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Metal–organic framework (MOF) materials are promising adsorbents for removing As(V) from sodium arsenate aqueous solutions, because of their high porosity and functional modulability. Two novel Pb(II) complexes {[Pb2(bcabsa)(μ2‐OH)]}n (Pb (bcabsa)) and {[Pb (Hbcabsa)]·(4,4′‐bpy)(H2O)}n (Pb (bcabsabpy)) (H3bcabsa = 4‐(N,N′‐bis(4‐carboxy benzyl)amino)benzene‐sulfonic acid, 4,4′‐bpy = 4,4′‐bipyridine), were hydrothermally synthesized. Pb (bcabsabpy) was characterized by single‐crystal X‐ray diffraction (SC‐XRD), X‐ray photoelectron spectroscopy (XPS), photoluminescence, powder X‐ray diffraction (XRD), and infrared radiation (IR) before and after the adsorption of As(V). In addition, the capacity of Pb (bcabsabpy) to remove arsenic was also investigated. The experimental results showed that Pb (bcabsabpy) had high stability within pH 4–12 and a relatively high As(V) removal rate (>90%) in the pH range of 4–10. The adsorption kinetics followed the pseudo‐second‐order kinetic model, whereas the adsorption isotherm was in agreement with the Langmuir equation. Pb (bcabsabpy) had a high adsorption capacity of As(V) in an aqueous solution (Qmax of 25.51 mg g−1). The fluorescence mechanism of the H3bcabsa, Pb (bcabsa), and Pb (bcabsabpy) are assigned to π‐π*, n‐π*, and π‐π* electron transition processes, respectively. [ABSTRACT FROM AUTHOR]

In this paper, a novel Yb metal–organic frameworks {[Yb(L)(DMA)(H2O)]·(3H2O)}n (Yb‐MOF, H3L is 4‐(N,N′‐bis(4‐carboxylbenzyl)amino)benzenesulfonic acid) was synthesized by solvothermal reaction. Modified Yb‐MOF was prepared by the potassium permanganate method for removing the Cu(II) and As(V) from simulated wastewater. The optimal pH value of modified Yb‐MOF for Cu(II) and As(V) adsorption was 5, and the optimal dosage of adsorbent was 0.04 mg/10 ml by static adsorption test. Four isothermal adsorption models (Freundlich, Langmuir, Temkin, and Dubinin–Radushkevich models) were fitted and analyzed. The adsorption processes of Cu(II) and As(V) were consistent with Freundlich, Langmuir, and Temkin models. The highest Cu(II) and As(V) adsorption capacity are 59.418 and 81.169 mg/g, respectively. The adsorption kinetic model and thermodynamic analysis of the modified Yb‐MOF for Cu(II) and As(V) were studied. The results showed revealed that the pseudo‐second‐order kinetic had a higher correlation association with the Cu(II) and As(V) adsorption process, indicating that chemisorption was dominant in both processes. At 298 and 308 K, the Cu(II) and As(V) adsorption by modified Yb‐MOF is spontaneous. [ABSTRACT FROM AUTHOR]

Four iron(II) carbonyl complexes, fac‐[Fe (CO)3X2(py)] (X = I−, 1 and Br−, 3), fac‐[{Fe (CO)3X2}2(bipy)] (X = I−, 2 and Br−, 4), were facilely synthesized by reacting cis‐[Fe (CO)4X2] (X = I−, Br−) with pyridine (py) and 4,4′‐dipyridine (bipy) ligands, respectively, in good yields (70%~85%). These complexes were fully characterized, and the structures of Complexes 2 and 3 were crystallographically analyzed. In dimethyl sulfoxide, they decomposed rapidly to release carbon monoxide (CO), and in methanol, they showed better stability which allowed kinetically analyzing their decomposing behaviors. The self‐decomposing in methanol fitted first‐order kinetics with a half‐time ranging from several minutes to 1 h. Our results suggested that the ligand with great conjugation (bipy) and strong electron‐donating capability (iodide) could stabilize the iron(II) carbonyl complexes. The decomposition of the iodo complexes (1 and 2) involved the production of iodine radicals. MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide) assessments revealed that the efficacy against human bladder carcinoma cell line (RT112) is in the following trend: 1 > 2 > 3 > 4. The relatively strong efficacy of Complexes 1 and 2 is mainly contributed to the in situ generated iodine radicals. The combination of the cytotoxicity of the in situ generated radicals with the anticancer activity of CO as reported in literatures may lead to developing novel anticancer drugs with enhanced efficacy. [ABSTRACT FROM AUTHOR]