Many higher plants have mycorrhizae associated with their roots. These structures are often essential for survival and growth (Harley & Smith 1983). Mycorrhizae are known for the abilities to enhance nutrient absorption. While nitrogen-fixing organisms are found as components of the mycorrhizosphere, mycorrhizal fungi are not presently known to fix...
Solar cells, also known as photovoltaic devices, are a class of renewable energy systems that can convert photons into electrons without the carbon dioxide emission. Short-wavelength, high-energy photons in the ultraviolet (UV) range can't be efficiently utilized by most solar cells because of the spectral mismatch. Luminescent downshifting is a...
A new group of lead free piezoelectric perovskite solid solutions, (1-x)Bi(B'B")O₃-xABO₃, were obtained via solid-state processing techniques. The solubility of unstable perovskite Bi(B'B")O₃ compounds into stable perovskite compounds was found to be related to the tolerance factor of the ABO₃ perovskite endmembers. The morphotropic phase boundary (MBP) in perovskite solid...
There is an emerging interest in developing wearable electronics as a platform, which
provides the flexibility of a wearable while maintaining its promising functionality as smart textiles. Metal-halide semiconductors are attractive materials with tunable optical and electrical properties. Researchers have widely studied and applied it for advanced
photonics and optoelectronic...
Electron and neutron irradiation effects in InGaP/GaAs single heterojunction bipolar transistors are investigated in this thesis. Devices with different emitter sizes and grown by two different growth techniques were examined. Based on the physics of heterojunction bipolar transistors and concepts of radiation damage mechanisms, the irradiation effects were analyzed. The...
Femtosecond stimulated Raman spectroscopy (FSRS) is an ultrafast vibrational technique which allows rapid collection of Raman spectra with simultaneously high temporal and spectral resolution. With the recent development of FSRS methodology, three FSRS techniques (conventional, tunable, and anti-Stokes) have been implemented in our laboratory to dissect the excited state structural...
This dissertation focuses on extending the application scope of surface enhanced infrared absorption spectroscopy to gas sensing. The method we propose is incorporating plasmonic nanostructures with nano-composite material, metalorganic framework, which can selectively preconcentrate certain gas molecules into the nanopores. The preconcentrating property is first demonstrated by applying metal-organic framework...
In the 21st century, environmental deterioration is now an indisputable fact. Reliable and economically viable electricity systems based on renewable sources are urgently needed to replace the environmentally detrimental fossil fuels. The feasibility of incorporating renewable-but-intermittent solar and wind energy heavily depends on the development of cost-effective and safe technologies,...
Naturally occurring assemblies, such as DNA and proteins, utilize intermolecular forces (i.e H-bonding and van der Waals) to assemble. Utilizing these electrostatic interactions has only just started in the past five decades to be a tool used in synthetic chemistry in what is known as supramolecular chemistry. Supramolecular chemistry has...
Hydrogen is the green fuel that can be produced from water through electrolysis and used via hydrogen fuel cells to generate electricity with zero carbon dioxide emission. The commercialization of electrolyzers and fuel cells is the critical step to achieving global carbon neutrality. However, it is severely hampered by the...