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Here, a novel Mg/Al-layered double oxide (MgAl-LDO) with a flower-like architecture was synthesized through facile green co-precipitation and calcination methods for phosphate separation and recycle from wastewater. The as-prepared MgAl-LDO demonstrated high specific surface area of 200.17 m2/g based on its 3D hierarchical flower-like structure. The phosphate adsorption was well conformed to Pseudo-second-order kinetic model and Langmuir model, suggesting a homogeneous monolayer chemisorption with a maximum adsorption capability of 103.61 mg P/g. The existence of Cl−, NO 3 − ions did not interfere with phosphate adsorption, while high concentration SO 4 2− and CO 3 2− affected the phosphate adsorption. In addition, adsorption mechanism analysis revealed that high-efficiency phosphate capture by MgAl-LDO was mainly due to the electrostatic adsorption, surface inner-sphere complexation, ligand exchange and precipitation combined process. Remarkably, the phosphate adsorbed MgAl-LDO (P-LDO) can be employed as synergistic flame retardant to improve the flame retardancy of paper. [ABSTRACT FROM AUTHOR]

In this paper, novel hydrogen-bonded metal-complex frameworks MPM-1-TIFSIX and HOF-21 were selected as adsorbents to adsorb iodine. MPM-1-TIFSIX and HOF-21 were prepared by layering method and mixed stirring method, respectively. The structures of the two HOFs were characterized in detail by XRD, BET, TGA and FT-IR. The adsorption behavior and adsorption capacity of MPM-1-TIFSIX and HOF-21 for iodine were investigated in detail. The experimental data showed that the equilibrium adsorption amounts of MPM-1-TIFSIX and HOF-21 were 205.51 mg/g and 172.86 mg/g, respectively. The adsorption process of MPM-1-TIFSIX was conformed to be pseudo-second-order kinetic, while the adsorption process of HOF-21 was conformed to be pseudo-first-order kinetic. The results indicated that HOFs could be used as iodine capture and storage materials. Two different structures of HOF materials were synthesized and used for the capture of iodine. Both materials have different properties, which are related to their structure. MPM-1-TIFSIX with a larger pore size is capable of adsorbing more iodine molecules. HOF-21 can only absorb a small amount of iodine due to the small pores, which can also be seen from the figure. Image 1 [ABSTRACT FROM AUTHOR]

ZIF-67@Yeast was synthesized with in-situ growth procedure by using hydrothermally carbonized yeast as the substrate material. The prepared ZIF-67@Yeast was characterized in detail by SEM, BET, XRD and TG analysis. In addition, the adsorption properties of Pb2+ by ZIF-67@Yeast were also investigated. The results show that the adsorption capacity of Pb2+ by ZIF-67@Yeast is larger than the sum of the adsorption capacity of Pb2+ by individual yeast and ZIF-67. Yeast could maintain a stable morphology after hydrothermal carbonization at 180 °C. Therefore, many MOFs synthesized by hydrothermal or microwave methods at 180 °C could also be compounded with Yeast as a base material. This provides more possibilities that heavy metal ions are adsorbed by the synthesis of more diverse MOFs composites. ZIF-67@Yeast was synthesized by in situ growth using a hydrothermally carbonized yeast as a substrate material, which can maintain a stable morphology and efficient removal of Pb2+ in water. Image 1 • ZIF-67@Yeast was synthesized by using a hydrothermally carbonized yeast as a substrate material. • The adsorption capacity of Pb2+ by ZIF-67@Yeast is larger than that of Pb2+ by individual yeast and ZIF-67. • Many MOFs could also be compounded with yeast as a base material. [ABSTRACT FROM AUTHOR]

Abstract Metal-organic frameworks (MOFs) benefitting from its controllable and diverse structure are a class of promising materials for diverse field. However, its directly employed for oxygen evolution reaction (OER) is still rare. Particularly, two-dimensional (2D) MOF nanosheets materials possess both advantages of 2D layered nanomaterials and MOFs, are considered as promising nanomaterials. Herein, we report a facile and scalable in situ hydrothermal synthesis of a 2D Co-based bimetallic MOFs (Co-Fe/Ni@HPA-MOF nanosheets), which can be stable in alkaline solution and directly adopted as highly efficient electrocatalysts. The Co-Ni@HPA-MOF can reach a current density of 10 mA cm−2 at low overpotential of 320 mV with a small Tafel slope of 58 mV dec−1, which is comparable to that of commercial RuO 2 (58 mV dec−1). The excellent electrocatalytic properties can be attributed to the 2D nanosheet and the coupling effect between Co and Ni, which provided large number of accessible active sites. The results highlight the great potential of utilizing MOF nanosheets for electrocatalysis, and will pave a way to develop more efficient 2D MOFs for diverse catalytic applications. Graphical abstract A facile and scalable in situ hydrothermal synthesis of a two dimensional Co-based bimetallic MOFs (Co-Fe/Ni@HPA-MOF nanosheets) was reported, which can be stable in alkaline solution and directly adopted as highly efficient electrocatalysts. fx1 Highlights • Two dimensional (2D) Co-based bimetallic metal-organic frameworks (MOFs) nanosheets were fabricated. • The Co-Ni@HPA-MOF nanosheet can reach a current density of 10 mA cm−2 at low overpotential of 320 mV. • The excellent electrocatalytic properties can be attributed to the coupling effect between Co and Ni. [ABSTRACT FROM AUTHOR]

Cellulose based Ag-functionalized ZnO nanocomposite (AZC) films were prepared using a green and easy scale-up strategy. Firstly, ZnO embedded cellulose (ZC) nanocomposite was synthesized from a cellulose-NaOH/zincate/urea solution through a biomimetic approach. Secondly, Ag nanoparticles (NPs) with a mean diameter of 53.2 nm were efficiently deposited onto the surface of embedded ZnO in cellulose matrix under UV irradiation (16 w), yielding the multi-hybrid AZC film. Owing to the porous structure of cellulose substrate and its rich hydroxyl group, the NPs in the ACZ films displayed good stability. Because of the formation of Schottky barriers in the Ag-ZnO regions, the catalytic activity of ACZ films increased by 20 times when compared to that of ZC sample. Furthermore, the AZC films could completely inhibit both S. aureus and E. coli growth. This facile and eco-friendly approach is expected to pave the way for constructing multifunctional cellulose material for various niche applications. [ABSTRACT FROM AUTHOR]

The low cost of adsorption treatment of heavy metal ions in water has been extensively studied. In this paper, we have demonstrated a facile method of combining two emerging materials cellulose aerogels (CA) and metal–organic frameworks (MOFs) into one highly functional aerogel to adsorption removal of heavy metal ions from water, by entrapping MOF particles into a flexible and porous CA. The resultant hybrid cellulose aerogels had a highly porous structure with zeolitic imidazolate framework-8 (ZIF-8) loadings can reach 30 wt%. The hybrid cellulose aerogels (named as ZIF-8@CA ) show good adsorption capacity for Cr(Ⅵ). The adsorption process of ZIF-8@CA is better described by pseudo-second-order kinetic model and Langmuir isotherm, with maximum monolayer adsorption capacity of 41.8 mg g −1 for Cr(Ⅵ), whose adsorption capacity has greatly improved when compared with a single CA or ZIF-8. Thus, such a flexible and durable hybrid cellulose aerogel is a very prospective material for metal ions cleanup and industrial wastewater purification. [ABSTRACT FROM AUTHOR]

In this paper, we reported the fabrication of Co-embedded nitrogen-doped carbon nanotube (Co-NCNT) by using Co-melamine coordination polymer (CP) as precursor. The sample was well characterized via SEM, TEM, XRD, XPS and BET methods. The Co-NCNT shows excellent and stable catalytic performance for OER. The overpotential of Co-NCNT at 10 mA cm -2 is 370 mV (vs RHE). The current density of Co-NCNT could reach 100 mA cm -2 at overpotential of 520 mV, which showed much better performance than RuO 2 , while the largest current density of RuO 2 could reach is only 44 mA cm -2 . The Tafel slope of Co-NCNT is 56 mV dec -1 , which is smaller than that of commercial RuO 2 (58 mV dec -1 ). The results indicate that metal-melamine based CPs or MOFs can be promising precursors for the preparation of efficient metal-embedded nitrogen-doped carbon materials for electrocatalysis. [ABSTRACT FROM AUTHOR]

Zr-based MOF structure UiO-66 exhibits unprecedented high thermal and chemical stability, making it to be one of the most used MOFs in various applications. Yet, the poor photoluminescent (PL) properties of UiO-66 limit its applications in luminescent sensing. Herein, a new benzimidazole-functionalized UiO-66 nanocrystal (UiO-66-BI) was successfully fabricated via microwave synthesis. UiO-66-BI displayed octahedral nanocrystal morphology with a diameter smaller than 200 nm and could disperse well in water and common organic solvents. UiO-66-BI demonstrated extended optical absorption in the visible-light region and efficiently improved PL emission compared with UiO-66 pristine. The sensing properties of UiO-66-BI nanocrystals towards different ions were studied, and the results demonstrated that UiO-66-BI showed excellent selective luminescent sensing of Fe 3+ ions in water. [ABSTRACT FROM AUTHOR]

Here we report a facile synthesis of nanorod-type graphitic carbon nitride/Fe 2 O 3 composite (Fe 2 O 3 - g -C 3 N 4 ) by using Fe-melamine supramolecular framework as precursor. The chemical and optical properties of the nanocomposites are well-characterized. The Fe 2 O 3 - g -C 3 N 4 nanocomposite demonstrated excellent photocatalytic activities under visible light due to the efficient utilization of sunlight and the construction of Z-scheme electron transfer pathway. The results indicated that it could be a promising approach for the preparation of efficient g -C 3 N 4 nanocomposites photocatalysts by using metal-melamine supramolecular framework as precursors. [ABSTRACT FROM AUTHOR]

Here we report a novel synthetic pathway for preparation of Cu-doped g -C 3 N 4 (Cu- g -C 3 N 4 ) with nanosheet morphology by using a two dimensional Cu–melamine supramolecular network as both sacrificial template and precursor. The specific surface area of Cu- g -C 3 N 4 is 40.86 m 2 g −1 , which is more than 7 times larger than that of pure g -C 3 N 4 . Cu- g -C 3 N 4 showed strong optical absorption in the visible-light region and expanded the absorption to the near-infrared region. The uniform nanosheet morphology, higher surface area and strong visible-light absorption have enabled Cu- g -C 3 N 4 exhibiting enhanced visible light photocatalytic activity for the photo-degradation of methylene blue (MB). The results indicate that metal–melamine supramolecular network can be promising precursors for the one step preparation of efficient metal-doped g -C 3 N 4 photocatalysts. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) can efficiently degrade stubborn organic pollutants via advanced oxidation process. However, it is essential to find ways to shape MOFs if its promise of practical application is to be realized. Herein, we develop a Zeolitic Imidazolate Framework-67 (ZIF-67)@cellulose aerogel (denoted as ZIF-67@CA) by a facile doping method. The strategy enhances actual macroscopic shape ability and external hierarchical porosity. Cellulose can provide mechanical flexibility to shape MOFs and promote recycle efficiency after water treatment. The novel doping method increases the loading and dispersibility of ZIF-67, which further increases the potential for the degradation of organic pollutants. ZIF-67@CA can take advantage of the accessible surface area and metal catalytic sites of ZIF-67 to activate peroxymonosulfate (PMS) efficiently and promote its degradation of p-nitrophenol (PNP) and tetracycline hydrochloride (TC). The degradation rate of organic pollutants is up to 80% within only 20 ​min. Furthermore, ZIF-67@CA exhibits excellent pH stability and recyclability so that it can be reused in harsh environments. Therefore, the low-cost and environmental-friendly production method can effectively recycle high-performance MOFs and expand its applications in a wider range of fields. Facile doping method is developed to fabricate the ZIF-67@CA. The strategy can effectively disperse MOFs uniformly. The ZIF-67@CA combines the degradation performance of MOFs and the shape ability of aerogels, which can effectively improve the degradation performance. The degradation mechanism shows that ZIF-67@CA can effectively purify organic pollutants in water. The strategy can be applied to various MOF catalysts in wastewater treatment and thereby expanding their application in a wider range of fields. Image 1 [ABSTRACT FROM AUTHOR]