Sökning: "exciton binding energy"
Visar resultat 1 - 5 av 6 uppsatser innehållade orden exciton binding energy.
1. Photophysics of the polymer acceptor PF5-Y5 in organic photovoltaics : A first principles theory based study
Master-uppsats, Karlstads universitet/Institutionen för ingenjörsvetenskap och fysik (from 2013)Sammanfattning : Non-fullerene Acceptors (NFAs) have gathered a great deal of interest for use inorganic photovoltaics (OPVs) due to recent breakthroughs in their power conversion efficiency and other advantages they offer over their Fullerene-based counterparts. In this work, a new promising non-fullerene polymer acceptor, PF5-Y5, have been studied using density functional theory and time-dependent density functional theory; and the effects that oligomer length, geometry relaxation and exchange-correlation interaction has on the exciton binding energies (the difference between optical and fundamental energy gaps) have been investigated. LÄS MER
2. Charge transfer states at polymer solar cell interfaces : Insights from atomic-scale modeling
Master-uppsats, Karlstads universitet/Institutionen för ingenjörsvetenskap och fysik (from 2013)Sammanfattning : Organic solar cells (OSCs) based on non-fullerene acceptors (NFAs) have attracted a great deal of attention in recent years due to their rapidly increasing efficiency and enormous potential. In this work, the optical and electronic properties of systems containing the very promising non-fullerene acceptor PYT have been thoroughly studied with the use of the density functional theory (DFT) and the time-dependent density functional theory (TDDFT). LÄS MER
3. Evaluation of Zinc Oxide Nano-Microtetrapods for Biomolecule Sensing Applications
Master-uppsats, KTH/Funktionella material, FNMSammanfattning : Zinc oxide (ZnO) is a well-known II-VI semiconductor material that has gained renewed interest in the past decade due to the developments of growth technologies and the availability of high-quality ZnO bulk single crystals. Owing to a wide direct band gap (3. LÄS MER
4. Time-resolved study of charge photo-generation in polymer-based solar cells with low driving force
Magister-uppsats, Lunds universitet/Fysiska institutionenSammanfattning : Organic polymer-based solar cells recently attracted much attention as an efficient and inexpensive light-to-electricity conversion solution. However, the mechanism behind charge generation processes in organic materials is still not fully understood due to complex nature of carbon-based compounds. LÄS MER
5. Investigation of ZnO nanorods for UV detection
Uppsats för yrkesexamina på avancerad nivå, KTH/Skolan för informations- och kommunikationsteknik (ICT)Sammanfattning : In recent years, there has been increasing interest in ZnO semiconductors for optoelectronic application in the UV wavelength region due to its large exciton binding energy of 60 meV and wide bandgap energy of 3,37 eV at room temperature. One-dimensional ZnO nanostructures such as nanorods or nanowires have been considered as promising candidates for UV sensing and detecting applications owing to its high surface to volume ratio. LÄS MER
