ABSTRACT
Singlet oxygen quantum yields (ΦΔ) of different perylene diimides (PDIs) containing phenyl (PDI-Ph), pyrene (PDI-Pyr), and indole (PDI-In) units in bay positions of the ring were determined using 1,3-diphenylisobenzofuran (DPBF) method in toluene/methanol (99:1) system. Pyrene-substituted PDI were the most efficient singlet oxygen generator among the investigated photosensitizers with a quantum yield of Φ Δ = 0.93 in toluene/methanol. Additionally, their binding affinities to G-quadruplex DNA structure were investigated by steady-state measurements. There were marked red shifts of absorbance bands for PDI-Pyr/DNA strand complexes with respect to the absorption maxima of DNA-free solution of PDI-Pyr in phosphate buffer at pH 6.
Subject(s)
DNA/chemistry , G-Quadruplexes , Imides/chemistry , Perylene/analogs & derivatives , Photosensitizing Agents/chemistry , Quantum Theory , Singlet Oxygen/chemistry , DNA/metabolism , Imides/metabolism , Molecular Structure , Perylene/chemistry , Perylene/metabolism , Photosensitizing Agents/metabolism , Singlet Oxygen/metabolismABSTRACT
A perylene diimide type small molecule (BI-PDI) has been synthesized through Suzuki coupling reaction between N,N'-bis(2,6-diisopropylphenyl)-1,7-dibromoperylene-3,4,9,10-tetracarboxylic diimide and 2-(2-hydroxyphenyl)-7-phenyl-1H-benzimidazole-4-boronic acid. BI-PDI small molecule has showed an absorption band between 350 and 750 nm on thin films. HOMO and LUMO energy levels of BI-PDI dye have been calculated to be about -5.92 eV and -3.82 eV, respectively. Solution-processed bulk heterojunction (BHJ) solar cells have been constructed using BI-PDI as donor and [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) as acceptor or poly(3-hexylthiophene) (P3HT) as donor and BI-PDI as acceptor. The external quantum efficiencies (EQE) of the devices cover the most of the visible region between 400 and 700 nm for both configurations. Photovoltaic performances of BI-PDI-based organic solar cells are limited by the aggregation tendency of PDI structure and poor hole/electron mobilities of the active layer.
Subject(s)
Benzimidazoles/chemistry , Imides/chemistry , Light , Perylene/analogs & derivatives , Solar Energy , Perylene/chemistryABSTRACT
Sahara desert sand (SaDeS) was employed as a mineral sorbent for retaining organic dyes from aqueous solutions. Natural sand has demonstrated a strong affinity for organic dyes but significantly lost its adsorption capacity when it was washed with water. Therefore, characterization of both natural and water washed sand was performed by XRD, BET, SEM and FTIR techniques. It was found that water-soluble kyanite, which is detected in natural sand, is the dominant factor affecting adsorbance of cationic dyes. The sand adsorbs over 75% of cationic dyes but less than 21% for anionic ones. Among the dyes studied, Methylene Blue (MB) demonstrated the strongest affinity for Sahara desert sand (Q(e)=11.98 mg/g, for initial dye solution concentration 3.5 x 10(-5)mol/L). The effects of initial dye concentration, the amount of the adsorbent, the temperature and the pH of the solution on adsorption capacity were tested by using Methylene Blue as model dye. Pseudo-first-order, pseudo-second-order and intraparticle diffusion models were applied. It was concluded that adsorption of Methylene Blue on Sahara desert sand followed pseudo-second order kinetics. Gibbs free energy, enthalpy change and entropy change were calculated and found -6411 J/mol, -30360 J/mol and -76.58 J/mol K, respectively. These values indicate that the adsorption is an exothermic process and has a spontaneous nature at low temperatures.
Subject(s)
Coloring Agents/isolation & purification , Silicon Dioxide/chemistry , Water Purification/methods , Adsorption , Africa, Northern , Aluminum Silicates , Cations , Diffusion , Kinetics , Methylene Blue/isolation & purification , Thermodynamics , Water Pollutants/isolation & purificationABSTRACT
A novel distyryl-substituted boradiazaindacene (BODIPY) dye displays interesting properties as a sensitizer in DSSC systems, opening the way to further exploration of structure-efficiency correlation within this class of dyes.
ABSTRACT
New [Ru(L1)(dcbpy)(NCS)2] complex was synthesized in a one-pot reaction starting from [RuCl2(p-cymene)]2, where the ligands (dcbpy=4,4'-dicarboxy-2,2'-bipyridine, L1=dipyrido[3,2-a:2',3'-c]phenazine-11-ylcarbonyl)-sodium) are introduced sequentially. The resulting complex was characterized by IR, NMR, and elemental analysis. The complex was labeled with I-131. Biodistribution study of the complex was carried out using 131I-labeled [Ru(L1)(dcbpy)(NCS)2] complex. The biodistribution study performed with albino Wistar male rats has shown that the complex has high uptake in the lung, small intestine, fat, and spleen.
