الفهرس 
Necessity for Energy Storage
ExperimentalOnly 14 pages are availabe for public view
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Abstract
The study aims at the preparation and characterization of
nanostructured carbon-based materials for supercapacitors.
These materials impely the synthesis of electrodes that are
incorporateed with siver and some of the transition metals
oxides such as (Titanium oxide). Chemical and / or
electrochemical methods of synthesis were explored.
The main objectives of this study were concerned with:-
• Development of supercapacitor electrodes with long
lifetime.
• Acheiving high energy and power densities.
The content of the thesis can be summarized as:
I) The introduction includes a short outline of the
importce of The energy in our life and its applications
in devices, such as cell phones, pagers, stand-by
power systems, and electric/hybrid vehicles. Previous
studies on the graphene and its use in supercapacitors
related to the present investigation are reviewed and
discussed.
II) The experimental part includes the materials, reagents
used and the methods of preparation. The techniques
and apparatus are also outlined, as well as, the
experimental conditions associated with processes.III) The results obtained are explained and interpreted. In
chapter 3.
The main achievements and views discussed can be
presented as follows:
1) characterization of spongy graphene oxide (SGO),
reduced graphene oxide (RGO), functionalize of
grapheme oxide (FGO) and Functionalized graphene
(FG): characterization of functionalized graphene by
FESEM, TEM, XRD, UV, FT-IR, TGA, and Ramen
spectroscopy. Study of electrochemical behavior using
cyclic voltammetry and chornopotentiometry.
2) characterization of functionalized graphene (FG-Ag):
Characterization of functionalize graphene decorated
with Ag NPs FG-Ag by FESEM, TEM, XRD, UV, FT-IR,
TGA, EDX and Ramen spectroscopy. Study of the
electrochemical behavior using cyclic voltammetry and
chornopotentiometry. The composition of graphene and
silver nanoparticles containing 100:15 ratio in the composite
was found to have maximum synergistic effect resulting in
the highest capacitive property than the other ratios.3) characterization of Functionalized graphene (FGTiO2H)
Characterization of functionalized graphene by
FESEM, TEM, XRD, FT-IR, EDX and Ramen spectroscopy.
Study of the electtochemical behavior using cyclic
voltammetry and chornopotentiometry. The composition of
graphene and hydrogenated Titanium nano tubes containing
100:20 ratio in the composite was found to have maximum
synergistic effect resulting in the highest capacitive property
than the other ratio.
4) characterization of Functionalized N/P co-doped
graphene.
Characterization of N/P co-doped graphene by
FESEM, TEM, XRD, UV, FT-IR, TGA, and Ramen
spectroscopy. The study of Electrochemical behavior using
cyclic voltammetry and chornopotentioetry.
In conclusion, A green method is demonstrated to prepare
3-dimensional (3D) network crinkly sheets of adeninefunctionalized
spongy graphene (SFG), The synthesized
materials have been evaluated as supercapacitor materials
in 0.5 M H2SO4 using cyclic voltammetry (CV) at
different potential scan rates, and galvanostatic
charge/discharge tests at different current densities. The
SFG electrodes showed a maximum specific capacitance
of 333 F/g at a scan rate of 1 mV/s with excellent cycling retention of 102% after 1000 cycles at 200 mV/s. The
energy density was 64.42 Wh/kg with a power density of
599.8 W/kg at 1.0 A/g. Those figures of merit are much
higher than those reported for graphene-based materials
tested under similar conditions. The observed high
performance can be related to the synergistic effects of the
spongy structure and the adenine functionalization.
The nanocomposite based on Ag nanoparticles decorated
FG was synthesized successfully by simple and a green
method The synthesized materials have been evaluated as
supercapacitor materials in 0.5 M H2SO4 using cyclic
voltammetry (CV) at different potential scan rates, and
galvanostatic charge/discharge tests at different current
densities. The FG-Ag2 electrodes showed a maximum
specific capacitance of 567 F/g at a scan rate of 1 mV/s
with excellent cycling retention of 100.5% after 1000
cycles at 200 mV/s. The energy density was 89.32 Wh/kg
with a power density of 540 W/kg at 0.4 A/g. The
observed high performance can be related to the
synergistic effects of the spongy structure and the adenine
functionalization with silver nanoparticles.The nanocomposite based on of the Functionalize
graphene– HydrogenatedTiO2 hybrid nanostructure
synthesized successfully by usind Anodization and
hydrothermal process, showed a maximum specific of 401
F/g at a scan rate of 1 mV/s and 100.2% of the initial
cycle, indicating the excellent cycling stability of the
FGHTIO2 electrodes. The energy density can reach up to
78.66 Wh/Kg with a power density of 466.9 W/kg at 0.8
A/g. Note that 40.5 Wh/Kg and 1773.7 W/Kg remain
there even at a current density as high as 3 A/g.
The synthesis of heteroatom doped graphene nanosheets,
showed a maximum specific of 499/g at scan rate of 1
mV/s and excellent cycling retention 101% after 1000
cycles at 200mV/s with high energy density 98.58Wh kg-
1. To the best of our knowledge the capacitance of (N/PGNS)
would be a promising material for supercapacitors.
Further, the prepared single pot method is easy and The
improved electrochemical performance is due to the
combination of all heteroatoms the co-doping of (P and
N) graphene nanosheets synthesis.