Michal Krompiec

Synthesis, materials characterization and opto(electrical) properties of unsymmetrical azomethines with benzothiazole core

Optical (UV-vis and photoluminescence) properties of two soluble organic molecules based on azomethines with benzothiazole core (BTA1 and BTA2) were reported. The structures of both compounds are characterized by means FTIR, (1)H NMR, and (13)C NMR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. The investigated compounds emitted blue light. Influence of excitation wavelength and concentration on maximum and intensity of emission of BTA1 and BTA2 was found. Electrochemical properties of the compounds were studied by differential pulse voltammetry. Introduction of fluorine moieties (BTA1) resulted in lower energy band gap (E(g)) of approximately ∼0.5 eV, whereas BTA2 showed E(g) of ∼2.8 eV. The devices comprised of BTA1 with P3HT:PCBM (1:1:1) showed an open circuit voltage (V(OC)) of 0.40 V, a short circuit current (J(SC)) of 1.19 mA/cm(2), and a fill factor (FF) of 0.23, giving a power-conversion efficiency (PCE) of 0.10% under AM1.5 G irradiation (100 mW/cm(2)).

Polyazomethine with vinylene and phenantridine moieties in the main chain: Synthesis, characterization, opto(electrical) properties and theoretical calculations

The opto(electrical) properties and theoretical calculations of polyazomethine with vinylene and phenantridine moieties in the main chain were investigated in the present study. 2,5-Bis(hexyloxy)-1,4-bis[(2,5-bis(hexyloxy)-4-formyl-phenylenevinylene]benzene was polymerized in solution with 3,8-diamino-6-phenylphenanthridine (PAZ-PV-Ph). The temperatures of 5% weight loss (T 5%) of the polyazomethine was observed at 356 °C in nitrogen. Electrochemical properties of thin film of the polymer were studied by differential pulse voltammetry. The HOMO level of the PAZ-PV-Ph was at −4.97 eV. The energy band gap (E g) was detected of approximately ∼1.9 eV. Energy band gap (E gopt) was additionally calculated from absorption spectrum and absorption coefficient α. The absorption UV-vis spectra of polyazomethine recorded in solution showed a blue shift in comparison with the solid state. HOMO-LUMO levels and E g were additionally calculated theoretically by density functional theory and molecular simulations of PAZ-PV-Ph are presented. Current density–voltage (J–U) measurements were performed on ITO/PAZ-PV-Ph/Al, ITO/TiO2/PAZ-PV-Ph/Al and ITO/PEDOT/PAZ-PV-Ph:TiO2/Al devices in the dark and during irradiation with light (under illumination of 1000 W m−2). The polymer was tested using AFM technique and roughness (R a, R ms) along with skew and kurtosis are presented.

The synthesis, molecular, crystal, and electronic structures of [ReBr2(O)(OCH3)(PPh3)2]

[ReBr2(O)(OCH3)(PPh3)2] has been obtained in the reaction of [ReBr3O(PPh3)2] or [ReBr2(η2-N2COPh-N′,O)(PPh3)2] with an excess of methanol. [ReBr2O(OMe)(PPh3)2] crystallizes in the triclinic space group P-1. The complex was characterized by infrared, UV-Vis, and 1H NMR spectra. The electronic structure of the obtained compound has been calculated using the DFT/TD–DFT method.