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Charge transport in halide perovskites affected by the surface treatment and metalization.
Šlechta, Miroslav ; Belas, Eduard (advisor) ; Grym, Jan (referee)
In this thesis, I study charge transport in halide perovskites. This is done using the characterization method, which here is the I-V characteristics. It studies the effect of current and voltage on the prepared sample, also at different temperatures. A significant sensitivity of the material to the measurement history was found. Derived evaluations of this measurement technique further provide possibilities for the detection of hysteresis behavior as well as the evaluation of measurements over time to determine the temporal stability of carrier collection. This also proved the phenomenon of electromigration of defects. Furthermore, transport parameters were calculated from the time measurements, which point to their non-monotonic development in increasing temperatures. A theoretical model explaining such behavior was proposed as a possibility for further research on perovskites and development of this topic.
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Preparation and characterization of silicon-based materials
Šlechta, Miroslav ; Dian, Juraj (advisor) ; Jelínek, Ivan (referee)
Title: Preparation and characterization of silicon-based materials Author: Miroslav Šlechta Department: Department of Chemical Physics and Optics Supervisor: doc. RNDr. Juraj Dian, Csc., Department of Chemical Physics and Optics Abstract: Porous silicon is nanostructured material based on silicon. He was prepared by anodic etching of crystalline silicon in hydrofluoric acid. Physical and chemical properties of porous silicon nanocrystals resulting from the dimensions, which range from units to tens of nanometers. For nanostructured silicon compared to crystalline silicon, exhibit unique properties that depend on the degree of quantum dimensional phenomena and phenomena on its large internal surface. Suitable choice of the silicon substrate, particularly in terms of conductivity and crystallographic orientation, and technological conditions (in particular electrolyte composition, the etching time and current density) can be prepared nanostructured materials of different pore sizes - macroporous, mesoporous and microporous silicon and varying representation Si-O and Si-H bonds. Morphology and chemical composition of the surface of porous silicon allows to think of it as a suitable material for a range of applications - particularly chemical sensors and biosensors, optoelectronics and biomedical applications....
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Specification of Short Sea Shipping and its use as an alternative to truck transportation
Šlechta, Miroslav ; Novák, Radek (advisor) ; Marek, Jiří (referee)
The goal of the thesis is to find out wether it's possible to consider short sea shipping as an adequate alternative to trucking. The thesis describes the specifics of Short Sea Shipping and its main maritime route. It also compares the advantages and disadvantages of short sea shipping and truck transportation. Furthermore the thesis assesses their economical aspects and the potential risks associated with these means of transport. The conclusion of the thesis recommends the suitable routes and comes up with other circumstances that should be considered while using Short Sea Shipping as a trucking alternative.
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