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1

Optical properties of soda-lime-silica glasses doped with peanut shell powder

Aktas B., Albaskar M., Yalcin S., Dogru K.

Archives of Materials Science and Engineering

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2016

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Vol. 82, nr 2

57--61

EN

Purpose: Aim of this paper is to investigate the optical properties of soda-lime-silica (SLS) glasses which doped with different quantities of peanut shell (PS) powder. Design/methodology/approach: UV-Vis and Fourier transform infrared (FTIR) spectroscopy techniques are used to determine optical properties of glass. Findings: It was observed that the colorless and transparent pure SLS glass turned dark green in color with the addition of the PS powder. The glasses doped with PS powder contents ≥1 wt.% were translucent. The maximum absorption in the UV spectrum was observed at wavelengths of 306.20, 292.40, 280.20, and 303.20 nm for SLS glasses doped with PS powder contents of 0.5, 1, 3, and 5 wt.%, respectively. The UV-Vis spectroscopy results also indicated that the amount of light transmitted by the SLS glass decreased with increasing PS powder content. The FTIR absorption spectra of the PS powder-doped SLS glasses exhibited various bands corresponding to the symmetric and asymmetric stretching of the bridging oxygen atoms between the tetrahedra. Research limitations/implications: With the addition of the PS to the SLS glass, samples turned to dark green because of Fe2O3. Future researches must focus on this matter. Originality/value: PS powders are doped to investigate optical properties of glass. Thus, glasses, which have good properties such as economically cheap, bio-friendly, are produced from food wastes.

2

Influence of solvent on the surface morphology and optoelectronic properties of a spin coated polymer thin films

Weszka J., Szindler M.M., Szczęsna M., Szindler M.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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Vol. 61, nr 2

302—307

EN

Purpose: The aim of this paper was to investigate changes in surface morphology and optoelectronic properties of MEH-PPV thin films. Thin films were prepared using spin coating method. Design/methodology/approach: The changes in surface topography was observed by the atomic force microscope AFM. The results of thin films roughness have been prepared in the software XEI. The UV/VIS spectrometer was used to investigate absorbance of the obtained thin films. Findings: Results and their analysis allow to conclude that the solvent, which is an important factor in spin coating technology has an influence on surface morphology and optoelectronic properties of MEH-PPV thin films. Practical implications: Known MEH-PPV optoeletronic properties and the possibility of obtaining a uniform thin film show that it can be a good material for optoelectronic and photovoltaic application. Originality/value: The paper presents some researches of MEH-PPV thin films deposited by spin coating method deposition on glass BK7. A MEH-PPV solution was prepared using three different solvents: chlorobenzene, chloroform and pyridine.

3

CLSM and UV-VIS researches on polyoxadiazoles thin films

Weszka J., Szindler M., Chwastek-Ogierman M., Bruma M., Jarka P.

Archives of Materials Science and Engineering

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2012

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Vol. 55, nr 2

53-61

EN

Purpose: The purpose of this paper was to analyse the surface morphology and optical properties of polyoxadiazoles thin films. Design/methodology/approach: A few different conducting polymers were dissolved in N-methyl-2-pyrrolid(in)one. Then the solutions were deposited on a glass substrate by spin coating method with a different spin rate. Changes in surface topography and optical properties were observed. A confocal laser scanning microscope CLSM Zeiss LSM 5 Exciter has been used. Photos have been taken from area of 120 x 120 microns. Findings: The analysis of images and spectra has confirmed that the quality of thin films depends upon the used polymers. It was also observed that the parameters of the spin coating method have significant effect on the morphology and the optical properties. The spin rate has got a strong impact on them. Research limitations/implications: The morphology and optical properties of polyoxadiazoles thin films has been described. This paper include description how the spin rate influence on the polymer thin films. In order to use a polymer thin film in photovoltaics or optoelectronics it must have a high internal transmission density. Further research of polymer thin films are recommended. Practical implications: The spin coating method allows to deposit a uniform thin films. It is important to know how the spin rate influence on the thin films properties. It is also important to find a new use for this group of material engineering in photovoltaic or optoelectronics devices. Originality/value: The good properties of thin films make them suitable for various applications. The value of this paper is defining the optimal parameters of spin-coating technology for polyoxadiazoles thin films. The results allow the choosing optimal parameters of the deposition process. Spin coating is a very good method to obtain thin films which are obligated to have the same thickness over the whole surface.

4

Zastosowanie reakcji kompleksowania metali porfirynami w analizie chemicznej

Kilian K., Pyrzyńska K.

Wiadomości Chemiczne

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2004

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[Z] 58, 11-12

963--981

EN

The porphyrin molecules contain four pyrrole rings linked via methane bridges. They are tetradentate ligand, in which the space available for the coordinated metal ion has a maximum diameter of approximately 3.7 Å. Porphyrins and their complexes with metal ions play important role in several biological as well as catalytic systems. They are involved in dioxygen transport and storage, photosynthesis or electron transfer. Due to strong complexing properties and catalytic behaviour, porphyrins and metaloporphyrins have found numerous applications in analytical chemistry. Several porphyrins become useful as the high sensitive chromogenic reagents. The stable complexes between transition metals and porphyrin ligands enable coordinating interaction with additional ligands above and below the molecule plane, so these compounds are used as components of membranes of ion selective electrodes in potentiometry and voltammetry. Several porphyrins find applications as optical sensors and biosensors. Due to the mixed mechanism of interaction between porphyrin macrocycle and various solutes, porphyrins find interesting applications as stationary phases in HPLC for separation of aromatic carboxylates, sulfonates, polycyclic aromatic hydrocarbons, fullerenes as well as amino acids and peptides. In capillary electrophoresis these compounds found application as the derivatizing agents. Porphyrins could be also used as a modifier in solid phase extraction technique or the selective ligands for enrichment of some transition metals.

5

Solwatochromia i barwniki solwatochromowe

Wróblewska E.K., Soroka J.A., Soroka K.B.

Wiadomości Chemiczne

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2002

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[Z] 56, 1-2

113--150

EN

The phenomenon of solvatochromism is presented, taking into account the constitution of solvatochromic dyes, the physical interpretation and mathematical description (models) of solute-solvent interaction. The discussion covers Onsager's early reactions field model and subseqent qualitative interpretation of the solvent effect on solute dipole moment change by Bayliss and McRea. Subsequently solvatochromic dyes were presented briefly as empirical polarity indicators with respect to other methods applied to this goal. Binary solvents mixtures polarity models were critically discussed, taking into account the conceptions of Langhals, Dawber, Bosh and Rosés and Skwierczyński and Connors. After this introduction Soroka's models were presented: the physicochemical V-B-HB model based on solute electronic structural changes in pure solvents and the SA-SAB-SB model of solvatochromism in binary solvent mixtures. Both models describe well the behaviour of many pure solvents, as well as the properties of a number of binary systems series including ones well known from textbooks. These models provide reliable support for advanced investigations and precise interpretation of molecular interactions in liquids.