl group modification of g-C₃N₄ included narrower interlayer distances, a larger specific surface area and improved hydrophilicity. Various photoelectronic measurements revealed that the introduced hydroxyl groups reduced the charge transfer resistance of HCN, resulting in accelerated charge separation and migration kinetics. Therefore, the optimal HCN-90 showed the highest activity for Rhodamine B photodegradation with a reaction time of 30 min and an apparent rate constant of 0.125 min⁻¹, surpassing most other g-C₃N₄ composites. This enhanced activity was attributed to the adjusted band structure achieved through polar functional group modification. The modification of polar functional groups could alter the energy band structure of photocatalysts, narrow band gap, enhance visible-light absorption, and improve photogenerated carrier separation efficiency. This work highlights the significant potential of polar functional groups in tuning the structure of g-C₃N₄ to enhance efficient molecular oxygen activation.