Search

Summary The capture of radioiodine species during nuclear fuel reprocessing and nuclear accidents is crucial for nuclear safety, environmental protection, and public health. Previously reported emerging materials for iodine uptake cannot outperform commercial zeolites and active carbon under the practical dynamic scenario. Herein, we present a new design philosophy aiming at significantly enhanced specific host-guest interactions and obtain a nitrogen-rich covalent organic framework material by introducing a bipyridine group into the building block for the simultaneous capture of both iodine gas through enhanced electron-pair effect and organic iodide via the methylation reaction. These efforts give rise to not only an ultrahigh uptake capacity of 6.0 g g−1 for iodine gas and a record-high value of 1.45 g g−1 for methyl iodide under static sorption conditions but also, more importantly, a record-high iodine loading capability under dynamic conditions demonstrated from the breakthrough experiments.

Polymers with aggregation-induced emission (AIE) characteristics have attracted much attention because of their potential applications in luminescent self-assembling, anti-counterfeiting, decoration, and photoelectric devices. To date, most technologies to prepare fluorescent polymers lack versatility; moreover, the resultant material exhibits intrinsic defects of poor fluorescence intensity and durability. Herein, we covalently anchored units of tetraphenylethylene (TPE), an archetypal AIE luminogen, on the surface of conventional polymer fibers such as polyethylene/polypropylene nonwoven fabric (PE/PP NWF) via radiation-induced graft polymerization (RIGP) and subsequent chemical modification for the first time. The physicochemical properties of the original and modified fabrics were characterized in detail by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), wide-angle X-ray diffraction (WAXD), and thermogravimetric analysis (TGA). The results indicated that the TPE units were covalently and uniformly anchored on the surface of PE/PP NWF with a disordered architecture and that the as-prepared fluorescent fabric had a high thermal stability. Additionally, the fluorescent properties of the as-prepared fluorescent fabric were measured. It emitted a strong green emission and showed superior fluorescence durability after 20 cycles of accelerated laundering or in 12 M concentrated HCl and NaOH solutions.

It is still a challenge that directly reducing the uranium concentration of wastewater or radioactive wastes by adsorption to or below the criterion (30 ppb), especially from the system of low uranium concentration due to weak affinity and bad collection. Herein we have successfully introduced hydroxypyridone (HOPO) groups onto polyethylene nonwoven fabric (PENWF) surface denoted as PENWF-HOPO by radiation graft technology and follow-up two-step chemical reactions to deeply remove uranium from low-concentration (500 ppb) aqueous solutions. The chemical structures, surface morphologies, and thermal stabilities of the original and modified PENWF were characterized in detail by FT-IR, XPS, SEM, and TGA, with the results indicating successful preparation and good thermal stability of the adsorption material used under ambient conditions. Batch adsorption results show that the adsorbent removes the uranium almost completely within 12 h in a wide pH (3–10) range, and the adsorption obeys the Langmuir isotherm. Desorption and regeneration confirms its excellent regeneration and reusability (5 cycles). Importantly, this adsorbent could efficiently remove uranium (more than 97% removal ratio) from diluted aqueous solution, in which contains a serial of competing metal ions (La3+, Cr3+, Ba2+, Mn2+, Pb2+, Ni2+, Co2+, Cu2+, Zn2+, Sr2+, Cs+) or high NaF, Na2SO4, and NaH2PO4 concentrations (40 g/L).

A new macroporous ZnO/MoO 3 /SiO 2 hybrid was synthesized by a method involving sol–gel technology and biomimetic synthesis. It was characterized by Elemental analysis, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS) and scanning electron microscopy (SEM). Chemical degradation of 0.3 g/L Safranin T (ST) by air oxidation over macroporous ZnO/MoO 3 /SiO 2 hybrid was studied. It was found that the decolorization efficiency and the chemical oxygen demand (COD) removal of ST reached above 95.3% and 93.2%, respectively, within 25 min at room temperature and atmospheric pressure. And the organic pollutant was mineralized to simple inorganic species such as HCO 3 − , Cl − and NO 3 − , while the total organic carbon (TOC) decreased 95.4%. The structure and morphology of the catalyst were still stable after six cycling runs and the leaching test showed negligible leaching effect.