scholarly journals Preparation and Electrochemical Properties of Functionalized Multi-Walled Carbon Nanotubes @ Carbon Quantum Dots @ Polyaniline Ternary Composite Electrode Materials

2020 ◽  
Vol 10 (16) ◽  
pp. 5462
Author(s):  
Jing Wang ◽  
Youyang Chen ◽  
Zhihao Hu ◽  
Ye Ge ◽  
Guotao Dong ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Quantum Dots ◽  
Electrochemical Properties ◽  
Specific Capacitance ◽  
Field Emission ◽  
Electrode Materials ◽  
Carbon Quantum Dots ◽  
Constant Current ◽  
Ternary Composite

Based on various carbon nano materials, the ternary composite functionalized carbon nanotubes (FMWCNTs) @ carbon quantum dots (CQDs) @ polyaniline (PANI) was prepared by in-situ polymerization and hydrothermal method. The carbon-based material was made into an electrode sheet. The morphology and microscopic nanostructures were characterized by FTIR, field emission scanning electron microscopy and field emission transmission electron microscopy. Cyclic voltammetry and the galvanostatic charge discharge method was adapted to study the electrochemical properties of these active materials. Our results showed that the specific capacitance of FMWCNTs @ CQDs @ PANI was as high as 534 F/g, while it was 362 F/g, 319 F/g and 279 F/g for PANI @ FMWCNTs, PANI @ CQDs and polyaniline. This means that the specific capacitance of FMWCNTs @ CQDs @ PANI is increased by 47.5%, 67.4% and 91.4% comparing with the capacitance of PANI @ FMWCNTs, PANI @ CQDs and polyaniline, respectively. Moreover, the specific capacitance retention rate of the ternary active electrode after 1000 times of constant current charge and discharge cycle reached 86%, while it was 60% for PANI @ FMWCNTs, 72% for PANI @ CQDs and 65% for polyaniline.

Carbon Quantum Dots/Polyaniline Nanocomposite (S-CQD/PANI) for High Capacitive Asymmetric Supercapacitor Device

2020 ◽  
Vol 20 (6) ◽  
pp. 3785-3794 ◽  
Author(s):  
Manohar D. Mehare ◽  
Abhay D. Deshmukh ◽  
S. J. Dhoble
Keyword(s):  
Quantum Dots ◽  
Specific Capacitance ◽  
Electrode Materials ◽  
Aqueous Electrolyte ◽  
Carbon Quantum Dots ◽  
Electrode System ◽  
Potential Range ◽  
Asymmetric Supercapacitor ◽  
Supercapacitor Application ◽  
Excellent Stability

A sucrose derived carbon quantum dots/polyaniline (S-CQD/PANI) nanocomposite was synthesized as electrode materials by electrodeposition method to achieve excellent electrocapacitive performance for supercapacitor application. The morphology reveals that CQD were distributed uniformly over the surface of PANI. The highest specific capacitance obtained to be 1512.4 Fg−1 at current density 1 Ag−1 for S-CQD/PANI-25 composite in three electrode system with 1 M H2SO4 aqueous electrolyte within the potential range of −0.2 to 0.8 V. In addition asymmetric supercapacitor device was fabricated reveals highest specific capacitance of 295 Fg−1 at 1 Ag−1 with excellent stability over 1000 cycle at 3 Ag−1. Remarkably, the device delivers energy density of 40.86 Whkg−1 at power density 2000 Wkg−1.

Electrochemical Detection of Bisphenol A Based on N-Doped Carbon Quantum Dots@Carbon Nanotubes Composite

2020 ◽  
Vol 20 (12) ◽  
pp. 7610-7617
Author(s):  
Zhongzhen Chen ◽  
Haiping Huang ◽  
Yanan Chen ◽  
Ying Ye ◽  
Shuzhen Wu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Quantum Dots ◽  
Bisphenol A ◽  
Differential Pulse Voltammetry ◽  
Electrochemical Detection ◽  
Glassy Carbon ◽  
Differential Pulse ◽  
Carbon Quantum Dots ◽  
Pulse Voltammetry

A novel nanocomposite of N-Doped Carbon Quantum Dots@Carbon Nanotubes was synthesized in this study for electrochemical detection of bisphenol A by differential pulse voltammetry. The nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, X-ray powder diffraction and Fourier transform infrared spectroscopy. Electrochemical properties of the nanocomposite modified glassy carbon electrodes were studied via cyclic voltammetry. Differential pulse voltammetry experimental results showed that N-Doped Carbon Quantum Dots@Carbon Nanotubes/glassy carbon electrode exhibited excellent catalysis activity towards electrochemical oxidation of bisphenol A. The oxidation peak current was linearly increased with concentration of bisphenol A in the range from 0.4 μM to 40 μM, with a limit of detection of 65 nM.

3D hierarchical porous N-doped carbon quantum dots/vanadium nitride hybrid microflowers as a superior electrode material toward high-performance asymmetric capacitive deionization

2021 ◽  
Author(s):  
Jingxuan Zhao ◽  
Zhibo Zhao ◽  
Yang Sun ◽  
Xiangdong Ma ◽  
Meidan Ye ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Electrode Material ◽  
High Performance ◽  
Carbon Nanomaterials ◽  
Electrode Materials ◽  
Carbon Quantum Dots ◽  
Vanadium Nitride ◽  
Capacitive Deionization ◽  
Hierarchical Porous

Taking into account of time-confusing preparation processing and unsatisfied desalination capacity of carbon nanomaterials, exploring efficient electrode materials remains a great challenge for practical capacitive deionization (CDI) application. In this...

Coral-Shaped TiO2−δ Decorated with Carbon Quantum Dots and Carbon Nanotubes for NO Removal

2021 ◽  
Author(s):  
Yucheng Ou ◽  
Gangqiang Zhu ◽  
Fei Rao ◽  
Jianzhi Gao ◽  
Jun Chang ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Quantum Dots ◽  
Carbon Quantum Dots ◽  
No Removal

Hybrid nanostructured C-dot decorated Fe3O4electrode materials for superior electrochemical energy storage performance

2015 ◽  
Vol 44 (19) ◽  
pp. 9221-9229 ◽  
Author(s):  
K. Bhattacharya ◽  
P. Deb
Keyword(s):  
Quantum Dots ◽  
Energy Storage ◽  
Specific Capacitance ◽  
High Specific Capacitance ◽  
Carbon Quantum Dots ◽  
Electrochemical Energy Storage ◽  
The Novel ◽  
Hybrid Nanocomposite ◽  
Storage Performance ◽  
Electrochemical Energy

Here, the novel Fe3O4-C hybrid nanocomposite demonstrates high specific capacitance (S.C.) than the pristine Fe3O4nanospheres due to the presence of the highly conducting carbon quantum dots.

scholarly journals Stable Copper Tin Sulfide Nanoflower Modified Carbon Quantum Dots for Improved Supercapacitors

2019 ◽  
Vol 2019 ◽  
pp. 1-5 ◽  
Author(s):  
Zhen Bi ◽  
Lanyan Huang ◽  
Chaoqun Shang ◽  
Xin Wang ◽  
Guofu Zhou
Keyword(s):  
Quantum Dots ◽  
Volume Change ◽  
Electrode Materials ◽  
Rate Capability ◽  
Carbon Quantum Dots ◽  
High Rate ◽  
Electrochemical Performances ◽  
Tin Sulfide ◽  
Transmission Electron ◽  
Tin Sulfides

Copper tin sulfides (CTSs) have widely been investigated as electrode materials for supercapacitors owing to their high theoretical pseudocapacitances. However, the poor intrinsic conductivity and volume change during redox reactions hindered their electrochemical performances and broad applications. In this study, carbon quantum dots (CQDs) were employed to modify CTSs. The structures and morphologies of obtained materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD revealed CTSs were composed of Cu2SnS3 and Cu4SnS4, and TEM suggested the decoration of CQDs on the surface of CTSs. With the decoration of CQDs, CTSs@CQDs showed a remarkable specific capacitance of 856 F·g−1 at 2 mV·s−1 and a high rate capability of 474 F·g−1 at 50 mV·s−1, which were superior to those of CTSs (851 F·g−1 at 2 mV·s−1 and 192 F·g−1 at 50 mV·s−1, respectively). This was mainly ascribed to incorporation of carbon quantum dots, which improved the electrical conductivity and alleviated volume change of CTSs during charge/discharge processes.

Study of Field Emission Behavior of Carbon Nanotubes with Different Sources

2002 ◽  
Vol 728 ◽  
Author(s):  
Mark Ching-Cheng Lin ◽  
M.S. Lai ◽  
H. J. Lai ◽  
M. H. Yang ◽  
B.Y. Wei ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Field Emission ◽  
Arc Discharge ◽  
Metal Catalyst ◽  
Microstructural Investigation ◽  
Emission Properties ◽  
Field Emission Properties ◽  
Different Sources

AbstractThe field emission properties of carbon nanotubes (CNTs) from various sources are investigated for the application of field emission displays. Comparisons are made between graphite with Ni metal as catalyst and polycyclic aromatic hydrocarbon as precursor by the arc discharge method. Cathode deposits are examined using scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) to determine microstructure. Carbon structure is studied using Raman spectroscopy. Electron field emission characteristics are measured with the diode method at 10-6 torr pressure. In this study, SEM micrographs of cathode deposits show dense random fiber-like carbon nanotubes. The HRTEM images clearly exhibit characteristic features of multiwalled carbon nanotubes. Microstructural investigation provides evidence that both the metal catalyst and the precursor can be used to synthesize carbon nanotubes. The Raman spectrum shows a stronger peak at about 1580 cm-1 indicating formation of a well-graphitized carbon nanotube. The degree of carbon nanotube graphitization is high and is in good agreement with the HRTEM result. From field emission measurements, the lowest onset field is about 1.0 V/μm and can be attributed to highly sharp tips and the high density of carbon nanotubes. Based on microstructure characterization and field emission measurements, the influence on field emission properties including turn on voltage and threshold voltage of carbon nanotubes synthesized from different sources is discussed.

Nanostructured oxides for energy storage applications in batteries and supercapacitors

2009 ◽  
Vol 81 (8) ◽  
pp. 1489-1498 ◽  
Author(s):  
Amreesh Chandra ◽  
Alexander J. Roberts ◽  
Eric Lam How Yee ◽  
Robert C. T. Slade
Keyword(s):  
Electron Microscopy ◽  
Energy Storage ◽  
Specific Capacitance ◽  
Electrode Materials ◽  
Particle Morphology ◽  
Hydrothermal Route ◽  
Conductivity Enhancement ◽  
Surface Areas ◽  
Transmission Electron

Nanostructured materials are extensively investigated for application in energy storage and power generation devices. This paper deals with the synthesis and characterization of nanomaterials based on oxides of vanadium and with their application as electrode materials for energy storage systems viz. supercapacitors. These nano-oxides have been synthesized using a hydrothermal route in the presence of templates: 1-hexadecylamine, Tweens and Brij types. Using templates during synthesis enables tailoring of the particle morphology and physical characteristics of synthesized powders. Broad X-ray diffraction peaks show the formation of nanoparticles, confirmed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations. SEM studies show that a large range of nanostructures such as needles, fibers, particles, etc. can be synthesized. These particles have varying surface areas and electrical conductivity. Enhancement of surface area as much as seven times relative to surface areas of starting parent materials has been observed. These properties make such materials ideal candidates for application as electrode materials in supercapacitors. Assembly and characterization of supercapacitors based on electrodes containing these active nano-oxides are discussed. Specific capacitance of >100 F g–1 has been observed. The specific capacitance decreases with cycling: causes of this phenomenon are presented.

A Facile Synthesis of NiFe2O4 with High Specific Capacitance as Supercapacitor Electrode Material

2018 ◽  
Vol 281 ◽  
pp. 854-858
Author(s):  
Xi Cheng Gao ◽  
Jian Qiang Bi ◽  
Wei Li Wang ◽  
Guo Xun Sun ◽  
Xu Xia Hao ◽  
...  
Keyword(s):  
Particle Size ◽  
Specific Capacitance ◽  
Electrochemical Property ◽  
Electrode Materials ◽  
High Specific Capacitance ◽  
Constant Current ◽  
X Ray Diffraction ◽  
Supercapacitor Electrode ◽  
Constant Current Charge ◽  
Supercapacitor Electrode Materials

NiFe2O4 powders were synthesized by a facile hydrothermal method at 180°C followed by a thermal treatment at 300°C. The phase composition and morphology were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results showed that the NiFe2O4 powders were well-crystallized, and they possessed a particle size in the range of 50-100 nm. The electrochemical property was characterized via cyclic voltammetry (CV) and constant current charge-discharge method. Encouragingly, the NiFe2O4 powders had an excellent electrochemical property, whose specific capacitance reached 266.84 F/g at the electric current density of 1 A/g due to the small particle size. Compared with other Fe-based metal compound oxides, NiFe2O4 has a better electrochemical performance, which can be widely used in the supercapacitor electrode materials.

Sign in / Sign up

Export Citation Format

Share Document