Mercury Removal from Aqueous Solutions Using Modified Pyrite: A Column Experiment

Modified pyrite (MPy), which was obtained from calcination in an N2 atmosphere, was used as a sorbent for removing Hg(II) from aqueous solutions. Fixed-bed column experiments were conducted to determine the Hg(II) removal ability of MPy from aqueous solutions. MPy was found to be much better than natural pyrite for mercury removal. The concentration of Hg(II) in effluents was much lower than that of the emission standard used for Hg wastewater in China (0.05 mg/L), and the removal efficiency of Hg(II) was greater than 99% before breakthrough. When the capacity was 3274 times the column bed volume (1 bed volume = 25.12 cm3), the column breakthrough and the sorption amount of Hg(II) were 54.44 mg/g. The Hg(II) content in the used MPy sorbent was up to 24.79%. The mechanism was analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), field emission transmission electron microscopy (FE-TEM), and X-ray Photoelectron Spectroscopy (XPS). The main mechanism of Hg(II) removal by MPy was the chemical reactions between mercury ions and mineral fillers, and HgS precipitated on the surface of MPy to remove Hg(II). The reaction was also accompanied by surface complexation and adsorption. The results of this work show that MPy can be used as a sorbent for continuous Hg(II) removal.

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Thermoelectric Generator Using Polyaniline-Coated Sb2Se3/β-Cu2Se Flexible Thermoelectric Films

Polymers ◽

10.3390/polym13091518 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1518

Author(s):

Minsu Kim ◽

Dabin Park ◽

Jooheon Kim

Keyword(s):

Electron Microscopy ◽

Electrical Conductivity ◽

Field Emission ◽

Photoelectron Spectroscopy ◽

Thermoelectric Generator ◽

Hydrothermal Reaction ◽

Water Evaporation ◽

Pani Film ◽

Portable Devices ◽

X Ray

Herein, Sb2Se3 and β-Cu2Se nanowires are synthesized via hydrothermal reaction and water evaporation-induced self-assembly methods, respectively. The successful syntheses and morphologies of the Sb2Se3 and β-Cu2Se nanowires are confirmed via X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), and field emission transmission electron microscopy (FE-TEM). Sb2Se3 materials have low electrical conductivity which limits application to the thermoelectric generator. To improve the electrical conductivity of the Sb2Se3 and β-Cu2Se nanowires, polyaniline (PANI) is coated onto the surface and confirmed via Fourier-transform infrared spectroscopy (FT-IR), FE-TEM, and XPS analysis. After coating PANI, the electrical conductivities of Sb2Se3/β-Cu2Se/PANI composites were increased. The thermoelectric performance of the flexible Sb2Se3/β-Cu2Se/PANI films is then measured, and the 70%-Sb2Se3/30%-β-Cu2Se/PANI film is shown to provide the highest power factor of 181.61 μW/m·K2 at 473 K. In addition, a thermoelectric generator consisting of five legs of the 70%-Sb2Se3/30%-β-Cu2Se/PANI film is constructed and shown to provide an open-circuit voltage of 7.9 mV and an output power of 80.1 nW at ΔT = 30 K. This study demonstrates that the combination of inorganic thermoelectric materials and flexible polymers can generate power in wearable or portable devices.

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Uranium(VI) interaction with pyrite (FeS2): Chemical and spectroscopic studies

Radiochimica Acta ◽

10.1524/ract.2006.94.9-11.651 ◽

2006 ◽

Vol 94 (9-11) ◽

Cited By ~ 21

Author(s):

Noelle Eglizaud ◽

F. Miserque ◽

E. Simoni ◽

M. Schlegel ◽

M. Descostes

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Spectroscopic Studies ◽

Solution Chemistry ◽

X Ray Diffraction ◽

X Ray ◽

Natural Pyrite ◽

Scanning Electron

The mechanism of uranium(VI) interaction with pyrite was studied by solution chemistry and X-ray Photoelectron Spectroscopy (XPS). Natural pyrite was characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). After equilibration in 10

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Ethanol Sensing Properties and First Principles Study of Au Supported on Mesoporous ZnO Derived from Metal Organic Framework ZIF-8

Sensors ◽

10.3390/s21134352 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4352

Author(s):

Yanli Kang ◽

Lu Zhang ◽

Wenhao Wang ◽

Feng Yu

Keyword(s):

Electron Microscopy ◽

Field Emission ◽

Adsorption Energy ◽

Photoelectron Spectroscopy ◽

Density Functional ◽

Metal Organic Framework ◽

X Ray ◽

Metal Organic ◽

Mesoporous Zno ◽

Organic Framework

It is of great significance to develop ethanol sensors with high sensitivity and low detection temperature. Hence, we prepared Au-supported material on mesoporous ZnO composites derived from a metal-organic framework ZIF-8 for the detection of ethanol gas. The obtained Au/ZnO materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (SEM), field emission transmission electron microscopy (TEM) and nitrogen adsorption and desorption isotherms. The results showed that the Au/ZnO-1.0 sample maintains a three-dimensional (3D) dodecahedron structure with a larger specific surface area (22.79 m2 g−1) and has more oxygen vacancies. Because of the unique ZIF structure, abundant surface defects and the formation of Au-ZnO Schottky junctions, an Au/ZnO-1.0 sensor has a response factor of 37.74 for 100 ppm ethanol at 250 °C, which is about 6 times that of pure ZnO material. In addition, the Au/ZnO-1.0 sensor has good selectivity for ethanol. According to density functional theory (DFT) calculations, the adsorption energy of Au/ZnO for ethanol (−1.813 eV) is significantly greater than that of pure ZnO (−0.217 eV). Furthermore, the adsorption energy for ethanol is greater than that of other gases.

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SYNTHESIS AND FIELD EMISSION PROPERTIES OF SnS2 AND In-DOPED SnS2 WITH HIERARCHICAL STRUCTURE

NANO ◽

10.1142/s1793292011002810 ◽

2011 ◽

Vol 06 (05) ◽

pp. 489-496 ◽

Cited By ~ 2

Author(s):

H. X. ZHONG ◽

C. X. WANG

Keyword(s):

Electron Microscopy ◽

Field Emission ◽

Photoelectron Spectroscopy ◽

Sulfur Source ◽

X Ray Diffraction ◽

Hydrothermal Route ◽

X Ray ◽

Emission Properties ◽

Field Emission Properties ◽

Transmission Electron

A simple hydrothermal route was employed to prepare flower-like SnS2 and In -doped SnS2 by using biomolecular L-cysteine as sulfur source. The synthetic samples were characterized by X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy in detail. Furthermore, the field emission from both the materials was investigated, it was found that both of them have excellent field emission properties, and the doped In has enhanced the field emission properties.

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Study on the Adsorption Properties of Iron Tailings for GO

Coatings ◽

10.3390/coatings11070768 ◽

2021 ◽

Vol 11 (7) ◽

pp. 768

Author(s):

Jiawei Zhou ◽

Liming Yao ◽

Yunfeng Wang ◽

Weiqi Zhao ◽

Jiahui Gu

Keyword(s):

Electron Microscopy ◽

Aqueous Solutions ◽

Photoelectron Spectroscopy ◽

Adsorption Process ◽

Physical Adsorption ◽

Exothermic Reaction ◽

Single Layer ◽

X Ray ◽

Force Microscopy ◽

Transmission Electron

Iron tailings can be used as adsorbents to effectively remove graphene oxide (GO) in aqueous solutions. Experimental data show that pH, iron tailing quality, GO concentration and temperature have significant effects on the removal of GO, the adsorption of the tail involves a single layer adsorbed Langmuir model with exothermic reaction, and it compliance with the proposed dynamics model meets the requirements, the adsorption process is a spontaneous physical adsorption process. Combining scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) to analyze the iron tail according to the mechanisms of ore adsorption of GO, it was concluded that iron tailings might be a very promising material to effectively remove GO in aqueous solutions. The results of this research provide key information for the transportation and potential fate of GO in the natural environment.

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Direct Growth of CuO Particles on Carbon Papers for High-Performance Rechargeable Li–O2 Batteries

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19227 ◽

2021 ◽

Vol 21 (7) ◽

pp. 3903-3908

Author(s):

Inhan Kang ◽

Jungwon Kang

Keyword(s):

Electron Microscopy ◽

Energy Efficiency ◽

Field Emission ◽

Photoelectron Spectroscopy ◽

High Performance ◽

Storage System ◽

Energy Storage System ◽

High Energy ◽

Heating Process ◽

X Ray

Lithium–oxygen (Li–O2) batteries are considered as a promising high-energy storage system. However, they suffer from overpotential and low energy efficiency. This study showed that CuO growth on carbon using facile synthesis (simple dipping and heating process) reduces overpotential, thus increasing the energy efficiency. We confirmed the structure of CuO on carbon using X-ray diffraction pattern, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, and field-emission transmission electron microscopy. The cathode of CuO on carbon shows an average overpotential reduction of ˜6% charge/discharge during 10 cycles in nonaqueous Li–O2 batteries. The possible reason for the reduced charge overpotential of the cathode of CuO on carbon is attributed to the formed Li2O2 of smaller particle size during discharging compared to pristine carbon.

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Preparation and characterization of magnetic graphene oxide nanocomposite (GO-Fe3O4) for removal of strontium and cesium from aqueous solutions

Characterization and Application of Nanomaterials ◽

10.24294/can.v4i1.1291 ◽

2021 ◽

Vol 4 (1) ◽

pp. 26

Author(s):

Sule Aytas ◽

Sabriye Yusan ◽

Senol Sert ◽

Cem Gok

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Aqueous Solutions ◽

Photoelectron Spectroscopy ◽

Precipitation Method ◽

Magnetic Graphene Oxide ◽

X Ray ◽

Magnetic Graphene ◽

Transmission Electron ◽

Co Precipitation

Magnetic graphene oxide nanocomposites (M-GO) were successfully synthesized by partial reduction co-precipitation method and used for removal of Sr(II) and Cs(I) ions from aqueous solutions. The structures and properties of the M-GO was investigated by X-ray diffraction, Fourier transformed infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy, vibrating sample magnetometer (VSM) and N2-BET measurements. It is found that M-GO has 2.103 mg/g and 142.070 mg/g adsorption capacities for Sr(II) and Cs(I) ions, respectively. The adsorption isotherm matches well with the Freundlich for Sr(II) and Dubinin–Radushkevich model for Cs(I) and kinetic analysis suggests that the adsorption process is pseudo-second-ordered.

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Preparation and characterization of magnetic graphene oxide nanocomposite (GO-Fe3O4) for removal of strontium and cesium from aqueous solutions

Composite Materials Research ◽

10.18282/cmr.v7i1.89 ◽

2018 ◽

Vol 7 (1) ◽

Author(s):

Sabriye Yusan

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Aqueous Solutions ◽

Photoelectron Spectroscopy ◽

Precipitation Method ◽

Magnetic Graphene Oxide ◽

X Ray ◽

Magnetic Graphene ◽

Transmission Electron ◽

Co Precipitation

<p>Magnetic graphene oxide nanocomposites (M-GO) were successfully synthesized by partial reduction co-precipitation method and used for removal of Sr(II) and Cs(I) ions from aqueous solutions. The structures and properties of the M-GO was investigated by X-ray diffraction, Fourier transformed infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy, vibrating sample magnetometer (VSM) and N<sub>2</sub>-BET measurements. It is found that M-GO has 2.103 mg/g and 142.070 mg/g adsorption capacities for Sr(II) and Cs(I) ions, respectively. The adsorption isotherm matches well with the Freundlich for Sr(II) and Dubinin–Radushkevich model for Cs(I) and kinetic analysis suggests that the adsorption process is pseudo-second-ordered.</p>

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Antibacterial silver-diatomite nanocomposite ceramic with low silver release

Water Science & Technology Water Supply ◽

10.2166/ws.2019.195 ◽

2019 ◽

Vol 20 (2) ◽

pp. 633-643

Author(s):

Xiaopeng Qi ◽

Junwei Chen ◽

Qian Li ◽

Hui Yang ◽

Honghui Jiang ◽

...

Keyword(s):

Electron Microscopy ◽

Water Treatment ◽

Photoelectron Spectroscopy ◽

Bactericidal Effect ◽

Ceramic Filter ◽

Ceramic Filters ◽

X Ray ◽

E Coli ◽

Point Of Use ◽

Silver Release

Abstract There is an urgent need for an effective and long-lasting ceramic filter for point-of-use water treatment. In this study, silver-diatomite nanocomposite ceramic filters were developed by an easy and effective method. The ceramic filters have a three-dimensional interconnected pore structure and porosity of 50.85%. Characterizations of the silver-diatomite nanocomposite ceramic filters were performed using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Silver nanoparticles were confirmed to be formed in situ in the ceramic filter. The highest silver concentration in water was 0.24 μg/L and 2.1 μg/L in short- and long-term experiments, indicating very low silver-release properties of silver-diatomite nanocomposite ceramic filter. The nanocomposite ceramics show strong bactericidal activity. When contact time with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) of 105 colony forming units (CFU)/mL exceeded 3 h, the bactericidal rates of the four different silver content ceramics against E. coli and S. aureus were all 100%. Strong bactericidal effect against E. coli with initial concentration of 109 CFU/mL were also observed in ceramic newly obtained and ceramic immersed in water for 270 days, demonstrating its high stability. The silver-diatomite nanocomposite ceramic filters could be a promising candidate for point-of-use water treatment.

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Phytosynthetic Fabrication of Lanthanum Ion-Doped Nickel Oxide Nanoparticles Using Sesbania grandiflora Leaf Extract and Their Anti-Microbial Properties

Crystals ◽

10.3390/cryst11020124 ◽

2021 ◽

Vol 11 (2) ◽

pp. 124

Author(s):

Srihasam Saiganesh ◽

Thyagarajan Krishnan ◽

Golla Narasimha ◽

Hesham S. Almoallim ◽

Sulaiman Ali Alhari ◽

...

Keyword(s):

Electron Microscopy ◽

Optical Properties ◽

Rare Earth ◽

Nickel Oxide ◽

Photoelectron Spectroscopy ◽

Metal Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Nio Nanoparticles ◽

X Ray ◽

Sesbania Grandiflora

Over the past few years, the photogenic fabrication of metal oxide nanoparticles has attracted considerable attention, owing to the simple, eco-friendly, and non-toxic procedure. Herein, we fabricated NiO nanoparticles and altered their optical properties by doping with a rare earth element (lanthanum) using Sesbania grandiflora broth for antibacterial applications. The doping of lanthanum with NiO was systematically studied. The optical properties of the prepared nanomaterials were investigated through UV-Vis diffuse reflectance spectra (UV-DRS) analysis, and their structures were studied using X-ray diffraction analysis. The morphological features of the prepared nanomaterials were examined by scanning electron microscopy and transmission electron microscopy, their elemental structure was analyzed by energy-dispersive X-ray spectral analysis, and their oxidation states were analyzed by X-ray photoelectron spectroscopy. Furthermore, the antibacterial action of NiO and La-doped NiO nanoparticles was studied by the zone of inhibition method for Gram-negative and Gram-positive bacterial strains such as Escherichia coli and Bacillus sublitis. It was evident from the obtained results that the optimized compound NiOLa-04 performed better than the other prepared compounds. To the best of our knowledge, this is the first report on the phytosynthetic fabrication of rare-earth ion Lanthanum (La3+)-doped Nickel Oxide (NiO) nanoparticles and their anti-microbial studies.

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