Masters Theses

Abstract

"Carbon nanotubes are being studied for a variety of applications due to their outstanding mechanical, chemical, electrical, and optical properties that make them interesting in different areas. Nowadays, different methods to modify the structure of the nanotubes are being developed in order to expand the application fields of such materials. In this work, palladium nanoparticles were directly produced and supported on multi-walled carbon nanotubes (MWCNT) by gamma irradiation. A solution with a 2:1 water-isopropanol ratio was prepared and mixed with palladium chloride as precursor of palladium ions. Radiolysis of water produces certain species that reduce the ions down to a zero-valent state. However, strong oxidizing agents are also produced during irradiation. Hence a scavenger, such as a secondary alcohol, has to be added to the solution in order to balance the reaction. Coalescence of the metal nanoparticles was controlled by the addition of the stabilizer sodium dodecylsulfate (SDS). The size and distribution of the nanoparticles on the nanotubes were studied at different surfactant concentration and radiation doses at a fixed concentration of palladium chloride. After irradiation, X-ray photoelectron spectroscopy revealed the palladium peaks Pd3d5/2 and Pd3d3/2 at binding energies of 335.9 and 341.1eV, respectively, which are characteristic of metallic palladium (Pd⁰), thus confirming the successful reduction of Pd⁺² to Pd⁰. Scanning transmission electron microscopy, and transmission electron microscopy were used for morphological characterization of the nanostructure Pd nanoparticles-CNTs. Nanoparticles obtained for doses between 10 and 40 kGy, ranged in size 5-30 nm. The smaller nanoparticles were obtained at the higher doses and vice versa. Histograms of particle size distributions at different doses are presented"--Abstract, page iii.

Advisor(s)

Castaño, Carlos H.

Committee Member(s)

Usman, Shoaib
Nath, Manashi
Kumar, A. S. (Arvind S.)

Department(s)

Nuclear Engineering and Radiation Science

Degree Name

M.S. in Nuclear Engineering

Sponsor(s)

Missouri University of Science and Technology. Energy Research Development Center
Missouri University of Science and Technology. Research Board

Publisher

Missouri University of Science and Technology

Publication Date

Fall 2011

Pagination

ix, 78 pages

Note about bibliography

Includes bibliographical references (pages 57-58).

Rights

© 2011 Jessika rojas Marin, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Subject Headings

Gamma rays -- Research
Hydrogen -- Storage
Irradiation
Nanoparticles
Palladium

Thesis Number

T 9942

Print OCLC #

794688415

Electronic OCLC #

774037183

Download

Share

 
COinS