Date of Award

Spring 6-30-2022

Document Type

Thesis

Degree Name

Bachelor of Arts (BA)

Department

Chemistry

First Advisor

Maryuri Roca

Second Advisor

Juan Navea

Abstract

A source of bioavailable iron in open oceans stems from aerosols, increasing phytoplankton growth and the sequestration of atmospheric carbon dioxide. These aerosols contain semiconductors, like titanium dioxide, which is known to increase the bioavailability and can trigger photoreduction of Fe3+. Recently, it is suspected that other metals in the aerosols also influence the release of iron. In this work, the effects of doping with iron and copper on the physical characteristics of titanium dioxide nanoparticles, since the photocatalytic potential of titanium dioxide depends on its structure and metal content (anatase vs. rutile), were explored. Titanium dioxide nanoparticles were prepared using a sol-gel synthesis with iron, copper, or both metals. These particles were characterized using x-ray diffraction, x-ray fluorescence, scanning electron microscopy, and diffuse reflectance spectroscopy. Overall, the addition of the metal(s) before or after the condensation of titanium affected the crystallinity, metal uptake, and band gap energy and wavelength of the doped semiconductor. Co-doping after titanium was added produced porous semiconductor particles with more iron and copper incorporated, a smaller conversion into rutile structure, the smallest band gap, and the largest wavelength. These doped particles will be further used to better understand the mechanism of how iron becomes bioavailable in the atmosphere.

Creative Commons License

Creative Commons Attribution-NonCommercial 4.0 International License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License

Download

Share

COinS