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 ◽  
...  

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.

2018 ◽  
Vol 27 (1) ◽  
pp. 3-10
Author(s):  
Chengyang Peng ◽  
Fosong Liu ◽  
Chunnian Chen

Graphene/nano-sulphur (S)/polyaniline (PANI) ternary nanocomposite was successfully synthesised and used as an electrode material for supercapacitors. In this process, the aniline was selected to accomplish two functions: In the first place, it served as a reducing agent, promoting the reduction of graphene oxide to graphene, without any additional reducing agent. In the second place, it played an important role in the formation of PANI. S nanoparticles were uniformly decorated on the graphene surface, and PANI covered the graphene/S surface. Furthermore, graphene and PANI prevented polysulphide species diffusion. The products were characterised by field-emission scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectra, X-ray photoelectron spectroscopy, Raman spectroscopy and electrochemical analysis. Owing to the specific combination of the advantages of graphene, nano-S and PANI, the composite exhibited outstanding electrochemical performance showing a specific capacitance as high as 619 F g−1 at a scan rate of 5 mV s−1 and excellent electrochemical stability with a retention of 77.9% (457 F g−1) of initial capacitance (586.8 F g−1) after 500 cycles at a current density of 1 A g−1.


Author(s):  
Anil Kumar Yedluri ◽  
Hee-Je Kim

CoO-ZnO-based composites have attracted considerable attention for the development of energy storage devices because of their multifunctional characterization and ease of integration with existing components. This paper reports the synthesis of CoO@ZnO (CZ) nanostructures on Ni foam by the CBD method for facile and eco-friendly supercapacitor applications. The formation of a CoO@ZnO electrode functioned with cobalt, zinc, nickel and oxygen groups was confirmed by X-ray diffraction, X-ray photoelectron spectroscopy, low and high-resolution of scanning electron microscopy, and transmission electron microscopy. The as-synthesized hierarchical nanocorn skeleton-like structure of CoO@ZnO-3h (CZ3h) electrode delivered a higher specific capacitance of 1136 F/g at a current density of 3 A/g with outstanding cycling stability, showing 98.3% capacitance retention over 3000 cycles in an aqueous 2 M KOH electrolyte solution. This retention was significantly better than that of other prepared electrodes, such as CoO (CO), ZnO (ZO), CoO@ZnO-1h (CZ1h), and CoO@ZnO-7h (CZ7h) (274, 383, 240 and 537 F/g, respectively). This superior capacitance was attributed to the ideal surface morphology of CZ3h, which is responsible for the rapid electron/ion transfer between the electrolyte and electrode surface area. The enhanced features of the CZ3h electrode highlight potential applications in high performance supercapacitors, solar cells, photocatalysis, and electrocatalysis.


Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 200 ◽  
Author(s):  
Ravi Bolagam ◽  
Sukkee Um

In this paper, we report the successful synthesis of cobalt ruthenium sulfides by a facile hydrothermal method. The structural aspects of the as-prepared cobalt ruthenium sulfides were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. All the prepared materials exhibited nanocrystal morphology. The electrochemical performance of the ternary metal sulfides was investigated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy techniques. Noticeably, the optimized ternary metal sulfide electrode exhibited good specific capacitances of 95 F g−1 at 5 mV s−1 and 75 F g−1 at 1 A g−1, excellent rate capability (48 F g−1 at 5 A g−1), and superior cycling stability (81% capacitance retention after 1000 cycles). Moreover, this electrode demonstrated energy densities of 10.5 and 6.7 Wh kg−1 at power densities of 600 and 3001.5 W kg−1, respectively. These attractive properties endow proposed electrodes with significant potential for high-performance energy storage devices.


Polymers ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 270
Author(s):  
Syed Shaheen Shah ◽  
Himadri Tanaya Das ◽  
Hasi Rani Barai ◽  
Md. Abdul Aziz

Energy generation can be clean and sustainable if it is dependent on renewable resources and it can be prominently utilized if stored efficiently. Recently, biomass-derived carbon and polymers have been focused on developing less hazardous eco-friendly electrodes for energy storage devices. We have focused on boosting the supercapacitor’s energy storage ability by engineering efficient electrodes in this context. The well-known conductive polymer, polyaniline (PANI), deposited on nickel foam (NF) is used as a positive electrode, while the activated carbon derived from jute sticks (JAC) deposited on NF is used as a negative electrode. The asymmetric supercapacitor (ASC) is fabricated for the electrochemical studies and found that the device has exhibited an energy density of 24 µWh/cm2 at a power density of 3571 µW/cm2. Furthermore, the ASC PANI/NF//KOH//JAC/NF has exhibited good stability with ~86% capacitance retention even after 1000 cycles. Thus, the enhanced electrochemical performances of ASC are congregated by depositing PANI on NF that boosts the electrode’s conductivity. Such deposition patterns are assured by faster ions diffusion, higher surface area, and ample electroactive sites for better electrolyte interaction. Besides advancing technology, such work also encourages sustainability.


2020 ◽  
Vol 851 ◽  
pp. 25-31
Author(s):  
Markus Diantoro ◽  
Ahmad Al Ittikhad ◽  
Thathit Suprayogi ◽  
Nasikhudin ◽  
Joko Utomo

The development of energy storage devices encourages the sustainability of research on basic materials of supercapacitor technology. SrTiO3 is one of metal oxide called as titanate alkali metal ATiO3 (A = Ba, Sr, Ca). This material shows an excellent dielectric constant, thus expected to be potential as raw material of supercapacitor. In this work, boron was used as a dopant on the SrTiO3 system to modify its local structure and enhance the electrical properties. Synthesis SrTi1-xBxO3 was carried out using a solid-state reaction method followed by the sintering process in various molar ratio. The microstructure of SrTi1-xBxO3 compound was identified by X-ray Diffraction with Cu-Kα. XRD pattern identified the presence of SrTi1-xBxO3 phase with a slight change in the lattice parameters. I-V measurement confirmed that the electrical conductivity increased gradually up to 16.04 Ω-1cm-1. For investigating their application for electrode materials, CV was employed and it presents that the specific capacitance and energy density of x = 0.08 were 5.488 Fg-1 and 0.110 Jg-1.


2019 ◽  
Vol 9 (4) ◽  
pp. 793 ◽  
Author(s):  
Camila Zequine ◽  
Fangzhou Wang ◽  
Xianglin Li ◽  
Deepa Guragain ◽  
S.R. Mishra ◽  
...  

The urea oxidation reaction (UOR) is a possible solution to solve the world’s energy crisis. Fuel cells have been used in the UOR to generate hydrogen with a lower potential compared to water splitting, decreasing the costs of energy production. Urea is abundantly present in agricultural waste and in industrial and human wastewater. Besides generating hydrogen, this reaction provides a pathway to eliminate urea, which is a hazard in the environment and to people’s health. In this study, nanosheets of CuCo2O4 grown on nickel foam were synthesized as an electrocatalyst for urea oxidation to generate hydrogen as a green fuel. The synthesized electrocatalyst was characterized using X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The electroactivity of CuCo2O4 towards the oxidation of urea in alkaline solution was evaluated using electrochemical measurements. Nanosheets of CuCo2O4 grown on nickel foam required the potential of 1.36 V in 1 M KOH with 0.33 M urea to deliver a current density of 10 mA/cm2. The CuCo2O4 electrode was electrochemically stable for over 15 h of continuous measurements. The high catalytic activities for the hydrogen evolution reaction make the CuCo2O4 electrode a bifunctional catalyst and a promising electroactive material for hydrogen production. The two-electrode electrolyzer demanded a potential of 1.45 V, which was 260 mV less than that for the urea-free counterpart. Our study suggests that the CuCo2O4 electrode can be a promising material as an efficient UOR catalyst for fuel cells to generate hydrogen at a low cost.


Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1912
Author(s):  
Zheng Li ◽  
Yaogang Wang ◽  
Wen Xia ◽  
Jixian Gong ◽  
Shiru Jia ◽  
...  

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.


Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6008
Author(s):  
Tahira Yaqoob ◽  
Malika Rani ◽  
Arshad Mahmood ◽  
Rubia Shafique ◽  
Safia Khan ◽  
...  

MXene/Ag2CrO4 nanocomposite was synthesized effectively by means of superficial low-cost co-precipitation technique in order to inspect its capacitive storage potential for supercapacitors. MXene was etched from MAX powder and Ag2CrO4 spinel was synthesized by an easy sol-gel scheme. X-Ray diffraction (XRD) revealed an addition in inter-planar spacing from 4.7 Å to 6.2 Å while Ag2CrO4 nanoparticles diffused in form of clusters over MXene layers that had been explored by scanning electron microscopy (SEM). Energy dispersive X-Ray (EDX) demonstrated the elemental analysis. Raman spectroscopy opens the gap between bonding structure of as-synthesized nanocomposite. From photoluminence (PL) spectra the energy band gap value 3.86 eV was estimated. Electrode properties were characterized by applying electrochemical observations such as cyclic voltammetry along with electrochemical impedance spectroscopy (EIS) for understanding redox mechanism and electron transfer rate constant Kapp. Additionally, this novel work will be an assessment to analyze the capacitive behavior of electrode in different electrolytes such as in acidic of 0.1 M H2SO4 has specific capacitance Csp = 525 F/g at 10 mVs−1 and much low value in basic of 1 M KOH electrolyte. This paper reflects the novel synthesis and applications of MXene/Ag2CrO4 nanocomposite electrode fabrication in energy storage devices such as supercapacitors.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mutaz Salih ◽  
M. Khairy ◽  
Babiker Abdulkhair ◽  
M. G. Ghoniem ◽  
Nagwa Ibrahim ◽  
...  

Abstract In this paper, Sn-doped TiO2 nanomaterials with varying concentrations were manufactured through a simple procedure. The fabricated TiO2 and Sn loaded on TiO2 nanoparticles were studied using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-rays, Fourier transform infrared spectroscopy, and resistance analyses. The benefits of dielectric constant and ac conductivity rise at high Sn loaded concentration on TiO2 nanoparticles. The enhanced electrical conductivity is seen for STO3 (3.5% Sn doped TiO2) and STO4 (5% Sn doped TiO2) specimens are apparently associated with the introduced high defect TiO2 lattice. Furthermore, the fabricated specimens’ obtained findings may be applied as possible candidates for high-energy storage devices. Moreover, proper for the manufacture of materials working at a higher frequency.


2008 ◽  
Vol 80 (11) ◽  
pp. 2327-2343 ◽  
Author(s):  
V. Subramanian ◽  
Hongwei Zhu ◽  
Bingqing Wei

Manganese oxides have been synthesized by a variety of techniques in different nanostructures and studied for their properties as electrode materials in two different storage applications, supercapacitors (SCs) and Li-ion batteries. The composites involving carbon nanotubes (CNTs) and manganese oxides were also prepared by a simple room-temperature method and evaluated as electrode materials in the above applications. The synthesis of nanostructured manganese oxides was carried out by simple soft chemical methods without any structure directing agents or surfactants. The prepared materials were well characterized using different analytical techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), surface area studies, etc. The electrochemical properties of the nanostructured manganese oxides and their composites were studied using cyclic voltammetry (CV), galvanostatic charge-discharge, and electrochemical impedance spectroscopic (EIS) studies. The influence of structural/surface properties on the electrochemical performance of the synthesized manganese oxides is reviewed.


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