scholarly journals Graphite/NiO/Ni Electrode for Electro-oxidation of the Remazol Black 5 Dye

2021 ◽  
Vol 16 (4) ◽  
pp. 847-856
Author(s):  
Ni Made Wiratini ◽  
Triyono Triyono ◽  
Wega Trisunaryanti ◽  
Agus Kuncaka

Graphite/NiO/Ni electrode had been fabricated for the electro-oxidation of remazol black 5 dye. The electrode was synthesized by electrodeposition method. Electro-oxidation of 100 ppm remazol black 5 dye was carried out at various concentrations of NaCl, 0.025; 0.05; 0.1; 0.25; and 0.5 M, variations in electro-oxidation time were 15, 30, 45, and 60 minutes, and pH variations were 4, 6, and 8. Cyclic voltammetry test revealed that graphite/NiO/Ni electrode had higher electrocatalytic capability compared to graphite electrode. The X-ray diffraction (XRD) patterns showed the decreasing value of 2θ from 44.6° for Ni to 43.5° for NiO. Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) showed that NiO/Ni deposited on the graphite surface in the form of solid grains and cracks, FTIR showed that δ(Ni−O) bond appeared at 582–511 cm−1. The decolorization efficiency of remazol black 5 for graphite/NiO/Ni electrode was 100% for 45 minutes of the electro-oxidation process, while the decolorization efficiency of remazol black 5 for graphite electrode was 99.74% for 60 minutes of the electro-oxidation process. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

2016 ◽  
Vol 23 (04) ◽  
pp. 1650027
Author(s):  
NORHANA MOHAMED RASHID ◽  
NAOKI KISHI ◽  
TETSUO SOGA

Pre-annealing as part of a two-step thermal oxidation process has a significant effect on the growth of hematite ([Formula: see text]-Fe2O3) nanowires on Fe foil. High-density aligned nanowires were obtained on iron foils pre-annealed at 300[Formula: see text]C under a dry air flow for 30[Formula: see text]min. The X-ray diffraction (XRD) patterns indicate that the nanowires are transformed from the small [Formula: see text]-Fe2O3 grains and uniquely grow in the (110) direction. The formation of a high-density of small grains by pre-annealing improved the alignment and density of the [Formula: see text]-Fe2O3 nanowires.


2020 ◽  
Vol 10 (03) ◽  
pp. 2050003
Author(s):  
M. R. Hassan ◽  
M. T. Islam ◽  
M. N. I. Khan

In this research, influence of adding Li2CO3 (at 0%, 2%, 4%, 6%) on electrical and magnetic properties of [Formula: see text][Formula: see text]Fe2O4 (with 60% Ni and 40% Mg) ferrite has been studied. The samples are prepared by solid state reaction method and sintered at 1300∘C for 6[Formula: see text]h. X-ray diffraction (XRD) patterns show the samples belong to single-phase cubic structure without any impurity phase. The magnetic properties (saturation magnetization and coercivity) of the samples have been investigated by VSM and found that the higher concentration of Li2CO3 reduces the hysteresis loss. DC resistivity increases with Li2CO3 contents whereas it decreases initially and then becomes constant at lower value with temperature which indicates that the studied samples are semiconductor. The dielectric dispersion occurs at a low-frequency regime and the loss peaks are formed in a higher frequency regime, which are due to the presence of resonance between applied frequency and hopping frequency of charge carriers. Notably, the loss peaks are shifted to the lower frequency with Li2CO3 additions.


Author(s):  
Peng Liu ◽  
Hongbin Zhang ◽  
Sinong Wang ◽  
Hui Yu ◽  
Bingjie Lu ◽  
...  

AbstractThe crystallinity indices (CrI) of Chinese handmade papers were investigated using the X-ray diffraction (XRD) method. Four Chinese handmade papers, Yingchun, Zhuma, Yuanshu and Longxucao papers were used as model substrates of mulberry bark, ramie, bamboo and Eulaliopsis binata papers, respectively. Two forms of the paper samples, paper sheets and their comminuted powders, were used in this study. The results showed that their XRD patterns belong to the cellulose-I type and Iβ dominates the cellulose microstructure of these paper samples. Moreover, it was found that the microstructures and CrIs of cellulose of these papers were changed by the grinding treatment. This work suggested that the sheet form of the handmade papers is suitable to determine CrI by XRD, despite the contribution of non-cellulosic components in the papers. The order of CrIs for these paper sheet samples was Yingchun, Zhuma, Longxucao and Yuanshu papers. Besides CrIs, differences in cross-sectional areas of the crystalline zone of cellulose can be used for comparing different types of handmade papers. It was also found that the CrIs and crystallite size of paper cellulose varied between the sheet samples and the powder samples, illustrating that the pulverisation has a negative influence on the microstructure of the handmade papers.


2011 ◽  
Vol 415-417 ◽  
pp. 1675-1678
Author(s):  
Kai Ning Yu ◽  
Cheng Wang ◽  
Yang Yu ◽  
Yan Li

The decolorization of coking wastewater is an urgent issue for coking wastewater treatment. Using mineral adsorbents to deal with the coking wastewater is an effective way to solve the above problem. In this paper, fluidized bed combustion (FBC) ashes, diatomite and clinoptiolite were used to decolorize the coking wastewater. UV-Vis was used to estimate the decolorization efficiency of the FBC ashes. The materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the sequence rule for the decolorization effect of three mineral adsorbents is FBC ashes > diatomite > clinoptiolite. In addition, the chroma of treated coking wastewater reduced from 320 times to less than 5 times in the comparison of raw wastewater. It is much lower than the chroma of GB8978-1996 1A discharge standard. The excellent decolorization effect of FBC ashes might be due to large contains of CaO and f-CaO.


2014 ◽  
Vol 1061-1062 ◽  
pp. 83-86
Author(s):  
Hong Wu ◽  
De Yi Zheng

In this paper, the effects of different sintering temperature on the microstructure and piezoelectric properties of Pb(Nb2/3Zn1/3)0.03(Zr52Ti48)0.97O3(PNZZT) ceramic samples were investigated. The Pb(Nb2/3Zn1/3)0.03(Zr52Ti48)0.97O3 ceramics materials was prepared by a conventional mixed oxide method. In the period of the experiment, the relationship between crystallographic phase and microstructure were analyzed by X-ray diffraction(XRD) and scanning electron microscopy(SEM) respectively. The XRD patterns shows that all of the ceramic samples are with a tetragonal perovskite structure. Along with sintering temperature increased and the x is 0.03, the grain size gradually become big. Through this experiment, it has been found that when the x is 0.03 and sintered at 1130°C for 2 h, the grains grow well, the grain-boundary intersection of the sample combined well and the porosity of the ceramics decreased, an excellent comprehensive electrical properties of the Pb(Nb2/3Zn1/3)0.03(Zr52Ti48)0.97O3 samples can be obtained. Its best electrical properties are as follows: dielectric constant (ε) is 1105, dielectric loss(tg) is 0.017, electromechanical coupling coefficient (Kp) is 0.287, piezoelectric constant(d33) is 150PC/N


1990 ◽  
Vol 208 ◽  
Author(s):  
Ichiro Hirosawa ◽  
Jun'ichiro Nizuki ◽  
Toru Tatsumi ◽  
Koichi Akimoto ◽  
Junji Matsui

ABSTRACTIn order to investigate the initial oxidation process Qf the Si (111) surface, we have studied the molecular beam deposited Si0 2/Si(111)-7×7 interface structure using grazing incidence X-ray diffraction geometry. We suggest a three-fold symmetry structural model composed of stacking fault layer, dimer layer and additional ordered atoms. The three-fold symmetry structure comes from the preference for oxidation in the faulted half of the 7×7 structure.


2021 ◽  
Author(s):  
Vikash Gajraj ◽  
Alesh Kumar ◽  
Ekta Dadarwal ◽  
Rahul Kaushik ◽  
Amilan Jose Devadoss ◽  
...  

Different weight percentages of NiCo2O4–rGO nanocomposites were prepared via a facile hydrothermal method. The prepared nanocomposites were structurally and morphologically characterized by X-ray diffraction, Raman spectroscopy and electron microscopies. The...


2009 ◽  
Vol 79-82 ◽  
pp. 71-74
Author(s):  
Qi Wang ◽  
Lin Qiao ◽  
Peng Song

In this paper, the resistance to H2S attack of pastes made from slag-fly ash blended cement used in oil well (SFAOW) was studied, in which fly ash (FA) was used at replacement dosages of 30% to 60% by weight of slag. Samples of SCOW and SFAOW pastes were demoulded and cured by immersion in fresh water with 2 Mp H2S insulfflation under 130oC for 15 days. After this curing period, compression strength and permeability of the samples were investigated. The reaction mechanisms of H2S with the paste were carried out through a microstructure study, which included the use of x-ray diffraction (XRD) patterns and scanning electron microscope (SEM). Based on the obtained data in this study, incorporation of FA into SCOW results in the comparable effects in the resistance to H2S attack. When the replacement dosage of slag is about 40%, the paste exhibits the best performance on resistance to H2S attack with compression strength 36.58Mp.


2013 ◽  
Vol 12 (01) ◽  
pp. 1350006
Author(s):  
AHMED E. HANNORA ◽  
FARIED F. HANNA ◽  
LOTFY K. MAREI

Mechanical alloying (MA) method has been used to produce nanocrystallite Mn -15at.% Al alloy. X-ray diffraction (XRD) patterns for the as-milled elemental α- Mn and aluminum powder samples show a mixture of α + β- MnAl phases after 20 h of milling and changes to a dominant β- MnAl phase structure after 50 h. An average crystallite size of 40 nm was determined from Hall–Williamson method analysis after 5 h of milling. Moreover, the thermal analysis results using differential thermal analysis (DTA), suggested a possible phase transformation after 20 h of milling. Isothermal treatments are carried in the temperature range of 450°C to 1000°C. Room-temperature vibrating sample magnetometer (VSM) measurements of the hysteretic response revealed that the saturation magnetization Bs and coercivity Hc for 10 h ball milled sample are ~ 2.1 emu/g and ~ 92 Oe, respectively.


2006 ◽  
Vol 11-12 ◽  
pp. 159-162 ◽  
Author(s):  
Yong Ge Cao ◽  
Lei Miao ◽  
Sakae Tanemura ◽  
Yasuhiko Hayashi ◽  
Masaki Tanemura

Transparent indium-doped ZnO (IZO) films with low In content (<6at%) were fabricated through radio-frequency (rf) helicon magnetron sputtering. Formation of In-Zn-O solid solution was confirmed by X-ray diffraction (XRD) patterns. Incorporation of indium into ZnO films enhances the optical transmission in the visible wavelength. The optical band-gaps slightly increase from 3.25eV (ZnO) to 3.28eV (In0.04Zn0.96O) and to 3.30eV (In0.06Zn0.94O) due to Burstain-Moss effect. The Urbach tail parameter E0, which is believed to be a function of structural disorder, increases from 79meV (ZnO), to 146meV (In0.04Zn0.96O), and to 173meV (In0.06Zn0.94O), which is consistent with increase of Full-Width Half-Maximum (FWHM) in corresponding XRD patterns. Decreasing in crystal quality with increasing indium concentration is also confirmed by photoluminescence spectra.


Sign in / Sign up

Export Citation Format

Share Document