Lixin Song

Two-dimensional (2D) MXene membranes have emerged as a focal platform for ionic separations owing to their exceptional mechanical flexibility, intrinsic hydrophilicity, abundant surface terminations, and high electrical conductivity. This review summarizes recent advances in MXene-based membranes, with an emphasis on structural engineering strategies and their translation to ion-separation applications. We first outline representative fabrication routes for MXene membranes. We then discuss how separation mechanisms can be understood and deliberately tuned across four key scenarios: monovalent/monovalent ion separations, monovalent/multivalent ion separations, anion/cation separations, and heavy-metal ion separations. Finally, we highlight outstanding challenges and future opportunities, aiming to provide actionable guidance for the rational design and scalable manufacturing of high-performance MXene membranes for ionic separations.

To address the narrow application range of PBAT/PLA blends caused by component incompatibility, this study selected four compatibilizers and compared the effects of different compatibilizers on the properties of the blends: these included a commercially available styrene-acrylate copolymer (HPC), as well as three synthesized compatibilizers: PBAT-g-(GMA-co-St) graft copolymer, epoxidized soybean oil–cardanol derivative (ESO–CD), and N-carboxymethyl triethylammonium bromide (CEA). The chemical structures of three compatibilizers were characterized via FTIR, ¹H-NMR and ¹³C-NMR to confirm successful synthesis. Subsequently, corresponding PBAT/PLA blends were prepared via melt blending and tested for compatibility, matrix dispersion, crystallization behavior, rheological properties, and mechanical performance. Results indicate that all prepared compatibilizers improve PBAT/PLA blend compatibility and PLA dispersion within the PBAT matrix to varying degrees. Specifically, PBAT-g-(GMA-co-St) and HPC compatibilizers enhanced compatibility by reacting their epoxy groups with the molecular chains, significantly narrowing the glass transition temperature gap between PBAT and PLA components. ESO–CD, containing both epoxy bonds and hydroxyl groups, further strengthened compatibility while markedly improving the blend's elongation at break and toughness. CEA compatibilizer reduces the ΔT_g of the blend to a minimum by increasing the interfacial strength between components in the blend, produced the most uniform PLA phase size, and substantially enhanced interfacial adhesion. This resulted in the highest tensile strength (approximately 25.5 MPa) and elongation at break (approximately 404.9%) for the PBAT/PLA/CEA blend, with the elastic modulus increasing to approximately 777 MPa. Regarding crystallization behavior, DSC and XRD tests revealed that CEA promotes PLA nucleation, inducing new α-crystalline diffraction peaks in the PLA phase of the blend. This significantly advances the crystallization temperature (T_c) and enhances crystallization capability. Furthermore, although the addition of the compatibilizer improved the compatibility of the PBAT/PLA blend, its rheological behavior remained predominantly viscous. In summary, the CEA compatibilizer demonstrated optimal performance in enhancing the comprehensive properties of PBAT/PLA blends, providing crucial insights for the optimized design of biodegradable plastics.

K/Na co-doping synergistically enhances carbon nitride's photoluminescence and exceptional thermal-UV durability.

With the increasing demand for portable electronics, distributed sensors, and self-powered devices, triboelectric nanogenerators (TENGs) have emerged as promising technologies for harvesting ambient mechanical energy.

Core–shell structured CNDs achieve solid-state red fluorescence with a large Stokes shift, boosting the plant chlorophyll content by 58.8%.

This work investigated the thermo‐mechanical properties of phenolphthalein polyether sulfone (PES‐C) in toughening epoxy resin and CFRP, along with an analysis of toughening mechanisms. PES‐C, a high‐performance resin with a high glass transition temperature and modulus due to its specific cardo ring structure and sulfone group, was synthesized and incorporated into epoxy resin through physical blending to enhance the mechanical properties of the epoxy matrix. With the addition of 15 phr PES‐C the impact strength increased by 72.71 %, and SEM analysis revealed a bi‐continuous and island coexistence structure, with the toughening mechanism attributed to reaction‐induced phase separation. The thermal performance was improved, with T _d5% and T _g increased using TGA and DMA analyses. Additionally, PES‐C non‐woven fabric was fabricated via electrospinning and integrated into EP/CF prepregs for interlayer toughening. G _{I, C,} and G _{II, C} of CFRP increased by 37.5 % and 134 %, respectively. The toughening mechanism could be attributed to the enhanced interlayer bonding strength provided by the PES‐C non‐woven fabric, which effectively mitigated fiber debonding. These two approaches demonstrated that PES‐C exhibited excellent toughening effects on both epoxy resin and CFRP, offering significant application potential in the aerospace field.

The introduction of reactive groups capable of participating in epoxy cross-linking into the molecular chains of conventional thermoplastic toughening agents effectively enhances the interfacial compatibility between thermoplastic and thermosetting resins, resulting in a significant improvement in system impact toughness. Building on this approach, this study innovatively incorporates polar nitrile groups into the molecular chains of thermoplastic polyaryletherketone agents containing terminal reactive groups, thereby exploring the synergistic mechanism between reactive and nitrile groups. A systematic investigation is conducted to examine how variations in the nitrile group content and the addition level of the toughening agent influence the toughening effect of epoxy resin. Additionally, the influence of different epoxy system phase structures on mechanical properties is assessed. Experimental results reveal that when the toughening agent PEKCN-OH is added at less than 10 parts per hundred resin (phr), the epoxy system exhibits a sea-island morphology, with the impact strength decreasing with increasing nitrile group content. When no nitrile groups are present (using PEKC-OH resin), the impact strength reaches 23.5 kJ m⁻², representing a 97% increase compared to the control without the toughening agent. For addition levels exceeding 10 phr, the system transitions to a bicontinuous structure. In this regime, the impact strength initially increases before decreasing as the nitrile group content increases. At a nitrile group content of 50% (using PEKCN-OH-2 resin), the impact strength reaches 25.8 kJ m⁻², representing a 117% increase. Importantly, the addition of these toughening agents not only prevents a reduction in the service temperature of the epoxy resin but also enhances its thermal stability. In conclusion, the PEKCN-OH developed in this study serves as a highly efficient, easily prepared reactive thermoplastic toughening agent suitable for industrial production. It holds great promise for use in demanding industrial applications, including aerospace, electronics and electrical appliances, and automotive manufacturing. The findings are expected to make significant contributions to material innovation and product performance optimization in these sectors.