Examination of the effect of selected factors on the photovoltaic response of dye-sensitized solar cells

The impact of photoanode preparation on the photovoltaic performance of dye-sensitized solar cells was investigated. The effects of titanium dioxide layer thickness, type of solvent and immersion time used for photoanode fabrication, and addition of coadsorbents and a cosensitizer on photon-to-current conversion efficiency and photovoltaic parameters were studied. Commercially available N719 and dyes prepared in our research group, 5,5′-bis(2-cyano-1-acrylic acid)-2,2′-bithiophene and 2-cyano-3-(2,2′:5′,2″-terthiophen-5-yl)acrylic acid, were applied as sensitizers. The effect of studied factors on UV–vis properties and morphology, that is, the root-mean-square roughness of the photoanode, was examined and correlated with the photovoltaic response of the constructed devices. Additionally, the amount of dye molecules adsorbed to the TiO2 was investigated. It was found that all considered factors significantly impacted photovoltaic parameters. Also, the photoanode stability was tested by measuring photovoltaic parameters after 14 months

Effect of polythiophene content on thermomechanical properties of electroconductive composites

The thermal, mechanical and electrical properties of polymeric composites combined using polythiophene (PT) dopped by FeCl3 and polyamide 6 (PA), in the aspect of conductive constructive elements for organic solar cells, depend on the molecular structure and morphology of materials as well as the method of preparing the species. This study was focused on disclosing the impact of the polythiophene content on properties of electrospun fibers. The elements for investigation were prepared using electrospinning applying two substrates. The study revealed the impact of the substrate on the conductive properties of composites. In this study composites exhibited good thermal stability, with T5 values in the range of 230–268 °C that increased with increasing PT content. The prepared composites exhibited comparable PA Tg values, which indicates their suitability for processing. Instrumental analysis of polymers and composites was carried out using Fourier Transform Infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and scanning electron microscopy (SEM)

Effect of polyaniline content and protonating dopants on electroconductive composites

Elastic constructive elements prepared by electrospinning using polyacrylonitrile/polyaniline (PAN/PANI) electroconductive composites were prepared and investigated in terms of their thermal and mechanical properties. This study was focused on the impact of the type of counterion of polyaniline and the PANI content in composites on the thermal, conductive and morphological properties of electrospun fibers. In this study, composites obtained from PANI doped with sulfuric acid showed the highest conductivity, and composites obtained from PANI doped with hydrochloric acid showed the highest thermal stability. All obtained composites exhibited good thermal stability, with T5 values in the range of 230–268 °C that increased with increasing PANI content. The prepared composites exhibited comparable PAN Tg values, which indicates their suitability for processing. Instrumental analysis of polymers and composites was carried out using UV–visible spectroscopy, thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical thermal analysis and scanning electron microscopy

Impact of TiO2 nanostructures on dye-sensitized solar cells performance

The effect of TiO2 nanostructures such as nanoparticles, nanowires, nanotubes on photoanode properties, and dye-sensitized solar cells photovoltaic parameters were studied. The series of dye-sensitized solar cells based on two dyes, that is, commercially N719 and synthesized 3,70- bis(2-cyano-1-acrylic acid)-10-ethyl-phenothiazine were tested. Additionally, the devices containing a mixture of this sensitizer and chenodeoxycholic acid as co-adsorbent were fabricated. The amount of adsorbed dye molecules to TiO2 was evaluated. The prepared photoanodes with different TiO2 nanostructures were investigated using UV-Vis spectroscopy, optical, atomic force, and scanning electron microscopes. Photovoltaic response of constructed devices was examined based on currentvoltage characteristics and electrochemical impedance spectroscopy measurements. It was found that the highest UV-Vis absorption exhibited the photoanode with nanotubes addition. This indicates the highest number of sensitizer molecules anchored to the titanium dioxide photoanode, which was subsequently confirmed by dye-loading tests. The highest power conversion efficiency was (6.97%) for solar cell containing nanotubes and a mixture of the dyes with a co-adsorbent

New thiophene imines acting as hole transporting materials in photovoltaic devices

ASAP Article - Articles ASAP (as soon as publishable) are posted online and available to view immediately after technical editing, formatting for publication, and author proofing.Five new unsymmetric thiophene imines end-capped with an electron-donating amine (−NH2) group were obtained using a simple synthetic route, that is, the melt condensation of 2,5-diamino-thiophene-3,4-dicarboxylic acid diethyl ester with commercially available aldehydes. Their thermal stability and electrochemical and photophysical (absorption (UV−vis) and photoluminescence (PL)) properties were examined and density functional theory calculations were performed. The imines were thermally stable above 200 °C. They underwent reduction and oxidation processes and exhibited an energy band gap electrochemically estimated between 1.81 and 2.44 eV. They absorbed radiation from the UV and visible range to 480 nm and showed weak light emission. These compounds were investigated as hole transporting materials in solar cells with the structure FTO/b-TiO2/m-TiO2/perovskite/imine/Au. The highest photoelectric conversion efficiency was observed for compounds with a morpholine derivative substituent

Patient counselling service with the use of pictograms as the example of pharmacist intervention to improving compliance and medicine safety

Background: Pharmaceutical pictograms have been designed to help communicate medication instructions to patients. Pictograms used within a patient counseling service can significantly improve medication compliance and adherence. The study aimed to assess the improvement of adherence to therapy with the use of pictogram intervention in comparison to standard pharmacy practice in community pharmacies. Methods: Pictograms informing about the proper way of using metoprolol prolonged release tablets were designed to be used on the packages of the drug in community pharmacies. Pharmacies belonging to a pharmacy practice-based research network were randomly assigned to a group using pictograms when dispensing the drug or one following their normal practice. At the first visit, all patients answered a structured questionnaire about their medication behavior in the preceding 7 days. The same questions were asked 4 weeks later to follow-up treatment adherence change and compare studied groups. Descriptive statistics was used to analyze the data, and the McNemar test was used to compare categorical data at baseline and follow-up. Results: Of a total of 253 patients screened, 117 and 104 patients completed the study in the standard practice and pictogram groups, respectively. The use of pictograms significantly improved medication adherence in the following areas: not omitting doses (p < 0.0001), not crushing tablets (p = 0.004), number of tablets/day (p = 0.49), and time of use (p = 0.001), compared to the standard practice group. Conclusions: Our results suggest that pictograms are effective in conveying messages about the proper way of using medications, and they increase treatment adherence, in comparison to standard dispensing practice

New benzo[h]quinolin-10-ol derivatives as co-sensitizers for DSSCs

New benzo[h]quinolin-10-ol derivatives with one or two 2-cyanoacrylic acid units were synthesized with a good yield in a one-step condensation reaction. Chemical structure and purity were confirmed using NMR spectroscopy and elemental analysis, respectively. The investigation of their thermal, electrochemical and optical properties was carried out based on differential scanning calorimetry, cyclic voltammetry, electronic absorption and photoluminescence measurements. The analysis of the optical, electrochemical and properties was supported by density functional theory studies. The synthesized molecules were applied in dye-sensitized solar cells as sensitizers and cosensitizers with commercial N719. The thickness and surface morphology of prepared photoanodes was studied using optical, scanning electron and atomic force microscopes. Due to the utilization of benzo[h]quinolin-10-ol derivatives as co-sensitizers, the better photovoltaic performance of fabricated devices compared to a reference cell based on a neat N719 was demonstrated. Additionally, the effect of co-adsorbent chemical structure (cholic acid, deoxycholic acid and chenodeoxycholic acid) on DSSC efficiency was explained based on the density functional theory

Lipid-coated ruthenium dendrimer conjugated with doxorubicin in anti-cancer drug delivery: Introducing protocols

One of the major limitations for the treatment of many diseases is an inability of drugs to cross the cell membrane barrier. Different kinds of carriers are being investigated to improve drug bioavailability. Among them, lipid or polymer-based systems are of special interest due to their biocompatibility. In our study, we combined dendritic and liposomal carriers and analysed the biochemical and biophysical properties of these formulations. Two preparation methods of Liposomal Locked-in Dendrimers (LLDs) systems have been established and compared. Carbosilane ruthenium metallodendrimer was complexed with an anti-cancer drug (doxorubicin) and locked in a liposomal structure, using both techniques. The LLDs systems formed by hydrophilic locking had more efficient transfection profiles and interacted with the erythrocyte membrane better than systems using the hydrophobic method. The results indicate these systems have improved transfection properties when compared to noncomplexed components. The coating of dendrimers with lipids significantly reduced their hemotoxicity and cytotoxicity. The nanometric size, low polydispersity index and reduced positive zeta potential of such complexes made them attractive for future application in drug delivery. The formulations prepared by the hydrophobic locking protocol were not effective and will not be considered furthermore as prospective drug delivery systems. In contrast, the formulations formed by the hydrophilic loading method have shown promising results where the cytotoxicity of LLD systems with doxorubicin was more effective against cancer than normal cells

In-depth studies of ground- and excited-state properties of Re(I) carbonyl complexes bearing 2,2′:6′,2′′-terpyridine and 2,6-bis(pyrazin-2-yl)pyridine coupled with π‑conjugated aryl chromophores

In the current work, comprehensive photophysical and electrochemical studies were performed for eight rhenium(I) complexes incorporating 2,2′:6′,2″-terpyridine (terpy) and 2,6-bis(pyrazin-2-yl)pyridine (dppy) with appended 1-naphthyl-, 2-naphthyl-, 9-phenanthrenyl, and 1-pyrenyl groups. Naphthyl and phenanthrenyl substituents marginally affected the energy of the MLCT absorption and emission bands, signaling a weak electronic coupling of the appended aryl group with the Re(I) center. The triplet MLCT state in these complexes is so low lying relative to the triplet 3ILaryl that the thermal population of the triplet excited state delocalized on the organic chromophore is ineffective. The attachment of the electron-rich pyrenyl group resulted in a noticeable red shift and a significant increase in molar absorption coefficients of the lowest energy absorption of the resulting Re(I) complexes due to the contribution of intraligand charge-transfer (ILCT) transitions occurring from the pyrenyl substituent to the terpy/dppy core. At 77 K, the excited states of [ReCl(CO)3(Ln-κ2N)] with 1-pyrenyl-functionalized ligands were found to have predominant 3ILpyrene/3ILCTpyrene→terpy character. The 3IL/3ILCT nature of the lowest energy excited state of [ReCl(CO)3(4′-(1-pyrenyl)-terpy-κ2N)] was also evidenced by nanosecond transient absorption and time-resolved emission spectroscopy. Enhanced room-temperature emission lifetimes of the complexes [ReCl(CO)3(Ln-κ2N)] with 1-pyrenyl-substituted ligands are indicative of the thermal activation between 3MLCT and 3IL/3ILCT excited states. Deactivation pathways occurring upon light excitation in [ReCl(CO)3(4′-(1-naphthyl)-terpy-κ2N)] and [ReCl(CO)3(4′-(1-pyrenyl)-terpy-κ2N)] were determined by femtosecond transient absorption studies

Pluralizm prawny. Tradycja, transformacje, wyzwania, 510 s.

Książka poświęcone tradycji, współczesności i prognozowanej przyszłości zjawiska pluralizmu prawnego. Fenomen ten został w ukazany z różnych punktów widzenia - towarzyszących mu prądów ideowych, uwarunkowań politycznych, ekonomicznych, a także zmieniającego się technicznego otoczenia życia społeczeństw, szczególnie nowych systemów masowej, horyzontalnej i wertykalnej komunikacji