• Login
• Admin

Cull, William J. (2024) Inorganic Materials Confined in Carbon and Boron Nitride Nanotubes. PhD thesis, University of Nottingham.

PDF (Thesis - as examined) - Repository staff only until 24 July 2026. Subsequently available to Anyone - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader Available under Licence Creative Commons Attribution. Download (182MB)

Abstract

The use of carbon nanotubes (CNTs) for the encapsulation of chemical species and the formation of functional nanocomposite materials has been well documented. Conversely, the utilisation of boron nitride nanotubes (BNNTs) for the same purpose has remained relatively understudied. The work presented in this thesis investigates the effect of the chemical composition of the encapsulating nanotube (NT) on both the properties of the resultant nanocomposite material and the ability to probe the chemical and physical state of the encapsulated species. Synthetic methods to produce a variety of CNT and BNNT based nanocomposite materials are reported, alongside rigorous analysis of these materials by aberration-corrected transmission electron microscopy (AC-TEM) and a variety of other spectroscopic and analytical methods.

The encapsulation of selenium (Se) inside CNTs of varying diameters revealed previously undiscovered conformations of Se, including linear single atom chains. When Se was encapsulated by BNNTs it was found that irradiation of filled BNNTs with the electron beam of a TEM could be used to reduce the diameter of both the BNNT and encapsulated Se. Additionally, low-loss scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS) was utilised to experimentally determine the optical band gap of BNNT encapsulated Se nanowires.

Fourier transform infrared (FT-IR) spectroscopy of various metal carbonyls encapsulated inside CNTs and BNNTs was performed. Comparison between experimental and computational FT-IR spectra revealed information regarding the degree of physisorption and the mobility of encapsulated species.

Two varieties of indium selenide (InxSey) were successfully encapsulated by CNTs. One of these varieties, β-In2Se3 was shown to undergo a thermally induced phase change at 400 °C, as confirmed by an in-situ AC-TEM heating experiment. Encapsulation of β-In2Se3 by BNNTs was also achieved, with low-loss STEM-EELS analysis experimentally determining the optical band gap the nanoconfined species.

Finally, vanadyl acetylacetonate (VO(acac)2), a molecular paramagnet, was encapsulated inside both CNTs and BNNTs to assess the impact of type of NT on the ability to analyse the magnetic properties of encapsulated material. The strong magnetic response from host CNTs appeared to obscure magnetic signals from encapsulated VO(acac)2. Conversely, BNNTs exhibited very little magnetic character, allowing for detection of encapsulated VO(acac)2 by electron paramagnetic resonance (EPR) spectroscopy. Additionally, optically detected magnetic resonance (ODMR) analysis of fluorescent nanodiamonds (FNDs) was utilised to perform nanoscale magnetic sensing on VO(acac)2 inside BNNTs, with further work hoping to improve the accuracy of these sensing measurements in the future.

Item Type:	Thesis (University of Nottingham only) (PhD)
Supervisors:	Khlobystov, Andrei N. Patanè, Amalia George, Michael W.
Keywords:	Chemistry, Nanotechnology, Nanoscience, Nanotubes, Electron Microscopy, Low Dimensional Materials, Nanomaterials
Subjects:	Q Science > QD Chemistry > QD 71 Analytical chemistry R Medicine > R Medicine (General) > R855 Medical technology. Biomedical engineering. Electronics
Faculties/Schools:	UK Campuses > Faculty of Science > School of Chemistry
Item ID:	76946
Depositing User:	Cull, William
Date Deposited:	14 Aug 2024 14:05
Last Modified:	14 Aug 2024 14:05
URI:	https://eprints.nottingham.ac.uk/id/eprint/76946

Actions (Archive Staff Only)

Edit View