“Introduction to Nanotubes and Nanotube Membranes”
(Ms. A. V. Patel)
Chemical Engineering Department
Institute of Technology
Nirma University of Science and Technology
Ahmedabad – 382 481
This is to certify that Mr. Vivek K Pramanick , Roll No. 04BCH026, of B. Tech. Sem. VI has successfully completed the report of seminar on “Introduction to Nanotubes and Nanotube membranes”.
Date: 17th April, 2007
Guide: Ms. A. V. Patel
Head of the Department: Prof. A. P. Vyas
• Introduction to Carbon Nanotubes
• Structure of MWNTS and SWNTs
• Properties of Carbon Nanotubes
• Nanotube Membranes
I am thankful to Ms. A. V. Patel for guiding me throughout the preparation of this seminar and providing me with useful data and guidance which has helped me a lot. I am also grateful to the faculties of Chemical Engineering department for guiding me through the seminar preparation and the University for providing me the platform to present this seminar.
Carbon nanotubes are allotropes of carbon. They are one-atom thicksheet of graphite rolled up into a seamless cylinder with diameter of the order of a nanometer. Their name is derived from their size, since the diameter of a nanotube is on the order of a few nanometers (approximately 50,000 times smaller than the width of a human hair), while they can be up to several millimeters in length. They exhibit extraordinary strength and unique electrical properties, and are efficient conductors of heat. In this paper, a brief introduction to carbon nanotubes, its types, structure, properties, synthesis and applications are discussed. Further, one of the applications of carbon nanotube- nanotube membranes is discussed. It is found that for nanotube membranes the gas permeabilities are 1,000 percent and water permeabilities are 10,000 percent greater than for polycarbonate membranes. These membranes could be used in desalination and demineralization. Salt removal from water, commonly performed through reverse osmosis, uses less permeable membranes, requires large amounts of pressure and is quite expensive. These more permeable nanotube membranes could reduce the energy costs of desalination by up to 75 percent compared to conventional membranes used in reverse osmosis. Carbon nanotubes (CNTs) are allotropes of carbon. A carbon nanotube is a one-atom thicksheet of graphite (called graphene) rolled up into a seamless cylinder with diameter of the order of a nanometer. This results in a nanostructure where the length-to-diameter ratio exceeds 10,000. Such cylindrical carbon molecules have novel properties that make them potentially useful in a wide variety of applications in nanotechnology, electronics, optics and other fields of materials science. They exhibit extraordinary strength and unique electrical properties, and are efficient conductors of heat. Nanotubes are members of the fullerene structural family, which also includes buckyballs. Whereas buckyballs are spherical in shape, a nanotube is cylindrical, with at least one end typically capped with a hemisphere of the buckyball structure. Their name is derived from their size, since the diameter of a nanotube is on the order of a few nanometers (approximately 50,000 times smaller than the width of a human hair), while they can be up to several millimeters in length. There are two main types of nanotubes: single-walled nanotubes (SWNTs) and multiwalled nanotubes(MWNTs). The nature of the bonding of a nanotube is described by applied quantum chemistry, specifically, orbital hybridization. The chemical bonding of nanotubes are composed entirely of sp2 bonds, similar to those of graphite. This bonding structure, which is stronger than the sp3 bonds found in diamond, provides the...