Engineering Tunable Colloidal Nanostructures for Light Energy Harvesting

nanoenergy;solution-processed;optoelectronics;energy harvesting;Electrical Engineering

Arinze, Ebuka S.Thon, Susanna ;

Johns Hopkins University

关键词: nanoenergy;    solution-processed;    optoelectronics;    energy harvesting;    Electrical Engineering;   

Others  :  https://jscholarship.library.jhu.edu/bitstream/handle/1774.2/60135/ARINZE-DISSERTATION-2018.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: JOHNS HOPKINS DSpace Repository

【 摘 要 】

Colloidal nanomaterials, such as semiconductor quantum dots and plasmonic metal nanoparticles, are of interest for various optoelectronic applications due to their size-tunable optical properties, unique electronic structures, and low-cost fabrication techniques. As the physical footprint of emerging optoelectronic device components continues to shrink, colloidal nanomaterials have the potential to enable advances in fields such as low-power computing, renewable energy generation and storage, and biosensing and medicine, due to their small size, earth-abundance, and novel functionality. This thesis focuses on engineering these nanostructures for energy harvesting technologies, such as solar cells, photodetectors and photocatalysts. This is achieved by combining modeling, nanofabrication, and advanced optical and electrical characterization techniques. The study is implemented in three sections. The first involves engineering these nanostructures for solution processed solar cells. Using optimization algorithms combined with thin film interference modeling, we developed a method for producing arbitrary spectral profiles in solar cells structures for potential applications in building- and window-integrated power generation. Similarly, by using photonic band engineering in strongly absorbing materials, we developed and analyzed a new strategy for tuning the spectral selectivity of optoelectronic films. Additionally we critically evaluate the prospects for plasmonic enhancements in solution-processed thin-film solar cells by developing an intuitive effective medium model for embedded plasmonic nanostructures in photovoltaic thin films. The next section involves investigating these nanostructures for photon detection applications. One study involves using a one-step solution-based growth technique to grow antimony selenide nanowires. This enables the growth of high-quality antimony selenide nanostructures from a molecular ink directly on flexible substrates for high-performance near-infrared photodetectors thus providing a route for low-cost, flexible, and broadband photon detection. The other study demonstrates high responsivity visible blind photodetectors based on nanoheterojunction films, thus representing a viable path for building UV cost-effective optoelectronic devices Finally, the last section includes designing, developing and characterizing new plasmonic-catalytic systems based on earth-abundant and cost-effective nanomaterials such as aluminum. We present the first photophysical characterization of plasmonic aluminum nanoparticles, and identify tuning strategies such as surface modifications for various niche applications. These three sections culminate in creating a sustainable route to building both an energy-efficient and scalable-materials platform for the next generation of nanotechnology-based optoelectronic devices for energy applications.