Materials Horizons最新文献

Seawater splitting has emerged as a promising alternative to overall water splitting because it eliminates the kinetically sluggish oxygen evolution reaction (OER), which is a bottleneck in water splitting, and avoids the low economic value of O₂. Moreover, in seawater splitting, H₂ evolution coupled with the oxidation of chloride (Cl^-) to value-added chlorine (Cl₂) and/or hypochlorous acid (HOCl) can simultaneously benefit the energy and environmental sectors. Cl₂ and HOCl are widely used for bleaching, disinfection, sanitisation and sterilisation in the medical sector and for purifying drinking water and water in swimming pools owing to their strong oxidising and antibacterial properties. Mainstream industrial production employs the chlor-alkali electrolysis of sodium chloride (NaCl), which requires significant energy input and releases enormous amounts of CO₂. To achieve the sustainable production of Cl₂ and HOCl while reducing energy consumption and environmental impacts, photocatalytic (PC) and photoelectrochemical (PEC) technologies have been employed as green alternatives. Importantly, PC and PEC enable the on-site production of Cl₂/HOCl in remote areas, which can circumvent their instability (decomposition), storage and transport issues. This article reviews the recent progress in the PC and PEC production of Cl₂/HOCl, along with the catalytic materials used and their designs and photocatalytic performance. The applications of in situ HOCl production in anti-bacterial treatment, ammonia removal, the selective oxidation and conversion of organic compounds, and CO₂ conversion are discussed. We also address the challenges in this area and highlight prospects for future research directions. Overall, we demonstrate that the PC and PEC production of Cl₂/HOCl serves as a green and sustainable alternative to the chlor-alkali process. This research area is still in its infancy, and we hope that this review article will garner the attention of researchers to contribute to this area, leading to a step closer toward practical applications.

Freshwater harvesting is an important strategy to address water scarcity and provide a sustainable solution to such global challenges. In recent years, nanostructure-doped polymer hydrogels (NSPHs) have gained popularity as advanced materials with promising capabilities for effectively enhancing fog-harvesting performance due to their desirable structural, thermal, and surface features. Fog harvesting is an important technique for freshwater collection. This review discusses the progress in fog harvesting; including material innovations, structural design, mechanistic understanding, hydrogel principles, challenges, and advancements in NSPHs.The aim of this study is to provide a comprehensive framework for novel applications in promising research areas, establishing nanoparticle-doped polymer hydrogels as next-generation sustainable fog-harvesting materials. Nanoparticles enhance surface wettability, nucleation sites, surface-to-volume ratios, flexibility, thermal conductivity, solar absorption, and directional water transport, enabling the application of these composites in sustainable agricultural practices, renewable energy production, and smart water management. The study concludes by identifying key research gaps in advanced material performance, scalability, and sustainability on a local scale; intelligent hydrogel-based nanocomposite systems will ultimately address the implications of global water scarcity through fog harvesting.

The strategic engineering of B-site cations in Sillén-Aurivillius perovskite oxyhalides unlocks unprecedented control over electronic structure and polarization effects: yet their potential for mechano-driven catalysis remains unexplored. Herein, a novel double-layer perovskite oxyhalide, Bi₅Ti₂O₁₁Cl, was theoretically predicted using density functional theory (DFT) and successfully synthesized for the first time using a molten-salt method. DFT analysis revealed a predominantly O-2p orbital character at the valence band maximum (VBM)-distinct from Br/I-analogs with halide-p contributions near the VBM. This distinctive electronic structure provides exceptional stability against hole-induced degradation while enabling remarkable charge separation efficiency. The material's asymmetric [BiTi₂O₇] perovskite architecture creates intense ferroelectric polarization through lattice distortion, generating a powerful built-in piezoelectric field that drives charge separation. These synergistic effects yield a record-breaking piezocatalytic H₂O₂ production rate of 15 041.41 µmol g^-1 h^-1 under visible light irradiation-a 210.84-fold improvement over conventional photocatalysis, achieved without sacrificial agents. These findings establish a new paradigm in ferroelectric material design, combining computational prediction, structural innovation, and exceptional catalytic performance for sustainable chemical production.

As a zero-carbon way to produce hydrogen, traditional water electrolysis is hindered by the sluggish kinetics of the oxygen evolution reaction (OER), which results in a high voltage input. Hybrid water electrolysis (HWE), which replaces the OER with economically viable electrooxidation reactions, could significantly lower the required voltage and, in turn, enhance energy conversion efficiency. Moreover, HWE could be integrated with certain existing industrial processes in principle; however, the feasibility and cost impact depend on substrate availability, product separation/purification, and long-term system durability. This review systematically categorizes three major types of alternative oxidation reactions based on their reaction mechanisms and products: conversion reactions (targeting the selective transformation of valuable substrates), degradation reactions (aimed at breaking down pollutants or hazardous compounds), and hydrogen carrier oxidation reactions (utilizing hydrogen-rich compounds such as ammonia to facilitate energy conversion). The economic feasibility, environmental benefits and relevant catalyst design strategies of these reactions are also explored. Finally, it summarizes the current research status of hybrid water electrolysis and discusses the challenges encountered, as well as prospects for development.

The design of charge-trapping sites is the basic and critical factor to explore organic photomultiplier phototransistors and synaptic transistors. There are few examples of charge trapping achieved directly by constructing dielectric materials, as the traditional view holds that their wide band gaps make charge trapping and release difficult. This work employs the liquid phase epitaxy method to construct a two-dimensional confined dielectric MOF-199 island-like film with a 20 nm diameter as the dielectric layer of bulk heterojunction-based photo/synaptic transistors. Diverse energy level structures of metal complex nanostructures integrated intrinsic charge-trapping sites with multi-channel electron and energy exchange to the active layer. The multi-channel exchange combines the response advantages of machines and the human brain, while the intrinsic charge trapping avoids interface charge quenching. It demonstrates simultaneous high photocurrent and good long-term plasticity, a high phototransistor performance of photo-responsivity R = 650.1 A W^-1/specific detectivity Jones, and efficient photonic synaptic transistors with maximum paired-pulse facilitation index of 142% and single-pulse remaining ratio of 65%. All these results point to the organic phototransistors for emulating the functions of biological synapses, which indicate their potential as the building blocks of bionic electronic circuit systems.

With the growing demand for miniaturizing nonlinear on-chip integrated devices, enhancing the nonlinear optical responses of two-dimensional (2D) materials is essential. However, due to their atomic scale, nonlinear optical processes such as second-harmonic generation (SHG) and Raman scattering are generally weak. To enhance these nonlinear signals and improve inspection accuracy, we developed an air-gap-suspended nanocavity structure. This design effectively enhances the nonlinear optical response while minimizing substrate disturbance, facilitating the precise characterization of 2D materials. We achieved significant broadband electric field enhancement by employing optical thin-film theory and three-dimensional finite-difference time-domain (3D-FDTD) simulations to optimize the interference and cavity effects of the nanocavity. As a result, SHG and Raman signals of 2D materials were dramatically enhanced. Specifically, the SHG signals of distinct 2D materials suspended on a nanocavity were enhanced over 13 000 times, while the Raman signals were enhanced over 580 times. Moreover, polarization-resolved SHG measurements revealed a significant depolarization effect in the 2D materials after varying laser treatment durations. This observation suggests that the degree of SHG polarization anisotropy can serve as a practical indicator for assessing the quality of 2D materials. The air-gap-suspended nanocavity structure not only provides substantial signal enhancement but also serves as an excellent platform for studying the intrinsic properties of distinct 2D materials.

Membrane-based CO₂ separation is emerging as a central technology for achieving carbon neutrality, yet its widespread deployment remains constrained by longstanding trade-offs among permeability, selectivity, long-term stability, and scalability. This review provides the conceptual foundations, materials evolution, and market drivers shaping the next generation of polymeric CO₂ separation membranes. We first revisit the fundamentals of mass transport through dense polymer films and highlight how trade-offs arise from the interplay among solubility, diffusivity, and free-volume architecture. Building on this framework, we examine three major materials platforms that have redefined performance boundaries: thermally rearranged (TR) polymers that generate controlled microporosity through in situ cyclization; polymers of intrinsic microporosity (PIMs) that embody rigid, contorted backbones with permanent ultramicroporosity; and ether-rich CO₂-philic polymers that achieve high solubility selectivity and excellent processability. By integrating molecular-level insights with thin-film engineering considerations, we evaluate each material family's potential and limitations in realistic process environments. At the system level, we analyze global markets, including natural gas sweetening, post-combustion CO₂ capture, blue hydrogen purification, and biogas upgrading, where polymeric membranes are poised for rapid growth. Finally, we identify future research directions centered on stabilizing free volume, suppressing plasticization, enhancing thin-film robustness, and accelerating materials-to-module translation through digital design and advanced fabrication. Together, these strategies delineate a pathway for polymeric membranes to become scalable, energy-efficient tools for industrial CO₂ management in the coming decade.

3D printing is emerging as a transformative approach in functional materials fabrication, enabling precise control over structural parameters, offering opportunities to custom-design permeability, selectivity, and fouling resistance of membrane materials. The ability to fabricate membranes with near-isoporous pore size distribution further enhances their potential for advanced separation applications. The development of formulation and engineering solutions to support the formation of nanoporous nanocomposites with extremely accurate control over the nano-additives distribution is demonstrated in this study with the incorporation of Zinc phthalocyanine (ZnPc), a visible-light-responsive photosensitizer, to offer reactive oxygen species (ROS)-mediated photodynamic inactivation. This study introduces the development of 3D-printed microfiltration membranes, integrating engineered pore structures with photodynamically active surfaces to enhance filtration and antimicrobial performance. Morphological characterization revealed a structural evolution from globular to sheet-like and rod-like formations, significantly influencing pore size, wettability, and surface charge. Photodynamic assessments validated efficient ROS generation, enhancing methylene blue degradation and E. coli inactivation under irradiation. Filtration trials confirmed ZnPc-enhanced bacterial rejection and biofouling resistance, with the 2 wt% ZnPc membrane achieving 99.5% E. coli rejection under irradiation. Furthermore, virus filtration experiments confirmed the efficacy of 1 wt% ZnPc membrane, achieving a 2.56-log, or 99.72%, reduction in Influenza A virus (IAV) recovery. These findings demonstrate that 3D-printed ZnPc-functionalized membranes offer a dual-function approach, combining precise structural control with photodynamic antimicrobial activity, making them promising candidates for next-generation, light-assisted water treatment systems.

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Achieving aerogel fibers that combine high porosity with mechanical robustness under ambient drying remains a long-standing challenge. Here, we present a proton-donor-assisted solvent-exchange strategy to fabricate hierarchically porous aramid nanofiber (ANF) aerogel fibers with 85.2% porosity and ultrahigh toughness (>9.3 MJ m^-3). A suite of characterization and molecular dynamics simulations reveal that restoring hydrogen bonding between ANFs requires both reprotonation of poly(p-phenylene terephthalamide) and a nonpolar solvent environment to promote close chain packing. Introducing trace proton donors (e.g., water or citric acid) during solvent exchange is therefore essential to strengthen hydrogen bonding and stabilize ANF networks against capillary collapse. Furthermore, spatial heterogeneity in solvent composition, arising from proton-donor-induced solvent-solvent phase separation, creates a hierarchical pore architecture that enables multimodal mechanical energy dissipation, yielding simultaneously high tensile strength (>19.7 MPa) and unprecedented stretchability (>82%). The aerogel fiber-based textiles exhibit outstanding thermal insulation and resilience across cryogenic to high temperatures, offering a scalable pathway toward next-generation thermal-protective and impact-resistant aerogel textiles.