Lin Zhu

Polyoxymethylene (POM) is increasingly used to replace metals in moving components because of its corrosion resistance and high specific strength; however, its insufficient heat resistance and wear resistance limit its application under demanding service conditions. In this study, bisphenol-A/aniline-based benzoxazine (BZ) was used as a low-loading modifier, and BZ/POM composites were prepared by melt blending (210 °C) and compression molding (220 °C) while exploiting the thermal ring-opening polymerization of BZ within the POM processing range. The effects of BZ content (0–0.5 wt%) on the mechanical, thermal, and tribological properties were investigated. All properties showed non-monotonic behavior: the optimum mechanical performance was obtained at 0.3–0.4 wt% BZ (tensile strength +15.2% and flexural strength +62.7%), the decomposition temperature increased monotonically (temperature at the maximum decomposition rate +19 °C), and the coefficient of friction decreased in a threshold-like manner to a minimum of 0.1192 at 0.4 wt% BZ (a reduction of 29.3%). A BZ content of 0.4 wt% provided the best overall balance among the mechanical, thermal, and tribological properties, offering a new route for modifying thermoplastic engineering plastics through the in-situ polymerization of thermosetting monomers.

Aqueous zinc-ion batteries (AZIBs) have garnered extensive attention owing to their advantages of low cost, high safety, and environmental friendliness. However, the zinc anode suffers from several critical issues during charge–discharge cycles, such as zinc dendrite growth, electrolyte corrosion, and hydrogen evolution side reactions, which drastically degrade the Coulombic efficiency and cycle life of the batteries. Biomass-derived carbon (BC) materials are particularly attractive because of their abundance, low cost, and diverse functional groups. In this study, a composite coating material (MoS2/BC) is synthesized via a hydrothermal method and applied to the surface of zinc anodes for the AZIBs. The MoS2 nanoflowers assembled from two-dimensional (2D) nanosheets and anchored on flaky BC can significantly expand the interfacial area and enhance the reaction activity. Furthermore, the stacking of multilayered MoS2 nanosheets can effectively improve the mechanical strength of the material, maintain the structural stability of the coating during cycling, and prevent battery failure caused by the peeling off of the coating during long-term charge–discharge cycles. Additionally, the interlayer spacing of MoS2 nanosheets can induce the intercalation of hydrated Zn2+ ions, thus promoting uniform deposition of zinc. The corresponding symmetric cell achieves stable cycling for 2600 h at a current density of 1 mA cm–2 and an areal capacity of 0.15 mAh cm–2. When assembled into a full cell, it maintains a capacity retention rate of 71.0% after 2400 cycles at a high current density of 3 A g–1 with a relatively high initial discharge capacity.

Porphyrin organic frameworks (POFs) have garnered significant interest within the realm of organic framework materials, which is largely attributed to their conjugated molecular architecture and well-ordered pore channels. In this study, zinc metal was coordinated with porphyrin, and carbon nanotubes (CNTs) were employed as a template to synthesize the CNT@POF composite. The high conductivity and enhanced ion transport capability of CNTs were synergistically combined with the porphyrin system to construct an interfacial protective layer on the Zn anode for aqueous Zn-ion batteries (AZIBs). This present design is intended to inhibit undesirable parasitic reactions, namely, dendrite formation, chemical corrosion, electrode passivation, and hydrogen evolution. Long-term cycling results prove that the symmetric cell featuring this protective coating can operate stably for 1150 h while operated at 3 mA cm^-2 and 1 mAh cm^-2. Furthermore, after 4000 cycles at 5 A g^-1, the full cell retains a specific capacity of 93.5 mAh g^-1, equating to a capacity retention of 85.5%. The present research presents an interfacial modification strategy based on metal-coordinated porphyrin and template-assisted synthesis, providing a viable route to realizing dendrite-free Zn anodes for high-performing AZIBs.

Polyoxymethylene (POM), a widely used engineering plastic, is a highly crystalline thermoplastic polymer known for its mechanical strength, fatigue resistance, and chemical stability. POM is increasingly used as a substitute for metal in various applications, making it essential to continuously enhance its performance. Many researchers have investigated the modification of POM and proposed various methods for preparing POM composites, particularly emphasizing the use of nanomaterials as reinforcing agents. This review systematically summarizes the mechanical, thermal, crystallization, and tribological properties of POM and its nanocomposites (e.g., Nano-SiO ₂ , Nano-Al ₂ O ₃ , Nano-ZnO, Carbon Nanotube, POSS, Hydroxyapatite, Nano-MoS ₂ , MMT). Additionally, it focuses significantly on examining their application prospects, aiming to offer more optimal solutions for the utilization of POM. It is anticipated that this review will establish a robust theoretical foundation for future research in the field of POM and its nanocomposites and will also facilitate the effective deployment of POM-based materials across a broader range of critical fields.

Aqueous zinc ion batteries (AZIBs) have emerged as a promising member of the emerging energy storage battery family, attributed to their merits such as low cost, high safety, and environmental friendliness. However, their practical applications have been hampered by issues like side reactions and the growth of zinc dendrites. In this paper, we developed a method to prepare reduced graphene oxide (rGO)-attached biomass carbon composites (rGO/BC) for coating the zinc anode surface by using a simple hydrothermal method. Firstly, rGO was incorporated to offer more Zn-friendly sites, effectively suppressing the growth of zinc dendrites. Secondly, the flexible structure of rGO not only enhanced the reaction kinetics but also improved the structural stability of the rGO/BC composites. In addition, the synergistic effect of rGO and BC resulted in excellent electrical conductivity and electrolyte wettability of the zinc anode, thereby reducing the interfacial resistance. Thanks to these advantages, the AZIBs assembled with the rGO/BC@Zn anode exhibited excellent electrochemical performance. In composite experiments with different ratios, the symmetric cell assembled with rGO/BC-5, which demonstrated the best performance, had a low overpotential and achieved a cycle life of 2400 h at 1 mA cm⁻² and 0.15 mA h cm⁻². When this anode was paired with VO₂, the rGO/BC-5@Zn//VO₂ full cell showed outstanding cycling performance, maintaining a capacity retention of 83% after 2400 cycles at 5 A g⁻¹. This work presents a novel interfacial approach for modifying zinc anodes with biomass-carbon composites, providing valuable insights for the development of high-performance AZIBs.

Cu₂Se@BC was constructed to improve the structural stability of Zn anodes. It can induce the preferential orientation of zinc ions on the Zn (002) crystal plane. The AZIBs assembled with the Cu₂Se@BC–Zn anode showed good electrochemical performance.