BIO 522

PRESENTED BY

PRINCELY, ORIOMOJOR20143204

17th December, 2015

DESALINATION OF SEAWATER WITH A SINGLE LAYER MOLYBDENUM DISULPHIDE NANOPORE

Introduction Overview of MoS2

Structure of MoS2

Properties Nanotechnology Application of MoS2

Advantages Other Nanotechnology applications of MoS2

Conclusion

OUTLINE

In the society today, producing fresh water is a great challenge. (Elimelech and Phillip, 2011; Zhao et al., 2012; Shannon et al., 2008; Fritzmann et al., 2007). Over the years reverse osmosis and electrodialysis has been use for desalination of seawater. But these separation systems have the problem of forming polarization films and by product that may generate bacteria and fouling.(A. M'nif et al., 2007). Because of this problems caused by this separation systems, alternatives separation membrane technology such as single layer Molybdenum disulphide nanopore has been experimented on for desalination of seawater.

INTRODUCTION

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Molybdenum disulphide is an inorganic compound with the formula MoS2. It is a 100% "natural" material, it is taken out of the ground. They also have a large active surface area and high reactivity (AZoNano, c.2013)MoS2 exhibits a lamellar or layer-like structure, with inter-lamellar bonding between two adjacent layers of sulfur atoms. Van der Waals forces between the layers is quite weak, meaning that the layers are easily pulled apart.

OVERVIEW OF MOLYBDENUM DISULPHIDE

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STRUCTURE OF MoS2

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http://www.rsc.org/chemistryworld/2014/01/2d-materials-graphene

MoS2

PHYSICAL PROPERTIES:

Density: 5.06 g/cm3

Molar mass: 160.07 g/molMelting point: 1,185˚cSolubility in water: InsolubleSolubility: Decomposes by aqua regia, hot sulphuric acid, nitric acid insoluble in dilute acids (AZoNano, c.2013)

PROPERTIES OF MOLYBDENUM DISULPHIDE

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CHEMICAL DATA:Chemical symbol: MoS2

Group: Molybdenum 6, Sulphur 16Electronic Configuration: Molybdenum [Kr] 4d5 5s1, Sulfur [Ne] 3s2 3p4

CHEMICAL COMPOSITION:Molybdenum 59.94 content %Sulphur 40.05 content %(AZoNano, c.2013)

CHEMICAL PROPERTIES

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Advances in nanotechnology have led to the development of a nanoporous membrane material for salt water purification. Due to this advances, a single layer MoS2 nanopore membrane was seen as effective and more energy efficient for seawater desalination. Latest trend by engineers in university of Illinois USA.

NANOTECHNOLOGY APPLICATION OF MoS2

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DIFFERENT PORE ARCHITECTURES FOR MoS2

Source: Heiranian, M. et al. Water desalination with a single-layer MoS2 nanopore

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SALT WATER PURIFICATION OF MoS2 SHEET

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The molybdenum in the center attracts water, then the sulphur on the other side pushes the water away.

The single layer sheet of MoS2 is ultra thin.

It requires less energy

It reduce operating cost

ADVANTAGE OF MoS2

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Single-Layer Molybdenum Disulphide Nanopore is used for DNA Detection(AB Farimani et al., 2015)

MoS2 is also use in the field of energy storage in lithium ion batteries.(T Stephenson et al., 2014)

Single layer MoS2 is used as transistor/semiconductor in electronics.(B Radisavljevic et al., 2011)

OTHER APPLICATIONS OF MoS2 IN NANOTECHNOLOGY.

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In this presentation we have shown that MoS2 nanopore is a promising technology for rejection of salt and water purification. Therefore MoS2 is potentially an efficient membrane for seawater desalination.

CONCLUSION

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A single layer MoS2 nanopore is thick, and its made up of two atoms molybdenum and sulphur. These two atoms together exposed to DNA bases create opportunity for DNA sequencing.

MoS2 is about 1nm thick, the thickness makes the material to be higher to graphene in terms of signal/noise intensity for DNA detection.

MoS2 FOR DNA DETECTION

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DNA TRANSLOCATION THROUGH A MoS2 NANOPORE

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SIGNAL NOISE RATIO OF MoS2 NANOPORE.

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The unique properties of molybdenum disulphide engender a versatility that has enabled its use in a wide range of scientific fields. The application of MoS2 to the Field of energy storage in lithium ion batteries is a promising technology, it compensate for it intermediate insertion voltage with a high reversible capacity and an excellent rate capability.

APPLICATION OF MoS2 NANOCOMPOSITES ON LITHIUM ION BATTERY.

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MOLECULAR MODELS OF MoS2 ON LITHIUM ION BATTERY.

Molecular models of (a) 2H–MoS2. (b) Lithiated 2H–MoS2 showing a 5% lattice expansion in the c-direction and a-direction due to intercalation. (c) Lithiated 1T–MoS2 showing lithium ions occupying octahedral interstices. (d) 3R–MoS2 (e) Li2S 17

XRD scans of MoS2 electrode at various states of charge. (a) (Bottom) as received, and (top) after discharge to 0.01 V. Peaks marked by *are from the copper current collector.172 (b) After discharge to 0.01 V (c) After recharge to 3.0 V

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A. M'nif, S. Bouguecha, B. Hamrouni, and M. Dhahbi, “Coupling of membrane processes for brackish water desalination,” Desalination, vol. 203, no. 1–3, pp. 331–336, 2007. View at Publisher · View at Google Scholar · View at Scopus

Elimelech, M. & Phillip, W. A. The future of seawater desalination: energy,

Fritzmann, C., Lowenberg, J., Wintgens, T. & Melin, T. State-of-the-art of reverse osmosis desalination. Desalination 216, 1–76 (2007).

http://www.azonano.com/article.aspx?ArticleID=3351

REFERENCES

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http://www.rsc.org/chemistryworld/2014/01/2d-materials-graphene

Radisavljevic, B., Radenovic, A., Brivio, J., Giacometti, V. & Kis, A. Single-layer MoS2 transistors. Nature Nanotech. 6, 147–150 (2011).

Shannon, M. A. et al. Science and technology for water purification in the coming decades. Nature 452, 301–310 (2008).

Technology, and the environment. Science 333, 712–717 (2011).

Zhao, S. F., Zou, L., Tang, C. Y. Y. & Mulcahy, D. Recent developments in forward osmosis: opportunities and challenges. J. Membr. Sci. 396, 1–21 (2012).

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THANK YOU

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