The Preparation of Pd/Foam-Ni Electrode and Its Electrocatalytic Hydrodechlorination for Monochlorophenol Isomers

Noble metal palladium modified foamed nickel electrode (Pd/foam-Ni) was prepared by electrodeposition method. The fabricated electrode showed better catalytic performance than the Pd/foam-Ni prepared by conventional electroless deposition. The catalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Electrocatalytic activity of the Pd/Ni was studied for the hydrodechlorination of monochlorophenol isomers. The Pd/Ni exhibited good catalytic activity for 3-chlorophenol (3-CP). Complete decomposition of chlorophenol isomers could be achieved within 2 h, and the hydrodechlorination process conformed to the pseudo-first-order kinetic model. It showed a supreme stability after recycling for 5 times. The Pd/Ni exhibited a promising application prospect with high effectiveness and low Pd loading.

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Preparation of g-C3N4/MoS2 Composite Material and Its Visible Light Catalytic Performance

10.21203/rs.3.rs-627855/v1 ◽

2021 ◽

Author(s):

Yu Fan ◽

Yan-ning Yang ◽

Chen Ding

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Visible Light ◽

Photoelectron Spectroscopy ◽

Photogenerated Electron ◽

Catalytic Performance ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Calcination Method

Abstract The g-C3N4 nanosheet was prepared by calcination method, the MoS2 nanosheet was prepared by hydrothermal method. The g-C3N4/MoS2 composites were prepared by ultrasonic composite in anhydrous ethanol. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV-Vis), and photoluminescence (PL) techniques were used to characterize the materials. The photocatalytic degradation of Rhodamine B (Rh B) by g-C3N4/MoS2 composites with different mass ratios was investigated under visible light. The results show that a small amount of MoS2 combined with g-C3N4 can significantly improve photocatalytic activity. The g-C3N4/MoS2 composite with a mass ratio of 1:8 has the highest photocatalytic activity, and the degradation rate of Rh B increases from 50% to 99.6%. The main reason is that MoS2 and g-C3N4 have a matching band structure. The separation rate of photogenerated electron-hole pairs is enhanced. So the g-C3N4/MoS2 composite can improve the photocatalytic activity. The photocatalytic mechanism was proposed through the active matter capture experiment.

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Selective Catalytic Reduction of NOx with NH3 over Mn2O3 supported with different morphology of CeO2 Catalysts

10.22541/au.163452243.37004611/v1 ◽

2021 ◽

Author(s):

Shyam Rao ◽

VIVEK PATEL ◽

Sweta Sharma

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Catalytic Reduction ◽

Catalytic Performance ◽

X Ray Diffraction ◽

Wet Impregnation ◽

X Ray ◽

Nh3 Scr ◽

Transmission Electron ◽

Reduction Of Nox

Three different morphologies of CeO2 supports (NP, NC, and NR) were prepared by hydrothermal method and further Mn2O3 is impregnated on CeO2 supports using wet-impregnation methods, and their activity for NO reduction using NH3-SCR technique is analysed. The prepared catalysts and supports are further characterized through scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and transmission electron microscopy (TEM), and Brunauer–Emmett–Teller (BET). The catalytic performance of Mn2O3/CeO2-NP has shown the highest conversion (76.06 %) compared to the other two catalysts in the temperature range of 50 - 450°C.

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Novel CuO/Mn3O4/ZnO nanocomposite with superior photocatalytic activity for removal of Rabeprazole from water

Scientific Reports ◽

10.1038/s41598-021-94066-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sauvik Raha ◽

Dipyaman Mohanta ◽

Md. Ahmaruzzaman

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Photoelectron Spectroscopy ◽

Oxygen Demand ◽

Order Kinetic ◽

Liquid Chromatograph ◽

X Ray ◽

Transmission Electron ◽

Order Kinetic Model

AbstractIn this work, a nanohybrid of CuO/Mn3O4/ZnO was generated through a simple hydrothermal based procedure. The CuO/Mn3O4/ZnO nanohybrid has been characterized using X-ray diffraction, transmission electron microscopy high resolution transmission electron microscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive X-ray analysis. UV–visible spectrophotometry and photoluminescence techniques allowed evaluation of optical properties that additionally suggested the prevalence of strong interfacial interaction between the three moieties of the nanohybrid and suppressed electron–hole recombination. The hybrid photocatalyst brought on ~ 97.02 ± 1.15% disintegration of rabeprazole when illuminated with visible light. The progress of the photodegradation was in conformity with pseudo-first order kinetic model and had a velocity constant of 0.07773 min−1. Additionally, ~ 84.45% of total organic carbon removal was achieved while chemical oxygen demand was reduced by ~ 73.01%. Using high resolution liquid chromatograph mass spectrometry technique, identification of the degraded products was made and accordingly the mechanistic route of the aforesaid degradation was proposed.

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Synthesis of Ce1−xPdxO2−δ Solid Solution in Molten Nitrate

Catalysts ◽

10.3390/catal10060640 ◽

2020 ◽

Vol 10 (6) ◽

pp. 640

Author(s):

Hideaki Sasaki ◽

Keisuke Sakamoto ◽

Masami Mori ◽

Tatsuaki Sakamoto

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Solid Solutions ◽

Photoelectron Spectroscopy ◽

Synthesis Method ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Co Precipitation ◽

Ionic States

CeO2-based solid solutions in which Pd partially substitutes for Ce attract considerable attention, owing to their high catalytic performances. In this study, the solid solution (Ce1−xPdxO2−δ) with a high Pd content (x ~ 0.2) was synthesized through co-precipitation under oxidative conditions using molten nitrate, and its structure and thermal decomposition were examined. The characteristics of the solid solution, such as the change in a lattice constant, inhibition of sintering, and ionic states, were examined using X-ray diffraction (XRD), scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM−EDS), transmission electron microscopy (TEM)−EDS, and X-ray photoelectron spectroscopy (XPS). The synthesis method proposed in this study appears suitable for the easy preparation of CeO2 solid solutions with a high Pd content.

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Enhanced Photocatalytic Activity of Cu2O Cabbage/RGO Nanocomposites under Visible Light Irradiation

Polymers ◽

10.3390/polym13111712 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1712

Author(s):

Appusamy Muthukrishnaraj ◽

Salma Ahmed Al-Zahrani ◽

Ahmed Al Otaibi ◽

Semmedu Selvaraj Kalaivani ◽

Ayyar Manikandan ◽

...

Keyword(s):

Electron Microscopy ◽

Thermo Gravimetric Analysis ◽

Visible Region ◽

Catalytic Performance ◽

Precipitation Method ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Dye Pollutants ◽

Transmission Electron

Towards the utilization of Cu2O nanomaterial for the degradation of industrial dye pollutants such as methylene blue and methyl orange, the graphene-incorporated Cu2O nanocomposites (GCC) were developed via a precipitation method. Using Hummers method, the grapheme oxide (GO) was initially synthesized. The varying weight percentages (1–4 wt %) of GO was incorporated along with the precipitation of Cu2O catalyst. Various characterization techniques such as Fourier-transform infra-red (FT-IR), X-ray diffraction (XRD), UV–visible diffused reflectance (UV-DRS), Raman spectroscopy, thermo gravimetric analysis (TGA), energy-dispersive X-ray analysis (EDX), and electro chemical impedance (EIS) were followed for characterization. The cabbage-like morphology of the developed Cu2O and its composites were ascertained from field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HR-TEM). In addition, the growth mechanism was also proposed. The results infer that 2 wt % GO-incorporated Cu2O composites shows the highest value of degradation efficiency (97.9% and 96.1%) for MB and MO at 160 and 220 min, respectively. Further, its catalytic performance over visible region (red shift) was also enhanced to an appreciable extent, when compared with that of other samples.

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Aluminum Nitride-Silicon Carbide Alloy Crystals Grown on SiC Substrates by Sublimation

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300000569 ◽

2005 ◽

Vol 10 ◽

Cited By ~ 6

Author(s):

Z. Gu ◽

L. Du ◽

J.H. Edgar ◽

E.A. Payzant ◽

L. Walker ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

X Ray Diffraction ◽

Original Source ◽

X Ray ◽

Alloy Crystal ◽

Transmission Electron ◽

Crystal Substrate ◽

Vapor Distribution ◽

Uniform Composition

AlN-SiC alloy crystals, with a thickness greater than 500 µm, were grown on 4H- and 6H-SiC substrates from a mixture of AlN and SiC powders by the sublimation-recondensation method at 1860-1990 °C. On-axis SiC substrates produced a rough surface covered with hexagonal grains, while 6H- and 4H- off-axis SiC substrates with different miscut angles (8° or 3.68°) formed a relatively smooth surface with terraces and steps. The substrate misorientation ensured that the AlN-SiC alloy crystals grew two dimensionally as identified by scanning electron microscopy (SEM). X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed that the AlN-SiC alloys had the wurtzite structure. Electron probe microanalysis (EPMA) and x-ray photoelectron spectroscopy (XPS) demonstrated that the resultant alloy crystals had non-stoichiometric ratios of Al:N and Si:C and a uniform composition throughout the alloy crystal from the interface to the surface. The composition ratio of Al:Si of the alloy crystals changed with the growth temperature, and differed from the original source composition, which was consistent with the results predicted by thermodynamic calculation of the solid-vapor distribution of each element. XPS detected the bonding between Si-C, Si-N, Si-O for the Si 2p spectra. The dislocation density decreased with the growth, which was lower than 106 cm−2 at the alloy surface, more than two orders of magnitude lower compared to regions close to the crystal/substrate interface, as determined by TEM.

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Synthesis of Three-Dimensional Fe3O4/Graphene Aerogels for the Removal of Arsenic Ions from Water

Journal of Nanomaterials ◽

10.1155/2015/864864 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 10

Author(s):

Yan Ye ◽

Da Yin ◽

Bin Wang ◽

Qingwen Zhang

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

3D Structure ◽

Three Dimensional ◽

X Ray Diffraction ◽

X Ray ◽

Graphene Aerogels ◽

Transmission Electron ◽

Potential Applications ◽

Removal Of Arsenic

We report the synthesis of three-dimensional Fe3O4/graphene aerogels (GAs) and their application for the removal of arsenic (As) ions from water. The morphology and properties of Fe3O4/GAs have been characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and superconducting quantum inference device. The 3D nanostructure shows that iron oxide nanoparticles are decorated on graphene with an interconnected network structure. It is found that Fe3O4/GAs own a capacity of As(V) ions adsorption up to 40.048 mg/g due to their remarkable 3D structure and existence of magnetic Fe3O4nanoparticles for separation. The adsorption isotherm matches well with the Langmuir model and kinetic analysis suggests that the adsorption process is pseudo-second-ordered. In addition to the excellent adsorption capability, Fe3O4/GAs can be easily and effectively separated from water, indicating potential applications in water treatment.

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Microwave-assisted preparation of ZnS and ZnSe nanocrystals with different morphologies for photodegradation process of organic dyes

Proceedings 17th International Conference on Microwave and High Frequency Heating ◽

10.4995/ampere2019.2019.9998 ◽

2019 ◽

Author(s):

Katarzyna Matras-Postolek ◽

A. Zaba ◽

S. Sovinska ◽

D. Bogdal

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Organic Dyes ◽

Zinc Sulphide ◽

Conventional Heating ◽

Bet Surface Area ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy

Zinc sulphide (ZnS) and zinc selenide (ZnSe) and manganese-doped and un-doped with different morphologies from 1D do 3D microflowers were successfully fabricated in only a few minutes by solvothermal reactions under microwave irradiation. In order to compare the effect of microwave heating on the properties of obtained nanocrystals, additionally the synthesis under conventional heating was conducted additionally in similar conditions. The obtained nanocrystals were systematically characterized in terms of structural and optical properties using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance UV-Vis spectroscopy (DR UV-Vis), Fourier-transform infrared spectroscopy (FT-IR), photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area analysis. The photocatalytic activity of ZnSe, ZnS, ZnS:Mn and ZnSe:Mn nanocrystals with different morphologies was evaluated by the degradation of methyl orange (MO) and Rhodamine 6G (R6G), respectively. The results show that Mn doped NCs samples had higher coefficient of degradation of organic dyes under ultraviolet irradiation (UV).

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Synthesis and characterization of homogeneous lead-substituted tin oxide with the (110) face of rutile structure

Journal of Materials Research ◽

10.1557/jmr.2000.0298 ◽

2000 ◽

Vol 15 (10) ◽

pp. 2076-2079

Author(s):

Chika Nozaki ◽

Takashi Yamada ◽

Kenji Tabata ◽

Eiji Suzuki

Keyword(s):

Electron Microscopy ◽

Tin Oxide ◽

Photoelectron Spectroscopy ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

Rutile Structure ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

Synthesis of a rutile-type lead-substituted tin oxide with (110) face was investigated. The characterization was performed by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, infrared spectroscopy, x-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller surface area measurements. The homogeneous rutile-type lead-substituted tin oxide was obtained until 4.1 mol% of tin was substituted with lead. The surface of obtained oxide had a homogeneously lead-substituted (110) face.

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Biomass-Derived Activated Carbon as a Catalyst for the Effective Degradation of Rhodamine B dye

Processes ◽

10.3390/pr8080926 ◽

2020 ◽

Vol 8 (8) ◽

pp. 926

Author(s):

Shamim Ahmed Hira ◽

Mohammad Yusuf ◽

Dicky Annas ◽

Hu Shi Hui ◽

Kang Hyun Park

Keyword(s):

Electron Microscopy ◽

Activated Carbon ◽

Rhodamine B ◽

Photoelectron Spectroscopy ◽

High Specific Surface Area ◽

High Porosity ◽

X Ray Diffraction ◽

Experimental Conditions ◽

X Ray ◽

Transmission Electron

Activated carbon (AC) was fabricated from carrot waste using ZnCl2 as the activating agent and calcined at 700 °C for 2 h in a tube furnace. The as-synthesized AC was characterized using Fourier-transform infrared spectroscopy, X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller analysis; the results revealed that it exhibited a high specific surface area and high porosity. Moreover, this material displayed superior catalytic activity for the degradation of toxic Rhodamine B (RhB) dye. Rate constant for the degradation of RhB was ascertained at different experimental conditions. Lastly, we used the Arrhenius equation and determined that the activation energy for the decomposition of RhB using AC was approximately 35.9 kJ mol−1, which was very low. Hopefully it will create a great platform for the degradation of other toxic dye in near future.

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