Multiscale hybrid composites with carbon-based nanofillers

Author(s):  
Christian Matheus dos Santos Cougo ◽  
Sérgio Henrique Pezzin ◽  
Wagner Mauricio Pachekoski ◽  
Sandro Campos Amico
2016 ◽  
Vol 775 ◽  
pp. 235-242 ◽  
Author(s):  
Vinicius R. Gonçales ◽  
Rafael N.P. Colombo ◽  
Marco A.O.S. Minadeo ◽  
Elaine Y. Matsubara ◽  
J. Maurício Rosolen ◽  
...  

2015 ◽  
pp. 399-431
Author(s):  
S.T. Senthilkumar ◽  
K. Vijaya Sankar ◽  
J. S. Melo ◽  
A. Gedanken ◽  
R. Kalai Selvan

MRS Advances ◽  
2017 ◽  
Vol 2 (54) ◽  
pp. 3299-3307 ◽  
Author(s):  
Hoejin Kim ◽  
Mohammad Arif Ishtiaque Shuvo ◽  
Hasanul Karim ◽  
Juan C. Noveron ◽  
Tzu-liang Tseng ◽  
...  

ABSTRACTCarbon based materials have long been investigated as anodes for lithium ion batteries. Among these materials, porous carbon holds several advantages such as high stability, high specific surface area, and excellent cycling capability. To further enhance the energy storage performance, ceramic nanomaterials have been combined with carbon based materials as hybrid anodes for enhanced specific capacity. The use of metal oxide ceramic nanomaterials could enhance the surface electrochemical reactivity thus leads to the increasing of capacity retention at higher number of cycles. In this research, we synthesized ceria (CeO2) nano-particles on porous carbon to form inorganic-organic hybrid composites as an anode material for Li-ion battery. The high redox potential of ceria is expected to increase the specific capacity and energy density of the system. The electrochemical performance was determined by a battery analyzer. It is observed that the specific capacity could be improved by 77% using hybrid composites anode. The material morphology, crystal structure, and thermal stability were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), and Thermogravimetric Analysis (TGA).


Author(s):  
B. K. Kirchoff ◽  
L.F. Allard ◽  
W.C. Bigelow

In attempting to use the SEM to investigate the transition from the vegetative to the floral state in oat (Avena sativa L.) it was discovered that the procedures of fixation and critical point drying (CPD), and fresh tissue examination of the specimens gave unsatisfactory results. In most cases, by using these techniques, cells of the tissue were collapsed or otherwise visibly distorted. Figure 1 shows the results of fixation with 4.5% formaldehyde-gluteraldehyde followed by CPD. Almost all cellular detail has been obscured by the resulting shrinkage distortions. The larger cracks seen on the left of the picture may be due to dissection damage, rather than CPD. The results of observation of fresh tissue are seen in Fig. 2. Although there is a substantial improvement over CPD, some cell collapse still occurs.Due to these difficulties, it was decided to experiment with cold stage techniques. The specimens to be observed were dissected out and attached to the sample stub using a carbon based conductive paint in acetone.


2020 ◽  
Author(s):  
Idoia Hita ◽  
Tomas Cordero-Lanzac ◽  
Francisco J. Garcia-Mateos ◽  
Jose Rodriguez-Mirasol ◽  
Tomas Cordero ◽  
...  

2020 ◽  
Author(s):  
Idoia Hita ◽  
Tomas Cordero-Lanzac ◽  
Francisco J. Garcia-Mateos ◽  
Jose Rodriguez-Mirasol ◽  
Tomas Cordero ◽  
...  

2016 ◽  
Vol 2 (3) ◽  
pp. 47-57 ◽  
Author(s):  
S.S. Pesetskii ◽  
S.P. Bogdanovich ◽  
V.V. Dubrovskii ◽  
T.M. Sodyleva ◽  
V.N. Aderikha ◽  
...  

Author(s):  
H. Sh. Hammood ◽  
S. S. Irhayyim ◽  
A. Y. Awad ◽  
H. A. Abdulhadi

Multiwall Carbon nanotubes (MWCNTs) are frequently attractive due to their novel physical and chemical characteristics, as well as their larger aspect ratio and higher conductivity. Therefore, MWCNTs can allow tremendous possibilities for the improvement of the necessarily unique composite materials system. The present work deals with the fabrication of Cu-Fe/CNTs hybrid composites manufactured by powder metallurgy techniques. Copper powder with 10 vol. % of iron powder and different volume fractions of Multi-Wall Carbon Nanotubes (MWCNTs) were mixed to get hybrid composites. The hybrid composites were fabricated by adding 0.3, 0.6, 0.9, and 1.2 vol.% of MWCNTs to Cu- 10% Fe mixture using a mechanical mixer. The samples were compressed under a load of 700 MPa using a hydraulic press to compact the samples. Sintering was done at 900°C for 2 h at 5ºC/min heating rate. The microscopic structure was studied using a Scanning Electron Microscope (SEM). The effect of CNTs on the mechanical and wear properties, such as micro-hardness, dry sliding wear, density, and porosity were studied in detail. The wear tests were carried out at a fixed time of 20 minutes while the applied loads were varied (5, 10, 15, and 20 N). SEM images revealed that CNTs were uniformly distributed with relative agglomeration within the Cu/Fe matrix. The results showed that the hardness, density, and wear rates decreased while the percentage of porosity increased with increasing the CNT volume fraction. Furthermore, the wear rate for all the CNTs contents increased with the applied load.


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