1. EEE2056 Physical Electronic Presented by Oh Chin Wei 1141124883 Electronic Engineering What are covered in these slides? Graphene Structures Properties Applications Risks Future applications Summary

2. Graphene Discovered by Kostya Novoselov and Andre Geim. Monolayer of carbon atom in hexagonal honeycomb lattice. First material in 2D form in the world. Wonder material. Structure Only one atom thick. Crystalize structure with honeycomb lattice also known as hexagonal lattice. Arranged in regular, endless repeating arrangement Hence, form a layer of carbon atom (2D sheet).

3. Properties Strongest compound in the world. High stiffness Thinnest material Bendable and stretchable Excellent conductor of heat and electricity Zero overlap semi-metal High transparency Versatile

4. Applications Superconductor Sensors include ultrasensitive gas sensor and bio-sensing devices Improved lithium battery Touch screen for tablets and phones Graphene junction field-effect transistor (G-FET) Photonic devices Biomedicine in terms of transportation of medicine stems, tissue engineering and biological agents

5. Risks Graphene as light and transparent material could be dangerous – Potentially be inhaled and can damage respiratory system – Graphene flakes too big for white blood cells to engulf Hazardous in non-watery areas – Contribute to chemically induced instability in dry areas One-atom layered graphene can be lethal or toxic to human body in cellular level – Sharp edges can easily pierce cell membrane in human body – Lead to disruption of normal cellular activities which can be fatal

6. Future Applications New breakthrough by researchers from North Carolina State University New phase of solid carbon called Q-carbon Formed diamond-structured application at room temperature and at ambient atmospheric pressure in air Using Q-carbon, able to create application to be used in pharmaceutical and biotechnological fields Microdiamonds produced directly from a Q-Carbon substrate after the laser treatment. Taken from AIP/ALP Materials.

7. Summary Graphene only one atom-thick Strongest and thinnest compound, yet high transparency The only material exist in 2D Might be able to substitute silicon in future Highly used in engineering field and biomedical field Useful but many risks still remain unknown Known risks include dangerous to human at cellular level and hazardous in non- watery areas It is known as wonder material in this era despite of unknown risks