A TiO2 Coated Carbon Aerogel Derived from Bamboo Pulp Fibers for Enhanced Visible Light Photo-Catalytic Degradation of Methylene Blue

Carbon aerogels (CA) derived from bamboo cellulose fibers were coupled with TiO2 to form CA/TiO2 hybrids, which exhibited extraordinary performance on the photo-catalytic degradation of methylene blue (MB). The structure and morphology of CA/TiO2 were characterized by field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Raman spectrum. The CA displayed a highly porous and interconnected three-dimensional framework structure, while introducing the catalytic active sites of TiO2 onto the aerogel scaffold could remarkably enhance its photo-catalytic activity. The adsorption and photo-catalytic degradation of MB by the CA/TiO2 hybrid were investigated. The maximum adsorption capacity of CA/TiO2 for MB was 18.5 mg/g, which outperformed many similar materials reported in the literature. In addition, compared with other photo-catalysts, the present CA/TiO2 demonstrated superior photo-catalytic performance. Almost 85% of MB in 50 mL solution with a MB concentration of 10 mg/L could be effectively degraded by 15 mg CA/TiO2 in 300 min.

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Efficient Adsorption of Methylene Blue by Porous Biochar Derived from Soybean Dreg Using a One-Pot Synthesis Method

Molecules ◽

10.3390/molecules26030661 ◽

2021 ◽

Vol 26 (3) ◽

pp. 661

Author(s):

Zhiwei Ying ◽

Xinwei Chen ◽

He Li ◽

Xinqi Liu ◽

Chi Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Methylene Blue ◽

Photoelectron Spectroscopy ◽

Synthesis Method ◽

Urban Pollution ◽

Maximum Adsorption Capacity ◽

One Pot ◽

Average Pore ◽

X Ray ◽

Isotherm Equation

Soybean dreg is a by-product of soybean products production, with a large consumption in China. Low utilization value leads to random discarding, which is one of the important sources of urban pollution. In this work, porous biochar was synthesized using a one-pot method and potassium bicarbonate (KHCO3) with low-cost soybean dreg (SD) powder as the carbon precursor to investigating the adsorption of methylene blue (MB). The prepared samples were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), elemental analyzer (EA), Brunauer-Emmett-Teller (BET), X-ray diffractometer (XRD), Raman spectroscopy (Raman), Fourier transform infrared spectrometer (FTIR), and X-ray photoelectron spectroscopy (XPS). The obtained SDB-K-3 showed a high specific surface area of 1620 m2 g−1, a large pore volume of 0.7509 cm3 g−1, and an average pore diameter of 1.859 nm. The results indicated that the maximum adsorption capacity of SDB-K-3 to MB could reach 1273.51 mg g−1 at 318 K. The kinetic data were most consistent with the pseudo-second-order model and the adsorption behavior was more suitable for the Langmuir isotherm equation. This study demonstrated that the porous biochar adsorbent can be prepared from soybean dreg by high value utilization, and it could hold significant potential for dye wastewater treatment in the future.

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Facile Preparation of Rod-like MnO Nanomixtures via Hydrothermal Approach and Highly Efficient Removal of Methylene Blue for Wastewater Treatment

Nanomaterials ◽

10.3390/nano9010010 ◽

2018 ◽

Vol 9 (1) ◽

pp. 10 ◽

Cited By ~ 37

Author(s):

Yuelong Xu ◽

Bin Ren ◽

Ran Wang ◽

Lihui Zhang ◽

Tifeng Jiao ◽

...

Keyword(s):

Electron Microscopy ◽

Methylene Blue ◽

Photoelectron Spectroscopy ◽

Degradation Mechanism ◽

Dye Adsorption ◽

Maximum Adsorption Capacity ◽

X Ray ◽

Transmission Electron ◽

Degradation Ratio ◽

Hydrothermal Approach

In the present study, nanoscale rod-shaped manganese oxide (MnO) mixtures were successfully prepared from graphitic carbon nitride (C3N4) and potassium permanganate (KMnO4) through a hydrothermal method. The as-prepared MnO nanomixtures exhibited high activity in the adsorption and degradation of methylene blue (MB). The as-synthesized products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), surface area analysis, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Furthermore, the effects of the dose of MnO nanomixtures, pH of the solution, initial concentration of MB, and the temperature of MB removal in dye adsorption and degradation experiments was investigated. The degradation mechanism of MB upon treatment with MnO nanomixtures and H2O2 was studied and discussed. The results showed that a maximum adsorption capacity of 154 mg g−1 was obtained for a 60 mg L−1 MB solution at pH 9.0 and 25 °C, and the highest MB degradation ratio reached 99.8% under the following optimum conditions: 50 mL of MB solution (20 mg L−1) at room temperature and pH ≈ 8.0 with 7 mg of C, N-doped MnO and 0.5 mL of H2O2.

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Capping Agent Effect on Pd-Supported Nanoparticles in the Hydrogenation of Furfural

Catalysts ◽

10.3390/catal10010011 ◽

2019 ◽

Vol 10 (1) ◽

pp. 11 ◽

Cited By ~ 3

Author(s):

Shahram Alijani ◽

Sofia Capelli ◽

Stefano Cattaneo ◽

Marco Schiavoni ◽

Claudio Evangelisti ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Active Sites ◽

Catalytic Performance ◽

Shielding Effect ◽

Capping Agents ◽

X Ray ◽

Supported Nanoparticles ◽

Liquid Phase Hydrogenation ◽

Diallyldimethylammonium Chloride ◽

Transmission Electron

The catalytic performance of a series of 1 wt % Pd/C catalysts prepared by the sol-immobilization method has been studied in the liquid-phase hydrogenation of furfural. The temperature range studied was 25–75 °C, keeping the H2 pressure constant at 5 bar. The effect of the catalyst preparation using different capping agents containing oxygen or nitrogen groups was assessed. Polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and poly (diallyldimethylammonium chloride) (PDDA) were chosen. The catalysts were characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The characterization data suggest that the different capping agents affected the initial activity of the catalysts by adjusting the available Pd surface sites, without producing a significant change in the Pd particle size. The different activity of the three catalysts followed the trend: PdPVA/C > PdPDDA/C > PdPVP/C. In terms of selectivity to furfuryl alcohol, the opposite trend has been observed: PdPVP/C > PdPDDA/C > PdPVA/C. The different reactivity has been ascribed to the different shielding effect of the three ligands used; they influence the adsorption of the reactant on Pd active sites.

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A facile method to fabricate AC/CuO for efficient removal of organic pollutants by adsorption and persulfate-based advanced oxidation processes

Journal of Water Supply Research and Technology—AQUA ◽

10.2166/aqua.2020.094 ◽

2020 ◽

Author(s):

Youlin Li ◽

Yu Hu ◽

Wenqiao You ◽

Guangming Zhou ◽

Guilong Peng

Keyword(s):

Catalytic Performance ◽

Catalytic Degradation ◽

Maximum Adsorption Capacity ◽

Efficient Removal ◽

X Ray ◽

One Step ◽

Ft Ir ◽

Degradation Reaction ◽

The Relationship ◽

Insight Into

Abstract Activated carbon/CuO (AC/CuO) composites was prepared through a facile one-step hydrothermal method and used as a bifunctional material for adsorption and catalysis degradation of bisphenol A (BPA). The composite was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray powder diffraction (XRD). The obtained AC/CuO exhibited excellent adsorption and catalytic performance. The maximum adsorption capacity of BPA on the AC/CuO was 319.03 mg/g according to the Langmuir fitting. At an initial BPA concentration of 20 mg/L, the BPA degradation efficiencies were maintained above 96% for 15 min by using 20 mg/L AC/CuO and 2 mM peroxymonosulfate (PMS). Moreover, the relationship between adsorption and catalytic degradation was also investigated. The results indicated that the pre-adsorption disfavored the degradation reaction. This work not only provides a novel preparation method for AC/CuO catalyst, but also gives a deeper insight into the mechanisms between adsorption and catalytic degradation.

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The three-dimensional flower-like Bi 2 WO 6 assisted by ethanolamine through a microwave method for efficient photocatalytic activity

Royal Society Open Science ◽

10.1098/rsos.181422 ◽

2019 ◽

Vol 6 (3) ◽

pp. 181422

Author(s):

Xingchen Liu ◽

SuZhen Wang ◽

Song Wang ◽

Han Shi ◽

Xiaolong Zhang ◽

...

Keyword(s):

Photocatalytic Activity ◽

Photoelectron Spectroscopy ◽

Three Dimensional ◽

Catalytic Performance ◽

Microwave Method ◽

Photocatalytic Efficiency ◽

X Ray Diffraction ◽

Structure Directing Agent ◽

X Ray ◽

One Step

The three-dimensional flower-like Bi 2 WO 6 was synthesized through a one-step microwave method (the reaction temperature was 434 K and the reaction took 10 min) with the assistance of ethanolamine (EA). The prepared samples were characterized by X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, ultraviolet–visible spectroscopy, PL, X-ray photoelectron spectroscopy and Brunauer–Emmett–Teller analysis. Methyl orange was used as target pollutant to evaluate the photocatalysis property of samples. Furthermore, the influence of the mechanism of EA on the structure and catalytic performance of Bi 2 WO 6 was discussed. The detailed characterizations revealed that the three-dimensional flower-like Bi 2 WO 6 was successfully synthesized with the assistance of EA. The results confirmed that EA significantly influenced the morphology of Bi 2 WO 6 products. The addition of EA can effectively alter the pressure of the reaction and improve the crystal phase and structure of Bi 2 WO 6 photocatalysts, enhancing the photocatalytic activity of samples and improving the photocatalytic efficiency. EA can serve as an assembling agent and structure-directing agent resulting in the formation of flower-like architectures. With the increase of the amount of EA, the as-prepared Bi 2 WO 6 sample gradually forms a flower-like structure, leading to a shorter time of light holes migrating to the surface of the catalyst. It makes the compound rate significantly decreased, and improves the photocatalytic efficiency of the sample.

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Nitrogen-Doped Carbon Aerogels Derived from Starch Biomass with Improved Electrochemical Properties for Li-Ion Batteries

International Journal of Molecular Sciences ◽

10.3390/ijms22189918 ◽

2021 ◽

Vol 22 (18) ◽

pp. 9918

Author(s):

Marcelina Kubicka ◽

Monika Bakierska ◽

Krystian Chudzik ◽

Michał Świętosławski ◽

Marcin Molenda

Keyword(s):

Electrochemical Properties ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Potato Starch ◽

Specific Capacity ◽

Carbon Aerogel ◽

Carbon Aerogels ◽

Modern World ◽

X Ray ◽

Li Ion

Among all advanced anode materials, graphite is regarded as leading and still-unrivaled. However, in the modern world, graphite-based anodes cannot fully satisfy the customers because of its insufficient value of specific capacity. Other limitations are being nonrenewable, restricted natural graphite resources, or harsh conditions required for artificial graphite production. All things considered, many efforts have been made in the investigation of novel carbonaceous materials with desired properties produced from natural, renewable resources via facile, low-cost, and environmentally friendly methods. In this work, we obtained N-doped, starch-based carbon aerogels using melamine and N2 pyrolysis as the source of nitrogen. The materials were characterized by X-ray powder diffraction, elemental analysis, X-ray photoelectron spectroscopy, galvanostatic charge–discharge tests, cyclic voltammetry, and electrochemical impedance spectroscopy. Depending on the doping method and the nitrogen amount, synthesized samples achieved different electrochemical behavior. N-doped, bioderived carbons exhibit far better electrochemical properties in comparison with pristine ones. Materials with the optimal amount of nitrogen (such as MCAGPS-N8.0%—carbon aerogel made from potato starch modified with melamine and CAGPS-N1.2%—carbon aerogel made from potato starch modified by N2 pyrolysis) are also competitive to graphite, especially for high-performance battery applications. N-doping can enhance the efficiency of Li-ion cells mostly by inducing more defects in the carbon matrix, improving the binding ability of Li+ and charge-transfer process.

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Operando high-pressure investigation of size-controlled CuZn catalysts for the methanol synthesis reaction

Nature Communications ◽

10.1038/s41467-021-21604-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Núria J. Divins ◽

David Kordus ◽

Janis Timoshenko ◽

Ilya Sinev ◽

Ioannis Zegkinoglou ◽

...

Keyword(s):

High Pressure ◽

Photoelectron Spectroscopy ◽

Active Sites ◽

Surface Segregation ◽

Ambient Pressure ◽

Catalytic Performance ◽

Oxide Interface ◽

X Ray ◽

Oxide Support ◽

Open Questions

AbstractAlthough Cu/ZnO-based catalysts have been long used for the hydrogenation of CO2 to methanol, open questions still remain regarding the role and the dynamic nature of the active sites formed at the metal-oxide interface. Here, we apply high-pressure operando spectroscopy methods to well-defined Cu and Cu0.7Zn0.3 nanoparticles supported on ZnO/Al2O3, γ-Al2O3 and SiO2 to correlate their structure, composition and catalytic performance. We obtain similar activity and methanol selectivity for Cu/ZnO/Al2O3 and CuZn/SiO2, but the methanol yield decreases with time on stream for the latter sample. Operando X-ray absorption spectroscopy data reveal the formation of reduced Zn species coexisting with ZnO on CuZn/SiO2. Near-ambient pressure X-ray photoelectron spectroscopy shows Zn surface segregation and the formation of a ZnO-rich shell on CuZn/SiO2. In this work we demonstrate the beneficial effect of Zn, even in diluted form, and highlight the influence of the oxide support and the Cu-Zn interface in the reactivity.

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MOFs-Derived Zn-Based Catalysts in Acetylene Acetoxylation

Nanomaterials ◽

10.3390/nano12010098 ◽

2021 ◽

Vol 12 (1) ◽

pp. 98

Author(s):

Mengli Li ◽

Zhuang Xu ◽

Yuhao Chen ◽

Guowang Shen ◽

Xugen Wang ◽

...

Keyword(s):

Catalytic Activity ◽

Photoelectron Spectroscopy ◽

Active Sites ◽

Metal Organic Frameworks ◽

Catalytic Performance ◽

Electron Cloud ◽

Nitrogen Gas ◽

X Ray ◽

Metal Organic ◽

Cloud Density

Metal–organic frameworks (MOFs)-derived materials with a large specific surface area and rich pore structures are favorable for catalytic performance. In this work, MOFs are successfully prepared. Through pyrolysis of MOFs under nitrogen gas, zinc-based catalysts with different active sites for acetylene acetoxylation are obtained. The influence of the oxygen atom, nitrogen atom, and coexistence of oxygen and nitrogen atoms on the structure and catalytic performance of MOFs-derived catalysts was investigated. According to the results, the catalysts with different catalytic activity are Zn-O-C (33%), Zn-O/N-C (27%), and Zn-N-C (12%). From the measurements of X-ray photoelectron spectroscopy (XPS), it can be confirmed that the formation of different active sites affects the electron cloud density of zinc. The electron cloud density of zinc affects the ability to attract CH3COOH, which makes catalysts different in terms of catalytic activity.

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Preparation of a Series of Pd@UIO-66 by a Double-Solvent Method and Its Catalytic Performance for Toluene Oxidation

Materials ◽

10.3390/ma13010088 ◽

2019 ◽

Vol 13 (1) ◽

pp. 88 ◽

Cited By ~ 2

Author(s):

Chuanying Wei ◽

Haili Hou ◽

Ermo Wang ◽

Min Lu

Keyword(s):

Photoelectron Spectroscopy ◽

Active Sites ◽

Catalytic Properties ◽

Catalytic Performance ◽

Adsorbed Oxygen ◽

Large Specific Surface Area ◽

Toluene Oxidation ◽

X Ray ◽

Solvent Method ◽

Transmission Electron

This paper reports on the preparation, characterization, and catalytic properties of the Pd@UIO-66 for toluene oxidation. The samples are prepared by the double-solvent method to form catalysts with large specific surface area, highly dispersed Pd0 (Elemental palladium) and abundant adsorbed oxygen, which are characterized by X-ray Photoelectron Spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and Transmission Electron Microscopy (TEM). The results show that as the Pd content increases, the adsorbed oxygen content further increases, but at the same time Pd0 will agglomerate and lose some active sites, which will affect its catalytic performance. While 0.2%Pd@UIO-66 has the highest concentration of Pd0, the result shows it has the best catalytic activity and the T90 temperature is 210 °C.

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Elemental Mercury Adsorption by Cupric Chloride-Modified Mesoporous Carbon Aerogel

Colloids and Interfaces ◽

10.3390/colloids2040066 ◽

2018 ◽

Vol 2 (4) ◽

pp. 66 ◽

Cited By ~ 2

Author(s):

Dongjing Liu ◽

Cheng Lu ◽

Jiang Wu

Keyword(s):

Removal Efficiency ◽

Photoelectron Spectroscopy ◽

Mesoporous Carbon ◽

Copper Chloride ◽

Elemental Mercury ◽

Carbon Aerogel ◽

Carbon Aerogels ◽

Mercury Adsorption ◽

X Ray ◽

Good Ability

Mesoporous carbon aerogels (MCA) synthesized via aqueous polymerization of resorcinol and formaldehyde were modified by copper chloride and applied for adsorption removal of elemental mercury (Hg0) at a low temperature. The sorbents were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), nitrogen adsorption/desorption isotherms, and X-ray photoelectron spectroscopy (XPS) techniques. The results show that CuCl2-modified MCA exhibited good ability for Hg0 adsorption in the 40–160 °C temperature range, with Hg0 removal efficiency all above 95.0%. The Hg0 removal efficiency first increased and then decreased with the elevation of reaction temperature. It performed optimally at 80 °C with the highest Hg0 removal efficiency of 98.7%. XPS results indicate that covalent chlorines (C-Cl groups) play an important role in elemental mercury adsorption process. Hg0 is firstly captured in the form of oxidized mercury (Hg2+) and then reacts with C-Cl groups to form HgCl2.

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