Scientific blog
ZStarowicz Summary 
Thursday, 11 June, 2015, 16:57
Posted by Zbigniew Starowicz
Finally the studies are finished. The scientific degree of Doctor of Phylosophy has been defended. The thesis entilted "Eleboration and characterisation of plasmonic structures for photovoltaic applications" was published. Here is summary of my disertation:
Modern solar cells in their architecture more often combine the reduced amount of photoactive materials with increased energy conversion efficiency, in order to minimized the cost of solar energy. With the reduction of cell thickness in the thin-film technologies and new concepts of cells, based on nanomaterials, it is no longer possible to use heretofore known methods, such as surface texturisation or antireflection coatings, for reducing the optical losses. It is necessary to elaborate new materials and structures for coupling of light with objects in nonoscale. Such capabilities provide plasmonic metal structures.
The aim of this work was to develop and execute plasmonic structures based on silver nanoparticles that could be applied in solar cells. Basic phenomena that cause the validity of the use of such structures are strong light scattering and strengthening the near electric field around the nanoparticle at the surface plasmon resonance conditions. Silver was selected due to the occurrence of plasmon resonance in the significant from the point of view of photovoltaic wavelengths range, low parasitic absorption and good flexibility of fabrication of various types of nanostructures.
Within the presented dissertation a special emphasis was put on the methods of producing silver nanostructures potentially useful in photovoltaics and their microstructural aspects, as well as the resulting properties. Plasmonic properties strongly dependent on parameters such as the size and shape of the nanoparticles and the local environment, therefore, good control of these microstructure parameters is highly required. Three methods of preparation have been selected, which were additionally assisted by computer simulations. These were the photochemical deposition, nanoisland formation from the thin layers (Metal Island Film, MIF) and the deposition from colloids by electrostatic self-assembly process.
During the work the various research methods were used to characterize the microstructure of nanoparticles collections and structure of tested materials (SEM, AFM, TEM, XRD, XPS, Raman and infrared spectroscopy) as well as to determine optoelectronic properties (ellipsometry, UV-VIS-NIR spectroscopy, I-V characteristics, EQE). Significant progress in understanding the research field and connected issues were enabled by computer simulations for specifying the interaction of nanoparticles with light.
In terms of the photochemical methods result of this work was determination of conditions for embedding small silver nanoparticles on the surface of titanium dioxide. The average size of the nanoparticles is below 50 nm, which is changed with the change of concentration of the precursor of silver and the intensity of the laser light. The main feature of these nanoparticles was strongly strengthening short electric field. The possibility of using this kind of organic particles in the cells. Within the MIF method the deposition parameters of the Ag layers were studied as factors influencing the microstructure of resulted nanoislands. However, the main emphasis was on concept of application of nanoparticles on the front surface of the cell. For this configuration, the optimal size of the nanoparticles and surface coverage were investigated using computer simulations. Then the process of adsorption of nanoparticles from colloidal suspensions were investigated. The measured properties of obtained samples were used to re-define computer simulations taking into account actual features analyzed systems. The final result was the application of nanoparticles in silicon solar cells, yielding the highest heretofore improvement of the cell current response for structures obtained by this method.

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QE calculations MTrybula 
Wednesday, 10 June, 2015, 14:30
Posted by Marcela Trybula
QE calculations for liquid metallic solutions. In fact, vibrational density of states were determined to thermodynamic investigations.
NMR spectra of solid materials have been computed using CP2K and MM/QM methods.
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PhD report (May 2015) A. Mzyk 
Friday, 5 June, 2015, 14:56
Posted by Aldona Mzyk
The big day of the 7th May came finally. I completed my PhD story in the project and nothing has changed. I am the same person with the same dreams about real science. In the mean time I participated in EMRS Spring Meeting conference were I took a breath of fresh air. Now it is time for preparing to start the new project, so I am a little bit nervous and excited in the same time…
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May report 
Saturday, 30 May, 2015, 16:07
Posted by Zbigniew Starowicz
In May most of the time was dedicated to preparation of the final verion of the PhD theis, introduction of final corrections. The second thing was preparation the presentation for the defence and the speech.
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PhD defense MTrybula 
Thursday, 21 May, 2015, 14:17
Posted by Marcela Trybula
The manuscript was printed out. Conclusions emerging from presented in PhD thesis are as follows:
Regarding thermodynamic: "Associates" presence was confirmed using ternary interactions parameters develeoped in this work.

From thermophysics perspective, ternary effect were found, however, associates could not be confirmed

Structure: Dominance of ISRO degree has been detected for investigated liquid alloys and resulted in higher energetic satbilization of liquid phase.



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