SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3702-0
Construction of metal-mediated redox sites is an appealing approach to enhance photocatalytic CO2 reduction coupled with H2O oxidation. However, conventional static redox sites generally lack spatiotemporal matching during reaction processes due to the constraints of rigid structure and the linear scaling relationship of adsorbed species. Herein, an alkanolamine-Ir synergistic system was developed, where flexible monoethanolamine (MEA) molecules function as molecular ferries to selectively adsorb CO2 via carbamate formation, while adjacent Ir nanoparticles (NPs) serve as H spillover hubs that relay protons, creating spatiotemporal adaptability that synchronizes CO2 reduction and water oxidation. In addition, time-resolved in situ spectroscopy directly captures the rapid transformation of carbamate intermediates concurrent with sustained IrOOH intermediates formation. Microkinetic modeling further demonstrates that the MEA-Ir modified system (M-Ir/ACN) creates interconnected H spillover networks between Ir NPs and MEA, facilitating efficient proton transport that drives *COOH formation with a favorable thermodynamic energy. As a result, the M-Ir/ACN achieves a 20-fold increase in CO production compared to the pristine sample while maintaining high stability throughout 45 h of continuous operation. This study presents that flexible molecular ferries boost CO2 adsorption, and deciphers how flexible molecular-metal synergy directs the trafficking of CO2-derived intermediates toward highly efficient CO2 photoreduction.
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.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025011804
Per- and polyfluoroalkyl carboxylic acids (PFCAs) are persistent organic pollutants whose isomers exhibit distinct environmental behaviors, bioaccumulation potentials, and toxic effects due to structural variations. Accurate identification of PFCA isomers is critical for risk assessment and pollution control, yet existing detection methods predominantly rely on standard references, posing challenges for precise analysis of isomers with subtle structural differences. Single-molecule electrochemical sensing via nanopores offers a standard-free approach by correlating molecular volume with current blockade, but its capability to distinguish PFCA isomers remained unverified. This study targeted three sets of PFCA isomers: 4,5,5-trifluoropent-4-enoic acid vs. 4,4,4-trifluoro-3-methylbut-2-enoic acid; 3,3,3-trifluoro-2-methylpropanoic acid vs. 4,4,4-trifluorobutanoic acid; and 2-(trifluoromethoxy)acetic acid, 3,3,3-trifluorolactic acid, and (2R)-3,3,3-trifluoro-2-hydroxypropanoic acid. By engineering nanopore interfaces (WT, R220N, R220Q Aerolysin) and extracting multi-dimensional characteristic parameters, the method achieved near 100% accuracy in identifying all seven isomers. Feature selection further enabled high classification accuracy with low data volumes, laying the foundation for rapid single-molecule detection of PFAS and other emerging contaminants.