SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3803-8
The molecular copolymerization of donor-acceptor (D-A) interactions has been effectively utilized to modulate the charge transfer dynamics in polymeric carbon nitride (PCN) photocatalysts. Herein, a D-A configured photocatalyst (TPCN) was constructed by copolymerizing 4,4’,4’’-(1,3,5-triazine-2,4,6-triyl) trianiline (TAPT) as the electron donor with triazine units (electron acceptor). The unique propeller structure of TAPT, combined with the triazine framework, expanded the π-conjugated system and induced a strong built-in electric field (BIEF) across the D-A configuration. Theoretical calculations and transient absorption spectroscopy revealed that this synergistic effect facilitated intramolecular charge separation and widened the range of light absorption, indicating accelerated charge transfer and suppressed recombination in TPCN. The optimized TPCN3 sample exhibited dramatically enhanced photocatalytic H2O2 production (1.74 mmol g−1 h−1), representing a 13.4-fold increase over pristine PCN. Additionally, the TPCN3 sample also exhibited significantly faster degradation kinetics than PCN counterpart toward various emerging contaminants. This work demonstrates a promising strategy for designing efficient metal-free photocatalysts for sustainable H2O2 production and environmental remediation.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025031304
The Qingling River, a representative silicate rock catchment in the upper Yangtze Basin, is vital for agricultural productivity in central Yunnan. To investigate its hydrochemical characteristics, river water samples were systematically collected during both dry and wet seasons. Employing hydrochemical diagrams, statistical analysis, and absolute principal component score-multiple linear regression (APCS-MLR) modeling, we identified influencing factors and their contributions to water chemistry and evaluated irrigation suitability. Results showed that pH ranged from 7.36 to 9.18 in dry season and 7.12 to 8.92 in wet season, with total dissolved solids (TDS) varying between 119–2684 mg·L−1 and 125–2342 mg·L−1, respectively. Dominant cations were Ca2+ and Na+, while anions were primarily SO4^2− and HCO3^− in both seasons; notably, SO4^2− concentrations significantly exceeded the Yangtze River Basin’s average. Hydrochemical types varied seasonally: HCO3·SO4-Ca·Mg and HCO3·SO4-Ca dominated in dry season, whereas HCO3·SO4-Ca·Na, HCO3·SO4-Ca·Mg, and HCO3-Ca prevailed in wet season. The river water was affected by five factors: sulfuric acid-dominated water-rock interactions, carbonic acid-dominated water-rock interactions, domestic sewage discharge, agricultural non-point source pollution, and unknown sources. Contribution rates were 47.90%, 24.80%, 16.98%, 2.40%, and 7.92% in dry season, and 28.23%, 28.94%, 27.48%, 2.02%, and 13.34% in wet season, respectively. Water-rock interactions emerged as the primary control on hydrochemistry. While most samples were suitable for irrigation, a few exhibited high salinity, warranting cautious use. This study provides scientific support for irrigation water resource management and safe utilization in the Qingling River Basin.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4016-3
Rare earth-based electromagnetic wave (EMW) absorbing materials are promising due to their strong dielectric and magnetic loss capabilities, yet effective enrichment and utilization of rare earth ions remain challenging. Here, an anionic imidazolium-based metal-organic framework (MOF), MOZ-200, is employed to enrich multiple rare earth ions (La3+, Ce3+, Pr3+, Nd3+, Y3+) via host-guest interactions. The anionic framework uniformly confines these ions, which are converted in situ into highly dispersed high-entropy rare earth alloy nanoparticles during carbonization. The resulting HE@C composites feature a conductive, graphitized carbon matrix with abundant multi-scale polarization centers and heterogeneous interfaces, enhancing dipole polarization, interface polarization, and conductive loss. Consequently, the material achieves excellent EMW absorption in the Ku band, with a minimum reflection loss of -79.20 dB and a maximum effective absorption bandwidth of 5.23 GHz. Integrated into a polyurethane matrix, a multifunctional flexible device is realized, offering EMW absorption, photothermal heating, microwave de-icing, and hydrophobicity. This work provides a feasible strategy for rare earth ion utilization and advances the design of flexible multifunctional EMW absorbing materials.