Date

2017

Document Type

Dissertation

Degree

Doctor of Philosophy

Department

Chemistry

First Adviser

Landskron, Kai

Other advisers/committee members

Vezenov, Dmitri; Xu, Xiaoji; Koel, Bruce

Abstract

Nanoporous materials are classified into three categories according to the pore sizes: microporous(< 2 nm ), mesoporous(2 – 50 nm), and macropores(> 50 nm). Due to their large surface to volume ratio and tunable pore size, nanoporous materials has gained significant research attention in recent years and has been used in many applications such as adsorbent, gas separation, catalysts, supercapacitors, drug delivery and so on.In this thesis, two aspects of nanoporous material application will be discussed. In the first part, a concept called capacitive Swing Adsorption (SSA) for carbon dioxide separation will be introduced. Unlike Pressure Swing Adsorption (PSA) and Temperature Swing Adsorption (TSA), SSA works at ambient conditions and utilizes charging and discharging of nanoporous carbon materials to alter the adsorption and desorption behaviors. In this thesis, an inexpensive gas separation device is built on top of the SSA concept. It is demonstrated that the device can reversibly capture and release CO2 from a flow of 15 % CO2 and 85 % N2 gas mixture with an energy efficiency on par with current CO2 capture techniques. With further optimizations, SSA will be promising concept for the next generation carbon dioxide capture technology.Nanoporous can be also used as unique starting materials for high-pressure material synthesis. To obtain high-pressure phases of materials, usually high-temperature high-pressure (HTHP), experiments are performed. Porous materials exhibit higher reactivity than their bulk counterparts during HTHP, thus reducing the pressure and temperature required to obtain a high pressure phase. Furthermore, the tunability of pore structures gives the potential to control the crystal size and morphology. The second part of the thesis will introduce a synthetic pathway to obtain two forms cubic boron nitride (cBN) materials: nanopolycrystalline cBN and single-crystalline cBN nanoparticles. In addition, it is also demonstrated that diamond nanowires can be obtained with the aid of a nanoporous alumina template.

Included in

Chemistry Commons

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