Synthesis and Crystal Structures of Bis(diallydithiocarbamato)zinc(II) and Silver(I) Complexes: Precursors for Zinc Sulfide and Silver Sulfide Nanophotocatalysts.

We report the preparation and crystal structures of bis(diallydithiocarbamato)zinc(II) and silver(I) complexes. The compounds were used as single-source precursors to prepare zinc sulfide and silver sulfide nanophotocatalysts. The molecular structure of bis(diallydithiocarbamato)zinc(II) consists of a dimeric complex in which each zinc(II) ion asymmetrically coordinates with two diallydithiocarbamato anions in a bidentate chelating mode, and the centrosymmetrically related molecule is bridged through the S-atom that is chelated to the adjacent zinc(II) ion to form a distorted trigonal bipyramidal geometry around the zinc(II) ions. The molecular structure of bis(diallydithiocarbamato)silver(I) formed a cluster complex consisting of a trimetric Ag3S3 molecule in which the diallydithiocarbamato ligand is coordinated to all the Ag(I) ions. The complexes were thermolyzed in dodecylamine, hexadecylamine, and octadecylamine (ODA) to prepare zinc sulfide and silver sulfide nanoparticles. The powder X-ray diffraction patterns of the zinc sulfide nanoparticles correspond to the hexagonal wurtzite while silver sulfide is in the acanthite crystalline phase. The high-resolution transmission electron microscopy images show that quantum dot zinc sulfide nanoparticles are obtained with particle sizes ranging between 1.98 and 5.49 nm, whereas slightly bigger silver sulfide nanoparticles are obtained with particle sizes of 2.70-13.69 nm. The surface morphologies of the ZnS and AgS nanoparticles capped with the same capping agent are very similar. Optical studies revealed that the absorption band edges of the as-prepared zinc sulfide and silver sulfide nanoparticles were blue-shifted with respect to their bulk materials with some surface defects. The zinc sulfide and silver sulfide nanoparticles were used as nanophotocatalysts for the degradation of bromothymol blue (BTB) and bromophenol blue (BPB). ODA-capped zinc sulfide is the most efficient photocatalyst and degraded 87% of BTB and 91% of BPB.

Influence of Different Capping Agents on the Structural, Optical, and Photocatalytic Degradation Efficiency of Magnetite (Fe3O4) Nanoparticles.

Octylamine (OTA), 1-dodecanethiol (DDT), and tri-n-octylphosphine (TOP) capped magnetite nanoparticles were prepared by co-precipitation method. Powder X-ray diffraction patterns confirmed inverse spinel crystalline phases for the as-prepared iron oxide nanoparticles. Transmission electron microscopic micrographs showed iron oxide nanoparticles with mean particle sizes of 2.1 nm for Fe3O4-OTA, 5.0 nm for Fe3O4-DDT, and 4.4 nm for Fe3O4-TOP. The energy bandgap of the iron oxide nanoparticles ranges from 2.25 eV to 2.76 eV. The iron oxide nanoparticles were used as photocatalysts for the degradation of methylene blue with an efficiency of 55.5%, 58.3%, and 66.7% for Fe3O4-OTA, Fe3O4-DDT, and Fe3O4-TOP, respectively, while for methyl orange the degradation efficiencies were 63.8%, 47.7%, and 74.1%, respectively. The results showed that tri-n-octylphosphine capped iron oxide nanoparticles are the most efficient iron oxide nano-photocatalysts for the degradation of both dyes. Scavenger studies show that electrons (e-) and hydroxy radicals (•OH) contribute significantly to the photocatalytic degradation reaction of both methylene blue and methyl orange using Fe3O4-TOP nanoparticles. The influence of the dye solution's pH on the photocatalytic reaction reveals that a pH of 10 is the optimum for methylene blue degradation, whereas a pH of 2 is best for methyl orange photocatalytic degradation using the as-prepared iron oxide nano-photocatalyst. Recyclability studies revealed that the iron oxide photocatalysts can be recycled three times without losing their photocatalytic activity.

Multidrug-Resistant Biofilm, Quorum Sensing, Quorum Quenching, and Antibacterial Activities of Indole Derivatives as Potential Eradication Approaches.

Challenges encountered in relapse of illness caused by resistance of microorganisms to antimicrobial agents (drugs) are due to factors of severe stress initiated by random use of antibiotics and insufficient beneficial approaches. These challenges have resulted to multiple drug resistance (MDR) and, subsequently, biofilm formation. A type of intercellular communication signal called quorum sensing (QS) has been studied to cause the spread of resistance, thereby enabling a formation of stable community for microorganisms. The QS could be inhibited using QS inhibitors (QSIs) called quorum-quenching (QQ). The QQ is an antibiofilm agent. Indole derivatives from plant sources can serve as quorum-quenching eradication approach for biofilm, as well as a promising nontoxic antibiofilm agent. In other words, phytochemicals in plants help to control and prevent biofilm formation. It could be recommended that combination strategies of these indoles' derivatives with antibiotics would yield enhanced results.

Synthesis of Metal-Organic Frameworks Quantum Dots Composites as Sensors for Endocrine-Disrupting Chemicals.

Hazardous chemical compounds such as endocrine-disrupting chemicals (EDCs) are widespread and part of the materials we use daily. Among these compounds, bisphenol A (BPA) is the most common endocrine-disrupting chemical and is prevalent due to the chemical raw materials used to manufacture thermoplastic polymers, rigid foams, and industrial coatings. General exposure to endocrine-disrupting chemicals constitutes a serious health hazard, especially to reproductive systems, and can lead to transgenerational diseases in adults due to exposure to these chemicals over several years. Thus, it is necessary to develop sensors for early detection of endocrine-disrupting chemicals. In recent years, the use of metal-organic frameworks (MOFs) as sensors for EDCs has been explored due to their distinctive characteristics, such as wide surface area, outstanding chemical fastness, structural tuneability, gas storage, molecular separation, proton conductivity, and catalyst activity, among others which can be modified to sense hazardous environmental pollutants such as EDCs. In order to improve the versatility of MOFs as sensors, semiconductor quantum dots have been introduced into the MOF pores to form metal-organic frameworks/quantum dots composites. These composites possess a large optical absorption coefficient, low toxicity, direct bandgap, formidable sensing capacity, high resistance to change under light and tunable visual qualities by varying the size and compositions, which make them useful for applications as sensors for probing of dangerous and risky environmental contaminants such as EDCs and more. In this review, we explore various synthetic strategies of (MOFs), quantum dots (QDs), and metal-organic framework quantum dots composites (MOFs@QDs) as efficient compounds for the sensing of ecological pollutants, contaminants, and toxicants such as EDCs. We also summarize various compounds or materials used in the detection of BPA as well as the sensing ability and capability of MOFs, QDs, and MOFs@QDs composites that can be used as sensors for EDCs and BPA.

Assessment of physiological and electrochemical effects of a repurposed zinc dithiocarbamate complex on Acinetobacter baumannii biofilms.

Acinetobacter baumannii is an infectious agent of global proportion and concern, partly due to its proficiency in development of antibiotic resistance phenotypes and biofilm formation. Dithiocarbamates (DTC) have been identified as possible alternatives to the current antimicrobials. We report here the evaluation of several DTC-metal complexes against A. baumannii planktonic cells and biofilms. Among the DTC-metal complexes and DTCs tested, ZnL1 (N-methyl-1-phenyldithiocarbamato-S,S' Zn(II)), originally designed as an antitumor agent, is effective against biofilm forming A. baumannii. A MIC value of 12.5 µM, comparable to that of Gentamicin (5 µM) was measured for planktonic cells in tryptic soy broth. Spectroscopy, microscopy and biochemical analyses reveal cell membrane degradation and leakage after treatment with ZnL1. Bioelectrochemical analyses show that ZnL1 reduces biofilm formation and decreases extracellular respiration of pre-formed biofilms, as corroborated by microscopic analyses. Due to the affinity of Zn to cells and the metal chelating nature of L1 ligand, we hypothesize ZnL1 could alter metalloprotein functions in the membranes of A. baumannii cells, leading to altered redox balance. Results indicate that the DTC-Zn metal complex is an effective antimicrobial agent against early A. baumannii biofilms under laboratory conditions.

Photocatalytic Degradation of Single and Binary Mixture of Brilliant Green and Rhodamine B Dyes by Zinc Sulfide Quantum Dots.

We present the preparation of octadecylamine-capped ZnS quantum dots from bis(morpholinyldithiocarbamato)Zn(II) complex. The complex was thermolyzed at 130 °C in octadecylamine at different times, to study the effect of reaction time on the morphological and photocatalytic properties of the ZnS quantum dots. Powder X-ray diffraction patterns confirmed a hexagonal wurtzite crystalline phase of ZnS, while HRTEM images showed particle sizes of about 1-3 nm, and energy band gaps of 3.68 eV (ZnS-1), 3.87 eV (ZnS-2), and 4.16 eV (ZnS-3) were obtained from the Tauc plot for the ZnS nanoparticles. The as-prepared ZnS were used as photocatalysts for the degradation of brilliant green, rhodamine B, and binary dye consisting of a mixture of brilliant green-rhodamine B. The highest photocatalytic degradation efficiency of 94% was obtained from ZnS-3 with low photoluminescence intensity. The effect of catalytic dosage and pH of the dyes solution on the photocatalytic process shows that pH 8 is optimal for the degradation of brilliant green, while pH 6.5 is the best for photocatalytic degradation of rhodamine B. The degradation of the binary dyes followed the same trends. The effect of catalytic dosage shows that 1 mg mL-1 of the ZnS nano-photocatalyst is the optimum dosage for the degradation of organic dyes. Reusability studies show that the ZnS quantum dots can be reused five times without a significant reduction in degradation efficiency.

Bis(4-methylpiperidine-1-carbodithioato)-lead(II) and Bis(4-benzylpiperidine-1-carbodithioato)-lead(II) as Precursors for Lead Sulphide Nano Photocatalysts for the Degradation of Rhodamine B.

Bis(4-methylpiperidine-1-carbodithioato)-lead(II) and bis(4-benzylpiperidine-1-carbodithioato)-lead(II) were prepared and their molecular structures elucidated using single crystal X-ray crystallography and spectroscopic techniques. The compounds were used as precursors for the preparation of lead sulphide nano photocatalysts for the degradation of rhodamine B. The single crystal structures of the lead(II) dithiocarbamate complexes show mononuclear lead(II) compounds in which each lead(II) ion coordinates two dithiocarbamato anions in a distorted tetrahedral geometry. The compounds were thermolyzed at 180 ℃ in hexadecylamine (HDA), octadecylamine (ODA), and trioctylphosphine oxide (TOPO) to prepare HDA, ODA, and TOPO capped lead sulphide (PbS) nanoparticles. Powder X-ray diffraction (pXRD) patterns of the lead sulphide nanoparticles were indexed to the rock cubic salt crystalline phase of lead sulphide. The lead sulphide nanoparticles were used as photocatalysts for the degradation of rhodamine B with ODA-PbS1 achieving photodegradation efficiency of 45.28% after 360 min. The photostability and reusability studies of the as-prepared PbS nanoparticles were studied in four consecutive cycles, showing that the percentage degradation efficiency decreased slightly by about 0.51-1.93%. The results show that the as-prepared PbS nanoparticles are relatively photostable with a slight loss of photodegradation activities as the reusability cycles progress.

Metal Sulfide Semiconductor Nanomaterials and Polymer Microgels for Biomedical Applications.

The development of nanomaterials with therapeutic and/or diagnostic properties has been an active area of research in biomedical sciences over the past decade. Nanomaterials have been identified as significant medical tools with potential therapeutic and diagnostic capabilities that are practically impossible to accomplish using larger molecules or bulk materials. Fabrication of nanomaterials is the most effective platform to engineer therapeutic agents and delivery systems for the treatment of cancer. This is mostly due to the high selectivity of nanomaterials for cancerous cells, which is attributable to the porous morphology of tumour cells which allows nanomaterials to accumulate more in tumour cells more than in normal cells. Nanomaterials can be used as potential drug delivery systems since they exist in similar scale as proteins. The unique properties of nanomaterials have drawn a lot of interest from researchers in search of new chemotherapeutic treatment for cancer. Metal sulfide nanomaterials have emerged as the most used frameworks in the past decade, but they tend to aggregate because of their high surface energy which triggers the thermodynamically favoured interaction. Stabilizing agents such as polymer and microgels have been utilized to inhibit the particles from any aggregations. In this review, we explore the development of metal sulfide polymer/microgel nanocomposites as therapeutic agents against cancerous cells.

Enhanced Photocatalytic Degradation of Ternary Dyes by Copper Sulfide Nanoparticles.

We report the effect of thermolysis time on the morphological and optical properties of CuS nanoparticles prepared from Cu(II) dithiocarbamate single-source precursor. The as-prepared copper sulfide nanoparticles were used as photocatalysts for the degradation of crystal violet (CV), methylene blue (MB), rhodamine B (RhB), and a ternary mixture of the three dyes (CV/MB/RhB). Powder XRD patterns confirmed the hexagonal covellite phase for the CuS nanoparticles. At the same time, HRTEM images revealed mixed shapes with a particle size of 31.47 nm for CuS1 prepared at 30 min while CuS2 prepared at 1 h consists of mixtures of hexagonal and nanorods shaped particles with an average size of 21.59 nm. Mixed hexagonal and spherically shaped particles with a size of 17.77 nm were obtained for CuS3 prepared at 2 h. The optical bandgaps of the nanoparticles are 3.00 eV for CuS1, 3.26 eV for CuS2 and 3.13 eV for CuS3. The photocatalytic degradation efficiency showed that CuS3 with the smallest particle size is the most efficient photocatalyst and degraded 85% of CV, 100% of MB, and 81% of RhB. The as-prepared CuS showed good stability and recyclability and also degraded ternary dyes mixture (CV/MB/RhB) effectively. The byproducts of the dye degradation were evaluated using ESI-mass spectrometry.

Synthesis and Structural Studies of Manganese Ferrite and Zinc Ferrite Nanocomposites and Their Use as Photoadsorbents for Indigo Carmine and Methylene Blue Dyes.

Solar-moderated adsorptions of indigo carmine and methylene blue dyes were investigated using manganese and zinc ferrite capped with biochar prepared from the root of Chromolaena odorata. TEM micrograph of the as-prepared manganese ferrite nanocomposites (MnFe2O4@BC) revealed octagonally shaped particles with an average size of 42.64 nm while the zinc ferrite nanocomposite (ZnFe2O4@BC) micrograph revealed mixtures of rod- and cone-shaped particles with an average size of 43.82 nm. Biochar capping of MnFe2O4@BC reduced the band gap from 3.63 to 2.08 eV. The nanocomposite surface areas were 197.64 and 92.14 m2/g for MnFe2O4@BC and ZnFe2O4@BC, respectively. Photoadsorption of the as-prepared nanocomposites showed that 10 mg of ZnFe2O4@BC effectively removed 69.07 and 98.60% of 70 mg/L indigo carmine and methylene blue dyes while MnFe2O4@BC removed 77.65 and 94.83% of indigo carmine and methylene blue dyes after 2 h of equilibration under visible light irradiation, respectively. The nonlinear form of the Langmuir isotherm had a better approximation to the experimental solid-phase concentration (q e) for the adsorption of indigo carmine dye using both nanocomposites. In contrast, the linear form gave a better goodness-of-fit for the adsorptions of methylene blue dye. The manganese ferrite (MnFe2O4@BC) and zinc ferrite (ZnFe2O4@BC) nanocomposites showed no inhibition of Escherichia coli and Staphylococcus aureus, which indicates that they could be used for both biological and environmental applications.

Morphological Studies, Photocatalytic Activity, and Electrochemistry of Platinum Disulfide Nanoparticles from Bis(morpholinyl-4-carbodithioato)-platinum(II).

Bis(morpholinyl-4-carbodithioato)-platinum(II) was synthesized and characterized using spectroscopic techniques and single-crystal X-ray crystallography. The Pt(II) complex crystallized in a monoclinic space group P21/n with a Pt(II) ion located on an inversion center coordinated two morpholinyl dithiocarbamate ligands that are coplanar to form a slightly distorted square planar geometry around the Pt(II) ion. The complex was thermolyzed at 120, 180, and 240 °C to prepare PtS2 nanoparticles. Powder X-ray diffraction patterns confirmed the hexagonal crystalline phase for the as-prepared PtS2 nanoparticles irrespective of thermolysis temperature. Bead-like shaped PtS2-120 nanoparticles with a particle size in the range of 12.46-64.97 nm were formed at 120 °C, while PtS2-180 prepared at 180 °C is quasi-spherical in shape with particles in the range of 24.30-46.87 nm. The PtS2-240 obtained at 240 °C is spherical with particles in the range of 11.45-46.85 nm. The broad emission maxima of the as-prepared PtS2 nanoparticles are ascribed to the particles' broad size distributions. The photocatalytic degradation of methylene blue by the PtS2 nanoparticles shows a maximum efficiency of 87% for PtS2-240 after 360 min. The effects of photocatalytic dosage, irradiation time, pH medium, and scavengers were also evaluated. Cyclic voltammetry of the PtS2 nanoparticles showed a reversible redox reaction, while the electrochemistry of the as-prepared PtS2 indicates that the electron transfer process is diffusion-controlled.

Multifunctional Magnetic Oxide Nanoparticle (MNP) Core-Shell: Review of Synthesis, Structural Studies and Application for Wastewater Treatment.

The demand for water is predicted to increase significantly over the coming decades; thus, there is a need to develop an inclusive wastewater decontaminator for the effective management and conservation of water. Magnetic oxide nanocomposites have great potentials as global and novel remediators for wastewater treatment, with robust environmental and economic gains. Environment-responsive nanocomposites would offer wide flexibility to harvest and utilize massive untapped natural energy sources to drive a green economy in tandem with the United Nations Sustainable Development Goals. Recent attempts to engineer smart magnetic oxide nanocomposites for wastewater treatment has been reported by several researchers. However, the magnetic properties of superparamagnetic nanocomposite materials and their adsorption properties nexus as fundamental to the design of recyclable nanomaterials are desirable for industrial application. The potentials of facile magnetic recovery, ease of functionalization, reusability, solar responsiveness, biocompatibility and ergonomic design promote the application of magnetic oxide nanocomposites in wastewater treatment. The review makes a holistic attempt to explore magnetic oxide nanocomposites for wastewater treatment; futuristic smart magnetic oxides as an elixir to global water scarcity is expounded. Desirable adsorption parameters and properties of magnetic oxides nanocomposites are explored while considering their fate in biological and environmental media.

Data for experimental and calculated values of the adsorption of Pb(II) and Cr(VI) on APTES functionalized magnetite biochar using Langmuir, Freundlich and Temkin equations.

Adsorption isotherms are indispensable tools for the description of sorption processes of pollutants on adsorbents. The closeness of the equilibrium concentration (qe) to the calculated solid phase concentration (qecal) of the adsorbate, together with the co-efficient of determination (R2) and associated errors are important in determining the best goodness-of-fit model. In this work we have investigated the adsorption of Pb(II) and Cr(VI) on a nanocomposite that was prepared using magnetite nanoparticles capped with locally prepared biochar and functionalized using 3-(aminopropyl) triethoxysilane (APTES) at 3 different temperatures. Detailed discussion of data can be found in DOI:10.1016/j.micromeso.2020.110573. The sorption processes were equally analyzed utilizing both the linear and non-linear forms of Langmuir, Freundlich and Temkin equations.

Synthesis, Crystal Structures and Anticancer Studies of Morpholinyldithiocarbamato Cu(II) and Zn(II) Complexes.

Cu(II) and Zn(II) morpholinyldithiocarbamato complexes, formulated as [Cu(MphDTC)2] and [Zn(µ-MphDTC)2(MphDTC)2], where MphDTC is morpholinyldithiocarbamate were synthesized and characterized by elemental analysis, spectroscopic techniques and single-crystal X-ray crystallography. The molecular structure of the Cu(II) complex revealed a mononuclear compound in which the Cu(II) ion was bonded to two morpholinyl dithiocarbamate ligands to form a four-coordinate distorted square planar geometry. The molecular structure of the Zn(II) complex was revealed to be dinuclear, and each metal ion was bonded to two morpholinyl dithiocarbamate bidentate anions, one acting as chelating ligand, the other as a bridge between the two Zn(II) ions. The anticancer activity of the morpholinyldithiocarbamate ligand, Cu(II) and Zn(II) complexes were evaluated against renal (TK10), melanoma (UACC62) and breast (MCF7) cancer cells by a Sulforhodamine B (SRB) assay. Morpholinyldithiocarbamate was more active than the standard drug parthenolide against renal and breast cancer cell lines, and [Zn(µ-MphDTC)2(MphDTC)2] was the most active complex against breast cancer. The copper(II) complex had a comparable activity with the standard against renal and breast cancer cell lines but showed an enhanced potency against melanoma when compared to parthenolide.

Impact of Molybdenum Compounds as Anticancer Agents.

The aim of this mini review was to report the molybdenum compound intervention to control cancer disease. The intervention explains its roles and progress from inorganic molybdenum compounds via organomolybdenum complexes to its nanoparticles to control oesophageal cancer and breast cancer as case studies. Main contributions of molybdenum compounds as anticancer agents could be observed in their nanofibrous support with suitable physicochemical properties, combination therapy, and biosensors (biomarkers). Recent areas in anticancer drug design, which entail the uses of selected targets, were also surveyed and proposed.

Dithiocarbamates: Challenges, Control, and Approaches to Excellent Yield, Characterization, and Their Biological Applications.

Progresses made in previous researches on syntheses of dithiocarbamates led to increase in further researches. This paper reviews concisely the challenges experienced during the synthesis of dithiocarbamate and mechanisms to overcome them in order to obtain accurate results. Aspects of its precursor's uses to synthesize adducts, nanoparticles, and nanocomposites are reported. Some common characterization techniques used for the synthesized products were assessed. Biological applications are also reported.

Retraction: Ajibade, P.A., et al. Synthesis, Optical and Structural Properties of Copper Sulfide Nanocrystals from Single Molecule Precursors. Nanomaterials 2017, 7, 32.

The Nanomaterials Editorial Office has been made aware that the published paper [...].

The Anticancer Activities of Some Nitrogen Donor Ligands Containing bis-Pyrazole, Bipyridine, and Phenanthroline Moiety Using Docking Methods.

The anticancer study of nitrogen-chelating ligands can be of tremendous help in choosing ligands for the anticancer metal complexes design especially with ruthenium(II). The inhibitory anticancer activities of some nitrogen-chelating ligands containing bis-pyrazole, bipyridine, and phenanthroline were studied using experimental screening against cancer cell and theoretical docking methods. In vitro anticancer activities showed compound 11 as the most promising inhibitor, and the computational docking further indicates its strong inhibitory activities towards some cancer-related receptors. Among the twenty-one modelled ligands, pyrazole-based compounds 7, 11, and 15 are the most promising inhibitors against the selected receptors followed by 18 and 21 which are derivatives of pyridine and phenanthroline, respectively. The presence of the carboxylic unit in the top five ligands that displayed stronger inhibitory activities against the selected receptors is an indication that the formation of noncovalent interactions such as hydrogen bonding and a strong electron-withdrawing group in these compounds are very important for their receptor interactions. The thermodynamic properties, the polarizabilities, and the LUMO energy of the compounds are in the same patterns as the observed inhibitory activities.

Synthesis, Optical, and Structural Studies of Iron Sulphide Nanoparticles and Iron Sulphide Hydroxyethyl Cellulose Nanocomposites from Bis-(Dithiocarbamato)Iron(II) Single-Source Precursors.

In this study, Fe(II) complexes of phenyldithiocarbamate, dimethyldithiocarbamate and imidazolyldithiocarbamate were used as single-source precursors to prepare iron sulphide nanoparticles by thermolysis in oleic acid/octadecylamine (ODA) at 180 °C. The nanoparticles were dispersed into hydroxyethyl cellulose (HEC) to prepare iron sulphide/HEC nanocomposites. Ultraviolet-Visible (UV-Vis), Photoluminescence (PL), Fourier Transform Infrared (FTIR), powder X-ray diffraction (pXRD), high-resolution transmission electron microscopy (HRTEM), Field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDS) were used to characterize the iron sulphide nanoparticles and corresponding HEC nanocomposites. The absorption spectra studies revealed that the nanoparticles were blue shifted due to quantum confinement and the optical band gaps of the nanoparticles are 4.85 eV for FeS1, 4.36 eV for FeS2, and 4.77 eV for FeS3. The emission maxima are red-shifted and broader for the nanoparticles prepared from phenyldithiocarbamate. Rod-like and spherically shaped iron sulphide particles were observed from the HRTEM images. The crystallite sizes from the HRTEM images are 23.90-38.89 nm for FeS1, 4.50-10.50 nm for FeS2, and 6.05-6.19 nm for FeS3 iron sulphide nanoparticles, respectively. pXRD diffraction patterns confirmed that FeS1 is in the pyrrhotite-4M crystalline phase, FeS2 is in the pyrrhotite phase, and FeS3 is in the troilite phase of iron sulphide. The phases of the iron sulphide nanoparticles indicate that the nature of the precursor complex affects the obtained crystalline phase. FTIR spectra studies confirmed the incorporation of the nanoparticles in the HEC matrix by the slight shift of the O-H and C-O bonds and the intense peaks on the nanoparticles. FESEM images of the iron sulphide nanoparticles showed flake-like or leaf-like morphologies with some hollow spheres. The EDS confirmed the formation of iron sulphide nanoparticles by showing the peaks of Fe and S.

Synthesis of zinc-carboxylate metal-organic frameworks for the removal of emerging drug contaminant (amodiaquine) from aqueous solution.

We herein report the removal of amodiaquine, an emerging drug contaminant from aqueous solution using [Zn2(fum)2(bpy)] and [Zn4O(bdc)3] (fum=fumaric acid; bpy=4,4-bipyridine; bdc=benzene-1,4-dicarboxylate) metal-organic frameworks (MOFs) as adsorbents. The adsorbents were characterized by elemental analysis, Fourier transform infrared (FT-IR) spectroscopy, and powder X-ray diffraction (PXRD). Adsorption process for both adsorbents were found to follow the pseudo-first-order kinetics, and the adsorption equilibrium data fitted best into the Freundlich isotherm with the R2 values of 0.973 and 0.993 obtained for [Zn2(fum)2(bpy)] and [Zn4O(bdc)3] respectively. The maximum adsorption capacities foramodiaquine in this study were found to be 0.478 and 47.62mg/g on the [Zn2(fum)2(bpy)] and [Zn4O(bdc)3] MOFs respectively, and were obtained at pH of 4.3 for both adsorbents. FT-IR spectroscopy analysis of the MOFs after the adsorption process showed the presence of the drug. The results of the study showed that the prepared MOFs could be used for the removal of amodiaquine from wastewater.