Green synthesis of CuO/rGO nanocomposite using Terminalia Arjuna bark extract and its catalytic activity for purification of water

The authors report the preparation of the nanocomposite comprising of vanadium pentoxide (V2O5) and selenium (Se) nanoparticles and functionalized multiwalled carbon nanotubes (MWCNTs) (V2O5@Se NPs/MWCNTs). Since Se NPs possesses extraordinary physicochemical properties including larger surface area with higher adsorption capacity, V2O5 NPs were adsorbed onto Se NPs surface through physisorption process (designated as V2O5@Se NPs). The nanocomposite synthesized hydrothermally was evaluated for its antimicrobial activity. The morphology and microstructure of the nanocomposite were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis, respectively. Fourier transform infrared spectroscopy (FTIR) and UV-Visible spectroscopy (UV-Vis) were employed to analyze the spectral properties of nanocomposite. The microbicidal efficacy of nanocomposite was tested against Gram-negative (G-)ZGram-positive (G+) bacteria and fungus. This is the first report on the synthesis of V2O5@Se NPs/MWCNTs nanocomposites by chemical method that showed microbicidal effect on micro-organisms. The thiol (-SH) units facilitates the enrichment of V2O5@Se NPs onto MWCNTs surface. Ultimately, it reflects on the significant antimicrobial activity of V2O5@Se NPs/MWCNTs.

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Effect of Re and Tm-site on morphology structure and optical band gap of ReTmO3 (Re: La, Ce, Nd, Gd, Dy, Y and Tm: Fe, Cr) prepared by sol-gel method

Revista Mexicana de Física ◽

10.31349/revmexfis.64.381 ◽

2018 ◽

Vol 64 (4) ◽

pp. 381

Author(s):

Muhammad Tufiq Jamil ◽

Javed Ahmad ◽

Syed Hamad Bukhari ◽

Murtaza Saleem

Keyword(s):

Band Gap ◽

Sol Gel ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

Orthorhombic Crystal ◽

X Ray ◽

Average Grain Size ◽

Auto Combustion ◽

Uv Visible

Rare earth nano sized pollycrystalline orthoferrites and orthocromites ReT mO3 (Re = La, Nd, Gd, Dy, Y and T m = Fe, Cr) have been synthesized by sol-gel auto combustion citrate method. The samples have been characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), and UV-visible spectroscopy. The samples are single phase as confirmed by XRD analysis and correspond to the orthorhombic crystal symmetry with space group pbnm. Debye Scherer formula and Williamson Hall analysis have been used to calculate the average grain size which is consistent with that of determined from SEM analysis and varied between 25-75 nm. The elemental compositions of all samples have been checked by EDX analysis. Different crystallographic parameters are calculated with strong structural correlation among Re and Tm sites. The optical energy band gap has been calculated by using Tauc relation estimated to be in the range of 1.77 - 1.87 eV and 2.77 - 3.14 eV, for ReFeO3 and ReCrO3, respectively.

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Hierarchical Nanostructured ZnO-CuO Nanocomposite and its Photocatalytic Activity

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.35.21 ◽

2015 ◽

Vol 35 ◽

pp. 21-26 ◽

Cited By ~ 16

Author(s):

Susmita Das ◽

Vimal Chandra Srivastava

Keyword(s):

Photocatalytic Activity ◽

Pure Copper ◽

Ultra Violet ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Ultra Violet Radiation ◽

One Step ◽

Uv Visible

Metal oxide nanocomposite (ZnO-CuO) was successfully synthesized by one step homogeneous coprecipitation method and further characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron micrograph (SEM), X-ray diffraction analysis (XRD) and UV-visible diffuse reflectance spectra. XRD analysis exhibited presence of pure copper oxide and zinc oxide within the nanocomposite. SEM analysis indicated that the ZnO-CuO nanocomposite was consisted of flower shaped ZnO along with leaf shaped CuO. Photocatalytic activity of nanocomposite was evaluated in terms of degradation of methylene blue (MB) dye solution under ultra-violet radiation. Results showed that the photocatalytic efficiency of ZnO-CuO nanocomposite was higher than its individual pure oxides (ZnO or CuO).

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Novel NiMgOH-rGO-Based Nanostructured Hybrids for Electrochemical Energy Storage Supercapacitor Applications: Effect of Reducing Agents

Crystals ◽

10.3390/cryst11091144 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1144

Author(s):

Konda Shireesha ◽

Thida Rakesh Kumar ◽

Tumarada Rajani ◽

Chidurala Shilpa Chakra ◽

Murikinati Mamatha Kumari ◽

...

Keyword(s):

Particle Size ◽

Cyclic Voltammetry ◽

Fourier Transform ◽

Infrared Spectroscopy ◽

Fourier Transform Infrared Spectroscopy ◽

X Ray Diffraction ◽

Visible Spectroscopy ◽

X Ray ◽

Particle Size Analyzer ◽

Uv Visible

This paper describes the synthesis and characterization of NiMgOH-rGO nanocomposites made using a chemical co-precipitation technique with various reducing agents (e.g., NaOH and NH4OH) and reduced graphene oxide at 0.5, 1, and 1.5 percent by weight. UV-visible spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, a particle size analyzer, and cyclic voltammetry were used to characterize the composite materials. The formation of the NiMgOH-rGO nanocomposite with crystallite sizes in the range of 10–40 nm was inferred by X-ray diffraction patterns of materials, which suggested interlayers of Ni(OH)2 and Mg(OH)2. The interactions between the molecules were detected using Fourier-transform infrared spectroscopy, while optical properties were studied using UV-visible spectroscopy. A uniform average particle size distribution in the range of 1–100 nm was confirmed by the particle size analyzer. Using cyclic voltammetry and galvanostatic charge/discharge measurements in a 6 M KOH solution, the electrochemical execution of NiMgOH-rGO nanocomposites was investigated. At a 1 A/g current density, the NiMgOH-rGO nanocomposites prepared with NH4OH as a reducing agent had a higher specific capacitance of 1977 F/g. The electrochemical studies confirmed that combining rGO with NiMgOH increased conductivity.

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Preparation of CuO/γ-Al2O3 Catalysts by Impregnationin Supercritical CO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.1313 ◽

2011 ◽

Vol 396-398 ◽

pp. 1313-1317

Author(s):

Li Min Li ◽

San Kui Xu ◽

Xiao Dong Wang ◽

Nan Nan Guo ◽

Yun Lai Su ◽

...

Keyword(s):

Catalytic Activity ◽

Xrd Analysis ◽

Catalyst Preparation ◽

Impregnation Method ◽

X Ray Diffraction ◽

X Ray ◽

Impregnation Time ◽

Temperature And Pressure ◽

Organometallic Precursors ◽

Adsorption Quantity

CuO/γ-Al2O3 catalysts were prepared by supercritical CO2 (SC-CO2) impregnation method. The preparation was carried out in SC-CO2 with Cu(NO3)2 as precursor, methanol as assistant solvent, and γ-Al2O3 as support. The effects of impregnation parameters such as temperature and pressure of SC-CO2, impregnation time, ratio of precursor to support, and amount of assistant solvent on catalyst preparation were investigated. The as-prepared catalysts were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis and compared to that prepared by the conventional impregnation method. The SC-CO2 impregnation method provided higher adsorption rate, larger adsorption quantity, more homogeneous dispersion of precursor, and stronger interaction between precursor and support. The catalytic degradation of methylene blue (MB) was used as probe reaction to estimate the catalytic activity of two catalysts prepared by two methods. The catalyst prepared by SC-CO2 impregnation method exhibits significantly improved catalytic activity. These results show that the inorganic metallic reagents as precursor with assistant solvent can be used as an alternative for the organometallic precursors in SC-CO2 impregnation method.

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The Effect of Cu Doping on the Transformation from Rutile to Anatase and Cu Occupation Tendency in TiO2 Solid Solution

Journal of Spectroscopy ◽

10.1155/2019/6470601 ◽

2019 ◽

Vol 2019 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

Jun-Yu Chen ◽

Ji-Kang Yan ◽

Guo-You Gan

Keyword(s):

Solid Solution ◽

Fourier Transform ◽

Sol Gel ◽

Calculated Data ◽

Xrd Analysis ◽

Vibration Frequencies ◽

X Ray Diffraction ◽

Cu Doping ◽

X Ray ◽

Stretching Vibration

TiO2 doped with different amounts of Cu2+ ions (from 0 to 3 mol%) was synthesized by sol-gel method. The samples were characterized by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The XRD analysis showed that the Cu-doped TiO2 samples exhibit anatase and rutile phases. The lattice parameters remain unchanged, independent of Cu2+ content. Diameter of TiO2 increased significantly with increasing concentrations of Cu2+. The investigated results indicate that a greater portion of the Cu2+ ions are well incorporated into the anatase and rutile TiO2 lattices. The stretching vibration frequencies of the interatomic bonds were calculated by the electronegativity principle. The calculated data were compared with infrared spectra. The results show that in the rutile and anatase phases, O atoms in the TiO2 lattice and some interstitial Cu atoms form Cu-O bond, and other substitutional Cu that replaces Ti atoms in TiO2 lattice form Cu-O bond with O atoms in the TiO2 lattice.

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VAlPOs as Efficient Catalysts for Glycerol Conversion to Methanol

Catalysts ◽

10.3390/catal10070728 ◽

2020 ◽

Vol 10 (7) ◽

pp. 728 ◽

Cited By ~ 1

Author(s):

Gheorghița Mitran ◽

Florentina Neațu ◽

Ștefan Neațu ◽

Mihaela M. Trandafir ◽

Mihaela Florea

Keyword(s):

Fourier Transform ◽

Catalytic Activity ◽

Sol Gel ◽

X Ray Diffraction ◽

Glycerol Molecule ◽

Glycerol Conversion ◽

X Ray ◽

Polymeric Species ◽

The One ◽

Vanadium Species

The catalytic activity of a series of vanadium aluminophosphates catalysts prepared by sol-gel method followed by combustion of the obtained gel was evaluated in glycerol conversion towards methanol. The materials were characterized by several techniques such as X-ray diffraction (XRD), UV-vis, Fourier-transform infrared (FTIR), Raman and X-ray photoelectron (XPS) spectroscopies. The amount of vanadium incorporated in aluminophosphates framework played an important role in the catalytic activity, while in the products distribution the key role is played by the vanadium oxidation state on the surface. The sample that contains a large amount of V4+ has the highest selectivity towards methanol. On the sample with the lowest vanadium loading the oxidation path to dihydroxyacetone is predominant. The catalyst with higher content of tetrahedral isolated vanadium species, such V5APO, is less active in breaking the C–C bonds in the glycerol molecule than the one containing polymeric species.

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Fourier Transform Infrared, UV-Visible, and X-Ray Diffraction Analyses of Organic Matter in Humin, Humic Acid, and Fulvic Acid Fractions in Soil Exposed to Elevated CO2 and N Fertilization

Applied Spectroscopy ◽

10.1366/0003702021954908 ◽

2002 ◽

Vol 56 (3) ◽

pp. 318-324 ◽

Cited By ~ 23

Author(s):

A. Naidja ◽

P. M. Huang ◽

D. W. Anderson ◽

C. Van Kessel

Keyword(s):

Organic Matter ◽

Fourier Transform ◽

Humic Acid ◽

Fulvic Acid ◽

Elevated Co2 ◽

Fourier Transform Infrared ◽

N Fertilization ◽

X Ray Diffraction ◽

X Ray ◽

Uv Visible

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Pyrolysis Synthesized g-C3N4for Photocatalytic Degradation of Methylene Blue

Journal of Chemistry ◽

10.1155/2013/187912 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 9

Author(s):

Gang Xin ◽

Yali Meng

Keyword(s):

Methylene Blue ◽

Fourier Transform ◽

Photocatalytic Activity ◽

Carbon Nitride ◽

Diffuse Reflectance ◽

Photogenerated Electron ◽

X Ray Diffraction ◽

X Ray ◽

Ft Ir ◽

Uv Visible

Graphitic carbon nitride (g-C3N4) was synthesized at 520°C by the pyrolysis of cyanamide, dicyandiamide, and melamine. The samples were characterized by X–ray diffraction (XRD), UV-visible diffuse reflectance spectra, Fourier transform infrared spectroscopy (FT-IR), and elemental analyzer. The photocatalytic activity of g-C3N4was evaluated by the photodegrading experiments of methylene blue (MB). The results indicated that g-C3N4. A photocatalytic mechanism presumed the MB photodegradation over the C3N4photocatalyst is attributed to photogenerated electron impelled multistep reduction of O2.

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Sintesis dan Karakterisasi TiO2 Terdoping Nitrogen (N-Doped TiO2) dengan Metode Sol–Gel

Jurnal Kimia Sains dan Aplikasi ◽

10.14710/jksa.19.2.63-67 ◽

2016 ◽

Vol 19 (2) ◽

pp. 63-67

Author(s):

Slamet Karim ◽

Pardoyo Pardoyo ◽

Agus Subagio

Keyword(s):

Fourier Transform ◽

Diffuse Reflectance ◽

Sol Gel ◽

Reflectance Spectra ◽

X Ray Diffraction ◽

Doped Tio2 ◽

X Ray ◽

Diffuse Reflectance Spectra ◽

Infra Red ◽

Uv Visible

Energi celah pita yang lebar dari semikonduktor TiO2 yang setara dengan cahaya ultraviolet (l<380 nm) membatasi aplikasi fotokatalitik hanya terbatas pada daerah ultraviolet dan tidak pada daerah cahaya tampak (l = 400 nm–700 nm). Pada penelitian ini dilakukan sintesis TiO2 teremban nitrogen yang dipreparasi melalui metode sol-gel. Prekursor TiCl4 digunakan sebagai sumber titanium dioksida dan CO(NH2)2 sebagai sumber nitrogen dan divariasi pada jumlah konsentrasi N dengan variasi 20 g, 30 g, 40 g dan 50 g. Refluks dilakukan pada suhu 100oC selama 7 jam dilanjutkan dengan pengeringan selama 3 jam pada suhu 100oC, dan kalsinasi pada suhu 500oC selama 7 jam . Karakterisasi N-doped TiO2 dilakukan menggunakan X-ray Diffraction (XRD), Fourier Transform–Infra Red spectroscopy (FTIR), dan UV- Visible diffuse reflectance spectra (UV-Vis DRS). Berdasarkan data XRD diketahui bahwa kristal N- doped TiO2 berstruktur anatase dengan indeks Miller 101. Spektra FTIR menunjukkan pergeseran serapan vibrasi O-Ti-O pada bilangan gelombang 400-1050 cm-1, diperkirakan sebagai akibat terbentuknya ikatan N-Ti-O. Spektrum DRS-UV–tampak menunjukkan penurunan energi celah pita dari TiO2 yakni 3,2 eV. Dapat disimpulkan bahwa penambahan konsentrasi nitrogen mengakibatkan penurunan energi celah pita, pada variasi 20g sebesar 3,12 eV, 30 g sebesar 3,09 eV, 40 g sebesar 3,082 eV, dan 50 g sebesar 3,08 eV.

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