FIRST PRINCIPLE STUDIES ON STRUCTURAL STABILITY OF REDUCED GRAPHENE OXIDE UNDER HIGH PRESSURE
A PROJECT REPORT
Submitted by
CANDIDATE NAME
Reg.No. 1234567890
Department of Mathematics SRM University, Chennai
Under the guidance of
GUIDE NAME
Assistant Professor
Department of Mathematics SRM University, Chennai
in partial fulfilment of the requirement
for the award of the Degree of
in
MATHEMATICS
of
FACULTY OF SCIENCE AND HUMANITIES
S.R.M. Nagar, Kattankulathur-603203, Kancheepuram District APRIL 2017
BONAFIDE CERTIFICATE
Certified that this project report titled “FIRST PRINCIPLE STUDIES OF GRAPHENE OXIDE AND REDUCED GRAPHENE OXIDE UNDER HIGH PRESSURE” is the bonafide work of “Mallidi Venkata Reddy [Reg No: 1231210037]”, who carried out the project work under my supervision. Certified further, that to the best of my knowledge the work reported herein does not form any other project report or dissertation on the basis of which a degree or award was conferred on an earlier occasion on this or any other candidate.
(Signature of H.O.D) (Signature of Guide)
Dr. A.GOVINDARAJAN GUIDE NAME
SRM University SRM University Chennai Chennai
(Signature of Dean Sciences)
Dr. D. JOHN THIRUVADIGAL
Dean (Sciences) SRM University
Chennai
ABSTRACT
The effect of pressure on reduced Graphene Oxide (rGO) was performed using first principle calculations. At ambient conditions rGO exhibits semi conducting property. The electrical and other properties with the application of pressure can be justified by structural stability of the systems. Structural stability of rGO was correlated with Mott Hubbard Criterion. Here, the density of states with respect to the position of fermi level is correlated with structural stability of rGO. Bang gap of rGO was found to be 0.45 eV. Moreover, the band structure of rGO does not show much variation with pressure up to 21GPa which proclaims that rGO has high structural stability at high pressure. For the band structure calculations at ambient and various pressures we have used Quantum Espresso package which works plane wave basis sets and pseudo potentials to calculate the properties of reduced graphene oxide under high pressure.
ACKNOWLEDGEMENTS
I would like to express my deep and sincere gratitude to my guide Dr. V. Kathirvel it is an honour for me to have project preparations.
Student Name
TABLE OF CONTENTS
CHAPTER NO. TITLE PAGE NO.
ABSTRACT ii
ACKNOWLEDGEMENTS iii
TABLE OF CONTENTS iv
LIST OF FIGURES vi
LIST OF TABLES vii
LIST OF SYMBOLS ix
1 INTRODUCTION 1
1.1 EFFECT OF PRESSURE
1.1.1 LATTICE EFFECT
1.1.2 ELECTRONIC EFFECT
2 CALCULATIONS 3
2.2 FLOW CHART
2.3 DETAILED THEORY
iv
3 RESULTS AND DISCUSSIONS 4
4 CONCLUSION 5
5 FUTURE WORK 6
v
LIST OF FIGURES
FIGURE NO. DESCRIPTION PAGE NO.
1 PRESSURE VARIANT BAND VARIATION 11
2 BAND STRUCTURE AND DENSITY OF 15
3 SCHEMATIC DIAGRAM OF GRAPHITE 16
4 BAND STRUCTURE AND DENSITY OF 18 STATES OF GRAPHENE
vi
LIST OF TABLES
TABLE NO. DESCRIPTION PAGE NO.
STABILITIES OF CARBON ALLOTROPES
vii
LIST OF ABBREVIATIONS
ABBREVIATION DESCRIPTION
RGO REDUCED GRAPHENE OXIDE GO GRAPHENE OXIDE
SCF SELF CONSISTENT FEILD
DFT DENSITY FUNCTIONAL THEORY
viii
LIST OF SYMBOLS
SYMBOL DESCRIPTION
ix
INTRODUCTION
Carbon is one of the most intriguing elements in the Periodic Table. It forms many allotropes, some known from ancient times (diamond and graphite) and some discovered 10-20 years ago (fullerenes and nanotubes).
More generally, graphene represents a conceptually new class of materials that are only one atom thick and, on this basis, offers new inroads into low-dimensional physics that has never ceased to surprise and continues to provide a fertile ground for applications [16].
1.1 EFFECT OF PRESSURE
Pressure is a thermodynamic unit like temperature. effect of pressure is more significant than effect of temperature. shifting of the Fermi level itself to higher values.[1]
1.1.1 LATTICE EFFECT
1
1.1.2 ELECTRONIC EFFECT
2
CALCULATION DETAILS
2.1 QUANTUM ESPRESSO
3
We have calculated the density of states and band structure of reduced graphene oxide at ambient conditions and high pressure. Position of Fermi energy line has been
4
CONCLUSION
5
FUTURE WORK
High pressure work will be carried out on the structure Graphene Oxide to observe
the stability
6
REFERENCES
[2] Scientific Background on the Nobel Prize in Physics 2010 graphene compiled by the Class for Physics of the Royal Swedish Academy of Sciences.
