SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4267-y
The synthesis of two-dimensional MBenes from MAB-phase ceramics is impeded by uncontrolled etching kinetics that compromise structural integrity and yield. This study introduces a vacuum molten salt strategy to regulate space-charge accumulation during the selective removal of Al from Mo2AlB2, producing honeycomb-like architectures. The vacuum environment suppresses oxidative side reactions and modulates ionic transport, enabling precise control over etching depth and morphology. The resulting Mo2AlB2 exhibits exceptional electromagnetic wave absorption, with a minimum reflection loss of -56.3 dB at 2.4 mm and an effective absorption bandwidth of 6.8 GHz. These metrics surpass conventional etching-derived MBenes by a factor of 2.5 in attenuation capacity. The space-charge-regulated mechanism is elucidated through in situ spectroscopic and computational analyses, revealing that vacancy-induced charge redistribution governs the etching front propagation. This work establishes a scalable route for high-purity MBenes with tailored porosity, addressing critical bottlenecks in energy absorption and catalytic applications. The vacuum molten salt approach eliminates the need for hazardous HF, offering a safer and more environmentally benign pathway for industrial translation.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4309-8
Iridium-doped cobalt oxide nanosheets derived from a ZIF template were evaluated as oxygen evolution reaction (OER) catalysts for proton exchange membrane water electrolysis (PEMWE). Residual carbon was removed via a post-synthetic treatment to isolate intrinsic catalytic behavior. The Ir0.23Co0.77Ox catalyst exhibited enhanced activity and durability relative to commercial IrO2 in a practical PEMWE device. Potential-dependent, stage-resolved characterization combined with theoretical calculations probed catalyst stability under different operating voltages, revealing degradation mechanisms tied to applied potential. Contact angle measurements showed that the Ir0.23Co0.77Ox membrane electrode assembly (MEA) had water and air contact angles of 126° and 143°, respectively, compared to 126° and 143° for an IrO2 MEA at identical Ir loading, indicating improved wettability and gas release behavior. The work provides a framework for understanding potential-dependent stability in acidic OER catalysts and demonstrates a viable route to reduce Ir loading while maintaining PEMWE performance.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4183-3
Excessive ultraviolet (UV) radiation poses significant risks to human health, necessitating highly sensitive detection systems. Organic photodetectors (OPDs) offer high sensitivity and tunable spectral response, but their UV performance is constrained by conventional glass/indium tin oxide (ITO) substrates and electrodes, and insufficient photoactive layer responsivity. Here, we report high-performance UV-OPDs achieved through UV-transparent window and active-layer optimization. Replacing glass/ITO with a UV-transparent window comprising a quartz substrate and PH1000 electrode enhances UV transmittance. Integrating the high UV-responsive blend PM6:Y6:PC71BM as the active layer, the optimal ternary UV-OPD exhibits external quantum efficiency (EQE) exceeding 53% across 280–400 nm, with a peak EQE of 78.29% and responsivity of 214.68 mA/W at 340 nm, alongside a rapid response time of 2.6/2.1 μs. This performance represents the best combination of responsivity and response time reported to date in the UV region. We demonstrate the potential of these UV-OPDs for outdoor real-time UV monitoring. This work presents a promising strategy for developing high-performance UV-OPDs through transparent substrate and electrode engineering, and active-layer optimization.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3887-6
The proliferation of 5G/6G communications and radar systems has intensified electromagnetic wave (EMW) leakage, interference, and thermal management challenges. This study presents a 3D MXene sponge/NiFe@NC heterostructure with tunable pore architecture, fabricated by pyrolyzing a polyurethane (PU) foam template uniformly coated with NiFe-decorated Ti3C2Tx MXene nanosheets. The resulting porous dielectric-magnetic network integrates interconnected MXene pathways with uniformly dispersed NiFe@NC nanoparticles, enabling synergistic dielectric-magnetic loss via conduction loss, dipole/interface polarization, and magnetic loss. Precise pore structure design enhances impedance matching and promotes multi-scattering and internal reflection of EMWs. An 'EMW-pore matching' mechanism is proposed, where pore size governs impedance matching at specific frequencies, enabling tunable absorption performance. The optimized absorber achieves a reflection loss (RL) of -67.84 dB, while radar cross-section (RCS) simulations confirm exceptional attenuation and stealth potential. Additionally, the 3D skeleton derived from PU foam confers remarkable thermal resistance and flame retardancy. This pore-regulation strategy provides a scalable route to designing lightweight, broadband, and thermally stable EMW absorbers for next-generation communication and stealth applications.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202506020
The rotary kiln roasting of lepidolite for lithium extraction faces challenges of unstable lithium conversion rates and high energy consumption. To address this, a multi-objective optimization method coupling improved neural network simulation with a multi-objective genetic algorithm was proposed, targeting the synergistic optimization of lithium conversion rate (TRLi) and natural gas consumption intensity (EIng). Using long-term industrial time-series data of batching parameters and kiln operating variables, back-propagation (BP) neural network and its particle swarm optimization (PSO) improved variant were developed to model TRLi and EIng. The PSO-BP model demonstrated superior accuracy in capturing the complex nonlinear relationships, reducing mean absolute percentage errors (MAPE) to 0.278 and 0.284 for TRLi and EIng, respectively. Subsequently, the non-dominated sorting genetic algorithm II (NSGA-II) was employed to construct a multi-objective optimization model, yielding a Pareto-optimal set of process parameters that maximize TRLi and minimize EIng. The results revealed that under NSGA-II optimized conditions, TRLi could be stabilized between 82.45% and 87.96%, an average increase of 3.61 percentage points over baseline operations, while EIng could be reduced to 53.7 m3 per ton of clinker. For an annual processing capacity of 3.2×105 tons of lepidolite concentrate and sulfate mixture, this corresponds to an additional 127.1 tons of lithium metal recovery, a reduction of 1,964,912 m3 in natural gas consumption, and a decrease of 3,763.84 tons in CO2 emissions annually. This study provides theoretical and technical support for the green, high-quality, and low-carbon supply of critical raw materials for the lithium battery new energy industry.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3646-1
Repairing cartilage defects requires biomaterials with mechanical properties similar to native cartilage. However, balancing these properties with biodegradability remains a major challenge. In this study, a degradable antibacterial hydrogel with promising mechanical characteristics was developed for personalized cartilage defect repair. The hydrogel was synthesized using chitosan and gelatin via microcrystallization and gelation, combined with chemical crosslinking facilitated by epichlorohydrin. This method significantly enhanced the mechanical properties of the material, with compressive modulus of the optimal group reaching 0.2 MPa and tensile strength reaching 2.2 MPa, which are comparable to those of human cartilage. The hydrogel maintained its integrity after 50000 compression cycles. With excellent flowability prior to crosslinking, it can adapt to complex cartilage defects. The inclusion of gentamicin provides antibacterial properties, while nano-hydroxyapatite promotes osteogenesis. This hydrogel, with its multiple crosslinking mechanisms, balances mechanical strength, biodegradability, and adaptability, offering a promising solution for repairing infected cartilage defects.
Journal of Fuel Chemistry and Technology•2026•DOI: 10.1016/S1872-5813(26)60640-8
Ethylene (C2H4) in vehicle exhaust is a highly reactive volatile organic compound (VOC) whose photo-oxidation with NOx contributes to the formation of O3 and secondary organic aerosols (SOA), a key precursor of PM2.5. This study designs a novel MgO-supported Ag-Cu bimetallic catalyst and investigates its performance using density functional theory (DFT). The effects of Ag and Cu loading on geometric structure, stability, and reactant adsorption are analyzed, and the catalytic oxidation pathways of C2H4 over AgCu-MgO are elucidated. Results indicate that loading Ag significantly enhances C2H4 adsorption, with a maximum adsorption energy of -1.46 eV, while O2 adsorption remains weak (-0.45 eV). Cu-MgO shows moderate C2H4 adsorption (-0.87 eV at bridge site) but higher O2 adsorption (-0.76 eV). Among 17 AgCu-MgO dual-atom catalyst (DAC) configurations, those with Ag and Cu co-adsorbed at Mg sites are thermodynamically more stable (binding energies below -10 eV). Configurations with Ag and Cu in close proximity enhance co-adsorption of C2H4 and O2. C2H4 oxidation preferentially proceeds via C=C bond cleavage to form *CH3 and CO2. For three representative configurations (1, 3, 6), free energy barriers for rate-limiting steps in the *HCO and CH2O pathway are consistently higher than those for *CH3 and CO2 pathway. Configuration 6 exhibits the lowest energy barrier (0.32 eV) for its rate-limiting step, indicating the highest catalytic performance. This study provides atomic-scale insights for rational design of efficient catalysts targeting olefinic pollutants in automotive emissions.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2026021301
Lithium cobalt oxide (LCO) nanoparticles (NPs), generated during the lifecycle of LCO batteries via mechanical wear, pose respiratory health risks. This study systematically assessed LCO NPs' physicochemical properties, ion release, and immunotoxicity using multi-scale models. LCO NPs exhibited irregular morphology, layered crystal structure, good dispersion, and negative surface charge. Cobalt ion release was minimal: 1.03% in deionized water and 0.11% in cell culture medium. In vitro, LCO NPs significantly induced reactive oxygen species (ROS) production and secretion of pro-inflammatory cytokines (IL-6, IL-1β, TNF-α) in macrophages, promoting M1 polarization. In vivo, intranasal exposure caused dose-dependent pulmonary accumulation, alveolar destruction, inflammatory cell infiltration, and elevated cytokines in bronchoalveolar lavage fluid (BALF). Transcriptomic analysis revealed significant enrichment of NF-κB, JAK-STAT, and Toll-like receptor signaling pathways, implicating these in macrophage activation and inflammation amplification. This multi-level study elucidates LCO NPs' immunotoxicity mechanisms, providing a scientific basis for environmental health risk assessment and management of lithium-ion battery materials.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4107-x
Aqueous fiber zinc-iodine batteries (FZIBs) with four-electron redox exhibit inherent safety and high energy density for wearable electronics. Nevertheless, their practical implementations are hindered by unsatisfactory cycling stability and low realistic energy density, mainly caused by severe H2O-induced nucleophilic attack toward iodine species and poor zinc anode reversibility. Here, we report a quaternary ammonium-mediated coordination strategy to simultaneously address the irreversible cathode/anode redox behavior and thus promote the electrochemical performance of four-electron FZIBs. The cationic choline ion (Ch+) induces complexation with ICl2− via electrostatic interaction, homogenizing the electron cloud density and suppressing irreversible hydrolysis of I+ species, enabling a reversible near-theoretical high capacity of 418.3 mAh g−1. Meanwhile, preferentially adsorbed Ch+ on the zinc anode surface creates positively charged shielding layers, mitigating the tip effect caused by localized electric field and achieving robust zinc stripping/plating. The enhanced cathode/anode reversibility and improved interfacial stability enable stable FZIBs operation for over 20,000 cycles at 20.0 A g−1. Moreover, successful integration of FZIBs into electronic textiles with glucose and cardiac rhythm sensors demonstrates great potential for next-generation wearable electronics.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3971-6
Photocatalytic reduction of soluble U(VI) to insoluble U(IV) is a pivotal technology for uranium remediation and resource recovery. However, conventional covalent organic frameworks (COFs) suffer from short-range electron transport, leading to rapid electron-hole recombination and limited efficiency. Here, we report the rational design of anthraquinone-based COFs with donor-acceptor (D-A) architectures, employing 2,4,6-triformylphloroglucinol (TP) as the donor and 1,4-diaminoanthraquinone (1,4-DQ) or 1,5-diaminoanthraquinone (1,5-DQ) as the acceptor. By varying the connection mode of the building units, the electron transfer distance is systematically extended, effectively suppressing charge recombination. Among the synthesized COFs, ECUT-COF-152 exhibits optimal photocatalytic activity under visible light, achieving 100% U(VI) removal with a maximum reduction capacity of 1950 mg g−1. This work demonstrates that precise tuning of the D-A structure and electron transfer pathways is an effective strategy to enhance the photocatalytic performance of COFs for uranium reduction, offering insights for the design of efficient materials for nuclear waste treatment.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4099-2
Lithium (Li)-metal batteries (LMBs) are promising next-generation energy storage systems due to their high theoretical capacity (3860 mAh g−1) and low electrochemical potential (−3.04 V vs. standard hydrogen electrode). However, uncontrollable Li dendrite growth and volume fluctuations during cycling cause low Coulombic efficiency, safety hazards, and rapid capacity decay. Conventional 3D current collectors mitigate these issues by increasing surface area and providing void space, but they suffer from top-heavy deposition and underutilization of internal space. Emerging Janus/gradient anode structures, featuring asymmetric or gradient properties in lithiophilicity, conductivity, or porosity, enable bottom-up Li plating and efficient space utilization. This review systematically summarizes design principles, operational mechanisms, and recent progress in lithiophilic-lithiophobic Janus designs, conductivity-gradient frameworks, and dual-gradient configurations. These structures collectively improve Coulombic efficiency, cyclic longevity, and safety. The review concludes with future research directions, underscoring the potential of Janus/gradient anodes for high-energy-density and durable LMBs.