Xiaofeng Li

Global freshwater scarcity urgently demands sustainable, energy-efficient desalination technologies, and solar-driven interfacial evaporation is a highly promising solution. Hydrogels are attractive evaporator materials because they enable continuous water supply and flexible structural design. However, developing durable hydrogel evaporators combining excellent photothermal conversion, rapid multidirectional water−salt transport, and outstanding salt resistance remains a significant challenge. Herein, a pyramidal poly(vinyl alcohol) (PVA)/Ti3C2Tx MXene composite hydrogel evaporator is fabricated by directional freezing and low-temperature cross-linking. MXene provides excellent broadband solar absorption and photothermal conversion, while a uniquely designed anisotropic architecture combining honeycomb-like and lamellar channels enables rapid vertical and lateral water−salt transport. The pyramidal geometry enlarges the effective evaporation area, while siphon-assisted water supply directs salt crystallization toward the bottom of the evaporator. Under 1 sun irradiation, the evaporator achieves an excellent evaporation rate of 2.38 kg m−2 h−1, and during a 70 h long-term test with a 15 wt % NaCl solution, it maintains an average evaporation rate of 2.20 kg m−2 h−1 while enabling directional salt recovery. It also preserves its shape and evaporation performance upon dehydration-rehydration cycling, demonstrating good reusability. This work offers an effective strategy for high-performance seawater desalination and salt recovery.

Solar‐driven interfacial evaporation offers a sustainable route to alleviating global agricultural water scarcity, yet intrinsic energetic barriers at the gas–liquid interface limit its practical efficiency. Here, we report an electrospun nonwoven nanofibrous hydrogel fabric that combines textile‐like flexibility in the dry state with hydrogel functionality upon hydration. By synergizing the nanoscale interfacial compartmentalization of the fabric architecture with the molecular‐level regulation of functional groups, this material effectively disrupts long‐range cooperative hydrogen‐bonding networks, transforming bulk‐like water into less‐associated, more volatile water states. Crucially, we reveal a counterintuitive seawater‐induced activation mechanism, in which sodium ions trigger an ion‐exchange process that expands the polymer network and exposes hidden active sites. This dynamic activation delivers an exceptional salt‐enhanced evaporation rate of 2.92 kg m ⁻² h ⁻¹ for a 2D planar evaporator in natural seawater under 1 sun illumination. Validated through large‐area fabrication and winter field trials for greenhouse crop irrigation, this scalable architecture provides a robust, decentralized strategy for global agricultural water security.

Engineering interfacial electronic interactions between physically distinct metal oxides without phase transformation, doping, or lattice fusion remains a central challenge of interface science. Conventional Cu₂O–ZnO systems rely on heterojunction formation or compositional mixing, whereas carbon-mediated electronic coupling between discrete phases remains largely unexplored. Here, we report strongly electronically coupled carbon-bridged Cu₂O/ZnO nanocomposites (Cu₂O–C–ZnO NCs) synthesized by incorporating spherical Cu₂O and diamond-shaped ZnO nanoparticles into a gallic-acid-derived carbon framework. Structural and compositional analyses confirm the coexistence of crystalline Cu₂O and ZnO interlocked in a homogeneous carbon matrix, with oxygenated carbon functionalities verified spectroscopically. X-ray photoelectron spectroscopy reveals binding energy shifts in Cu and Zn core levels, providing direct evidence of interfacial electronic coupling and charge redistribution without lattice fusion or heterojunction formation. This electronic interface coupling helps regulate charge transfer between the oxide materials, allowing the controlled release of metal ions and enhancing the generation of reactive oxygen species. As a functional consequence, the NCs exhibit significant antibacterial activity against Gram-negative and Gram-positive bacteria, as well as substantial antialgal activity against freshwater species. Mechanistic evidence validates that the activity stems from a synergy of phenomena, including controlled ion release, ROS, and membrane damage due to oxidative stress, supported by findings from enzymatic and cellular assays. These results demonstrate that carbon-mediated interfacial electronic coupling is a viable method for controlling the surface reactivity of multicomponent oxide systems with the intact structural integrity of individual components.

The widespread application of nuclear technology in fields such as energy, medicine, and aerospace has driven the rapid development of high-performance X/γ-ray shielding materials. This work utilized radiation shielding simulation tools, WinXCom and Geant4, to simulate the X/γ-ray shielding performance of heavy-metal/rare-earth metal oxides. Based on the principle of complementary absorption edges, Bi₂O₃ and Sm₂O₃ were selected as the optimal shielding components. Three-dimensional models of electrospun membranes were established to systematically investigate the influence of different shielding configurations (single, blended, and core–shell structures) on their X/γ-ray shielding performance. Guided by simulation, coaxial electrospinning technology was employed to load Bi₂O₃ and Sm₂O₃ nanoparticles into the shell and core layers of polyacrylonitrile (PAN) nanofibers, respectively, fabricating a hierarchical heteromorphic core–shell nanofibrous membrane (C-SNM). Owing to the complementary absorption characteristics and the multistage shielding attenuation mechanism, a 2 mm thick C_Sm-S_BiNM (70 wt % filler loading) achieved an X-ray shielding efficiency of 52.54% at 80 kV, equivalent to 0.25 mm Pb, while its density was 0.492 g cm^–3, merely 4.34% of the Pb plate (11.344 g cm^–3). Without weight increase, component optimization and configuration design enhanced shielding performance of the C_Sm-S_BiNM by about 4%, compared to a uniaxial nanofibrous membrane (UNM) with a disordered blended structure. Furthermore, the C_Sm-S_BiNM exhibited a water vapor transmission rate of 6.582 kg m^–2 d^–1 and PM2.5 filtration efficiency exceeding 99.960%. The C-SNM combines efficient, broad-spectrum radiation protection with lightweight and moisture-permeable properties, overcoming the limitations of traditional rubber/plastic-based materials in this regard, and laying a foundation for next-generation radiation protection materials.

Flexible, self‐powered thermoelectric (TE) temperature sensors are essential for next‐generation human‐machine systems, yet their practical deployment is hampered by a persistent trade‐offs among high sensing performance, robust environmental stability, and scalable manufacturing. Here, we overcome these challenges by developing a flexible and self‐adhesive TE composite film through a scalable, all‐aqueous vacuum filtration of MXene, PEDOT:PSS, and waterborne polyurethane (WPU). This approach creates a unique “brick‐and‐mortar” nano‐architecture, where lamellar MXene nanosheets are cemented by a WPU matrix, conferring exceptional water impermeability and long‐term operational stability. Crucially, the electroactive bridging of MXene nanosheets by PEDOT:PSS establishes a uniform and efficient conductive network at an ultra‐low filler loading (3.3 wt%), supporting low‐cost manufacturing. Consequently, the resulting film delivers a compelling combination of universal self‐adhesion and high‐performance sensing, characterized by excellent temperature sensitivity, a rapid thermal response, and low electrical noise that enables a high resolution of 0.01 K, while maintaining stable operation even when submerged. This work offers a scalable strategy for high‐performance flexible TE sensors, enabling applications in intelligent material identification, underwater sensing, and human‐machine interaction.

Hydrogel fibers, which merge the inherent softness and biocompatibility of hydrogels with the high aspect ratio and flexibility of a fibrous structure, are highly sought after for next‐generation fibrous devices. However, their applications suffer from trade‐offs in mechanical robustness, environmental tolerance, and scalable production. Here, we introduce a synergistic freeze‐spinning and salting‐out strategy to overcome these intertwined challenges simultaneously. Freeze‐spinning aligns polyvinyl alcohol chains, enabling continuous production of oriented fibers. Subsequent salting‐out in sodium citrate/glycerol/H ₂ O solution synergistically enhances properties: citrate ions induce physical crosslinking to boost strength, orientation, and crystallinity, while glycerol provides freeze resistance and moisture retention. The resulting fibers exhibit an unattainable combination of ultrahigh elongation (1779.08 % ± 130.33 %) and tensile strength (20.50 ± 0.52 MPa), breaking through the performance boundaries of traditional hydrogel fibers. Furthermore, embedded silver nanowires endow the fibers with stable electrical conductivity and strain‐sensing even at −40°C. This work integrates ultra‐high strength, toughness, broad‐temperature environmental tolerance, and electronic functionality into a single hydrogel fiber, opening new avenues for high‐performance fibrous devices.

The continuous advancement of science and technology has led to the widespread application of nuclear technology across a diverse spectrum of fields, including scientific research, industrial processes, and particularly the medical domain for diagnostics and therapeutics. This proliferation, while beneficial, necessitates stringent protective measures for personnel who may be exposed to various forms of ionizing radiation, such as X-rays, γ-rays, and neutrons. In this context, polymer-based composite materials have emerged as a pivotal class of shielding solutions. These materials are typically fabricated by incorporating functional fillers—containing elements with high atomic numbers for photon attenuation or neutron-absorbing isotopes—into a continuous polymer matrix. This design strategy synergizes the processability and lightweight nature of polymers with the superior radiation shielding efficacy of the dispersed fillers, thereby offering robust and adaptable protection for individuals in nuclear-related occupations. This paper provides a comprehensive analysis of this material system. It begins by elucidating the fundamental attenuation and shielding mechanisms that govern the interaction of radiation with matter, establishing the theoretical foundation for material design. Subsequently, the paper offers a detailed review of the development history and recent research progress in polymer-based radiation shielding, tracing its evolution from conventional lead-impregnated rubbers to modern nanocomposites. The current research status of various material types is systematically summarized, highlighting technical achievements and innovative breakthroughs, such as the use of multi-layered structures or hybrid fillers. Furthermore, the paper analyzes the critical selection criteria for polymer matrices, considering factors like radiation resistance, thermal stability, and mechanical properties. Finally, it synthesizes the key challenges that remain to be addressed in current materials and provides a forward-looking perspective on future development directions, aiming to guide subsequent research and development efforts in this critical field.

Global water scarcity and pollution demand innovative solutions for sustainable clean water production. While interfacial solar evaporation holds great promise, current evaporators face significant challenges in achieving stable clean water productivity under harsh conditions. Here, a highly adaptive, liquid‐like, multifunctional Pickering emulsion solar evaporator is developed, which can be formed in situ on oil‐contaminated water or preconstructed with optimized rheological properties for flexible and scalable deployment. The resulting emulsion evaporator exhibits multidirectional water transport pathways, enhanced thermal localization, controllable salt deposition, and gravity‐assisted self‐cleaning capabilities. During operation, this evaporator can actively integrate oil contaminants into its emulsion structure without compromising efficiency, while inhibiting salt accumulation, realizing stable, long‐term ultrahigh‐rate evaporation (12.5 kg m ⁻² h ⁻¹ ) even in hypersaline (26 wt.%) conditions under elevated solar irradiation intensity (11 kW cm ⁻² ). It also degrades organic pollutants (e.g., nearly 100% phenol removal), deactivates bacteria, and prevents biofouling. Its phase transformation capability enables easy recovery and recycling, further enhancing practicality and sustainability. This study overcomes the limitations of conventional solid‐state solar evaporators, offering a versatile platform for clean water production in challenging environments.