scholarly journals Nitrogen, Phosphorus and Sulfur Co-Doped Pyrolyzed Bacterial Cellulose Nanofibers for Supercapacitors

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1912
Author(s):  
Zheng Li ◽  
Yaogang Wang ◽  
Wen Xia ◽  
Jixian Gong ◽  
Shiru Jia ◽  
...  
Keyword(s):  
Bacterial Cellulose ◽  
High Performance ◽  
Electrode Materials ◽  
Cellulose Nanofibers ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Nitrogen Phosphorus ◽  
Co Doped

Heteroatom doping is an effective way to raise the electrochemical properties of carbon materials. In this paper, a novel electrode material including nitrogen, phosphorus, and sulfur co-doped pyrolyzed bacterial cellulose (N/P/S-PBC) nanofibers was produced. The morphologies, structure characteristics and electrochemical performances of the materials were investigated by Scanning electron microscopy, Fourier transform infrared spectra, X-ray diffraction patterns, X-ray photoelectronic spectroscopy, N2 sorption analysis and electrochemical measurements. When 3.9 atom% of nitrogen, 1.22 atom% of phosphorus and 0.6 atom% of sulfur co-doped into PBC, the specific capacitance of N/P/S-PBC at 1.0 A/g was 255 F/g and the N/P/S-PBC supercapacitors’ energy density at 1 A/g was 8.48 Wh/kg with a power density of 489.45 W/kg, which were better than those of the N/P-PBC and N/S-PBC supercapacitors. This material may be a very good candidate as the promising electrode materials for high-performance supercapacitors.

A Quantitative Picture of the Fringed Micellar Model of Cellulose

1971 ◽  
Vol 41 (8) ◽  
pp. 647-653 ◽  
Author(s):  
A. M. Scallan
Keyword(s):  
Acid Hydrolysis ◽  
Bacterial Cellulose ◽  
Deuterium Oxide ◽  
Tire Cord ◽  
X Ray Diffraction ◽  
Wood Cellulose ◽  
X Ray ◽  
Diffraction Patterns ◽  
Recent Interpretation

Quantitative diagrams of the fringed micellar model have been produced for tire cord, Fortisan, wood cellulose, cotton, ramie and bacterial cellulose, based on the results of the reactivities of these celluloses towards deuterium oxide and acid hydrolysis. The hypothesis has been used that rapid acid hydrolysis occurs in the truly amorphous zones, whereas deuteration occurs not only in these zones but also on the surfaces of the crystallites. It is from this hypothesis that calculations of crystallinity, crystallite width, and crystallite length have been made. The calculated fractional crystallinities of native celluloses are, therefore, in the range of 0.89-0.96, while those of regenerated celluloses range from 0.65 to 0.85. These crystallinities are higher than previously accepted values and are more in keeping with the most recent interpretation of x-ray diffraction patterns. The values of calculated crystallite width were about 17Å for the regenerated celluloses and 32Å for native celluloses. The latter value is close to that currently proposed by electron microscopists. Crystallite lengths were calculated from the levelling-off DP found on acid hydrolysis. The various methods of measuring crystallinity are discussed in terms of the model, as are microfibrils, crystallites, and paracrystalline cellulose.

scholarly journals Zn/F-doped tin oxide nanoparticles synthesized by laser pyrolysis: structural and optical properties

2019 ◽  
Vol 10 ◽  
pp. 9-21 ◽  
Author(s):  
Florian Dumitrache ◽  
Iuliana P Morjan ◽  
Elena Dutu ◽  
Ion Morjan ◽  
Claudiu Teodor Fleaca ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Laser Energy ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Laser Pyrolysis ◽  
One Step ◽  
Diffraction Patterns ◽  
Tin Oxide Nanoparticles ◽  
Co Doped

Zn/F co-doped SnO2 nanoparticles with a mean diameter of less than 15 nm and a narrow size distribution were synthesized by a one-step laser pyrolysis technique using a reactive mixture containing tetramethyltin (SnMe4) and diethylzinc (ZnEt2) vapors, diluted Ar, O2 and SF6. Their structural, morphological, optical and electrical properties are reported in this work. The X-ray diffraction (XRD) analysis shows that the nanoparticles possess a tetragonal SnO2 crystalline structure. The main diffraction patterns of stannous fluoride (SnF2) were also identified and a reduction in intensity with increasing Zn percentage was evidenced. For the elemental composition estimation, energy dispersion X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) measurements were performed. In general, both analyses showed that the Zn percentage increases with increasing ZnEt2 flow, accompanied at the same time by a decrease in the amount of F in the nanopowders when the same SF6 flow was employed. The Raman spectra of the nanoparticles show the influence of both Zn and F content and crystallite size. The fluorine presence is due to the catalytic partial decomposition of the SF6 laser energy transfer agent. In direct correlation with the increase in the Zn doping level, the bandgap of co-doped nanoparticles shifts to lower energy (from 3.55 to 2.88 eV for the highest Zn dopant concentration).

scholarly journals Synthesis of Platinum Nanoparticles from K2PtCl4 Solution Using Bacterial Cellulose Matrix

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
H. F. Aritonang ◽  
D. Onggo ◽  
C. Ciptati ◽  
C. L. Radiman
Keyword(s):  
Bacterial Cellulose ◽  
Pt Nanoparticles ◽  
Precursor Solution ◽  
Hydrogen Gas ◽  
Precursor Concentration ◽  
X Ray Diffraction ◽  
X Ray ◽  
Potassium Tetrachloroplatinate ◽  
Diffraction Patterns ◽  
Tga Analysis

Platinum (Pt) nanoparticles have been synthesized from a precursor solution of potassium tetrachloroplatinate (K2PtCl4) using a matrix of bacterial cellulose (BC). The formation of Pt nanoparticles occurs at the surface and the inside of the BC membrane by reducing the precursor solution with a hydrogen gas reductant. The Pt nanoparticles obtained from the variations of precursor concentration, between 3 mM and 30 mM, and the formation of Pt nanoparticles have been studied using X-ray diffraction (XRD), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), and thermogravimetry analysis (TGA). Based on X-ray diffraction patterns, Pt particles have sizes between 6.3 nm and 9.3 nm, and the Pt particle size increases with an increase in precursor concentration. The morphology of the Pt nanoparticles was observed by SEM-EDS and the content of Pt particles inside the membrane is higher than that on the surface of BC membranes. This analysis corresponds to the TGA analysis, but the TGA analysis is more representative in how it describes the content of Pt particles in the BC membrane.

Capacitive Study of Ni(OH)2 Xerogels in KOH Solution

2012 ◽  
Vol 608-609 ◽  
pp. 1106-1110
Author(s):  
Xin Jin Tian ◽  
Jie Cheng ◽  
Yue Hua Wen ◽  
Gao Ping Cao ◽  
Han Min Liu
Keyword(s):  
Cyclic Voltammetry ◽  
High Performance ◽  
Electrode Materials ◽  
Ambient Pressure ◽  
Sol Gel ◽  
Constant Current ◽  
Electrochemical Activation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Average Size

Ni(OH)2 xerogels were formed by sol-gel method at 80 °C followed drying at 110 °C and ambient pressure. The structure of Ni(OH)2 xerogels was characterized using X-ray diffraction, transmission electron microscope (TEM) and N2 (77K) adsorption. X-Ray Diffraction (XRD) results showed that the material obtained has a crystalline -Ni(OH)2. TEM images showed that average size of the crystalline phase is about 10 nm. Results of N2 (77K) adsorption isotherm showed that the (BET) specific surface area is 232 m2/g and the Pore size distribution is in the regime 1-4 nm (Barrett–Joyner–Halenda, BJH). The Ni(OH)2 xerogels electrodes were activated using cyclic voltammetry, and their capacitive performance was evaluated using cyclic voltammetry (CV) and constant current discharge. The Ni(OH)2 xerogels electrodes exhibited excellent capacitive behavior with a specific capacitance of 635 F/g (calculated by CV). High performance obtained indicates that the Ni(OH)2 xerogels are promising electrode materials for supercapacitors, and the electrochemical activation of these electrodes is doable.

Optical Absorption of Er3+/Nd3+ Co-Doped Tellurite Glass

2012 ◽  
Vol 501 ◽  
pp. 96-100 ◽  
Author(s):  
S. Akmar Roslan ◽  
M. Rahim Sahar ◽  
Ramli Arifin ◽  
Sib Krishna Ghoshal ◽  
M. Supar Rohani ◽  
...  
Keyword(s):  
Tellurite Glass ◽  
Optical Band Gap ◽  
Urbach Energy ◽  
Tellurite Glasses ◽  
X Ray Diffraction ◽  
Melt Quenching ◽  
X Ray ◽  
Diffraction Patterns ◽  
Quenching Method ◽  
Co Doped

Tellurite glasses of varying Er3+/Nd3+ concentration were successfully prepared by melt-quenching method. The X-Ray diffraction pattern was determined by using Siemens Diffractometer D5000 while the optical properties were measured using Shimadzu 3101 pc UV-VIS NIR scanning spectrophotometer. It was found that the diffraction patterns of all samples showed glasses characteristics. The optical band gap, Eopt¬ increased proportionally with the content of Er¬2O3 but Urbach energy, ∆E decreased due to the increasing Er2O3 contents.

The Capacitive Behavior of Ni0.76Co0.24Ox Xerogels in KOH Solution

2012 ◽  
Vol 608-609 ◽  
pp. 1092-1096
Author(s):  
Jie Cheng ◽  
Xin Jin Tian ◽  
Yue Hua Wen ◽  
Yan Xu ◽  
Han Min Liu ◽  
...  
Keyword(s):  
High Performance ◽  
Electrode Materials ◽  
Sol Gel ◽  
Constant Current ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Capacitive Behavior ◽  
Heat Treated ◽  
A Current

Ni0.76Co0.24Ox xerogels were formed by the sol-gel method followed by heat-treatment in air. The structure and properties of these materials were characterized by using X-ray diffraction, TEM and N2 (77K) adsorption. Electrodes with the xerogels were activated by cyclic voltammetry (CV) and their capacitive performance was evaluated by galvanostatic technique in 7 mol/L KOH solutions. A maximum specific capacitance of 904 F/g was obtained by constant current discharge with a current density of 2.0 mA/cm2 for the Ni0.76Co0.24Ox xerogels heat-treated at 250°C. High performance obtained indicates that these materials are promising electrode materials for supercapacitors.

Solid-State Microwave Synthesis CuO/CNT: A High-Performance Electrode Material for Supercapacitors

NANO ◽  
2020 ◽  
Vol 15 (08) ◽  
pp. 2050102
Author(s):  
Xiaoqi Tan ◽  
Xiaolei Yue ◽  
Meng Yuan ◽  
Shuxia Liu ◽  
Yaodong Zhang ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
High Performance ◽  
Aqueous Electrolyte ◽  
Electrochemical Stability ◽  
Electrochemical Performances ◽  
Asymmetric Supercapacitor ◽  
X Ray Diffraction ◽  
Energy Storage Devices ◽  
X Ray ◽  
Storage Devices

CuO/CNT composites were synthesized via simple and rapid microwave approach. The nanocomposites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Further, the electrochemical performances of CuO/CNT composites were evaluated. The prepared samples displayed high specific capacitances of 164.5[Formula: see text]F[Formula: see text]g[Formula: see text] at 1[Formula: see text]A[Formula: see text]g[Formula: see text], during the cycle process, the capacitance value aggrandized to 274.7[Formula: see text]F[Formula: see text]g[Formula: see text], and the capacitance remained at 166% of the primary value after 10 000 turns. Moreover, the CuO/CNT//AC asymmetric supercapacitor (ASC) exhibited an energy density of 17.08[Formula: see text]Wh[Formula: see text]kg[Formula: see text] at 775[Formula: see text]W[Formula: see text]kg[Formula: see text] and excellent electrochemical stability in 6M KOH aqueous electrolyte, showing its enormous potential in energy-storage devices.

Preparation of oriented bacterial cellulose nanofibers by flowing medium-assisted biosynthesis and influence of flowing velocity

2018 ◽  
Vol 38 (3) ◽  
pp. 299-305 ◽  
Author(s):  
Honglin Luo ◽  
Wei Li ◽  
Zhiwei Yang ◽  
Haiyong Ao ◽  
Guangyao Xiong ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Bacterial Cellulose ◽  
Culture Medium ◽  
Cellulose Nanofibers ◽  
X Ray Diffraction ◽  
Tissue Engineering Scaffolds ◽  
X Ray ◽  
Biomimetic Scaffolds ◽  
Nanofiber Alignment ◽  
Thermal Stability Of

AbstractNanofiber alignment in tissue engineering scaffolds is a crucial factor controlling the cell behavior. In this work, we report a facile approach to obtain aligned nanofibers of bacterial cellulose (BC) by forcing the culture medium of bacteria to flow along a fixed direction. The emphasis of this work was placed on the effect of flowing velocity on the alignment of the as-prepared oriented BC (OBC). X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analyses indicated that the velocity affected the crystallinity and thermal stability of BC while the chemical structure did not change with the velocity. The controllable alignment of BC nanofibers makes them a promising material for the construction of biomimetic scaffolds for tissue engineering and regenerative medicine.

Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

1977 ◽  
Vol 35 ◽  
pp. 330-333
Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello
Keyword(s):  
Biological Materials ◽  
Molecular Organization ◽  
X Ray Diffraction ◽  
Glass Capillary ◽  
X Ray ◽  
Rate Dependent ◽  
Before And After ◽  
Freeze Etching ◽  
Diffraction Patterns ◽  
Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

Examination of Rabbit Fc Crystals

1968 ◽  
Vol 26 ◽  
pp. 140-141
Author(s):  
J. P. Robinson ◽  
P. G. Lenhert
Keyword(s):  
Molecular Weight ◽  
Flat Plate ◽  
Phosphate Buffer ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Neutral Ph ◽  
Small Crystals ◽  
Carbon Coated ◽  
Diffraction Patterns

Crystallographic studies of rabbit Fc using X-ray diffraction patterns were recently reported. The unit cell constants were reported to be a = 69. 2 A°, b = 73. 1 A°, c = 60. 6 A°, B = 104° 30', space group P21, monoclinic, volume of asymmetric unit V = 148, 000 A°3. The molecular weight of the fragment was determined to be 55, 000 ± 2000 which is in agreement with earlier determinations by other methods.Fc crystals were formed in water or dilute phosphate buffer at neutral pH. The resulting crystal was a flat plate as previously described. Preparations of small crystals were negatively stained by mixing the suspension with equal volumes of 2% silicotungstate at neutral pH. A drop of the mixture was placed on a carbon coated grid and allowed to stand for a few minutes. The excess liquid was removed and the grid was immediately put in the microscope.

Sign in / Sign up

Export Citation Format

Share Document