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In recent years, tridentate nitrogen donor ligands have played a vital role in inorganic chemistry. The ease of synthesis, readily modifiable structure and high stability of 1,3-bis(2-pyridylimino)isoindole (BPIs) compounds make them suitable candidates for many potential applications. In this study, a 1,3-bis(2-pyridylimino)isoindoline derivative bearing a naphthoxy unit and its palladium complex (PdBPI) were synthesized and characterized by single crystal X-ray diffraction, NMR, FT-IR, UV–Vis, and mass spectroscopic methods. The BPI- or PdBPI-modified pencil graphite electrodes were clarified via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), EDX, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The efficiency of these substances in a vanadium redox flow battery (VRB) system was investigated for the first time. The behaviors of the BPI-modified carbon felt electrode (BPI-CF) and PdBPI-modified carbon felt electrode (PdBPI-CF) were investigated in the redox flow battery (RFB) applications. These modified electrodes were obtained by the electrodeposition method. The respective charge potentials of BPI-CF and PdBPI-CF reached 1.63 V and 1.88 V, respectively. The discharge capacity maxima obtained were ∼301 mA h (1204 mA h L−1) and ∼303 mA h (1212 mA h L−1) for BPI-CF and PdBPI-CF at the VRB system under a charge current density of 4.0 mA cm−2 and discharge current density of 0.4 mA cm−2, respectively. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) are significant fluorescent materials for energy transfer studies with phthalocyanines (Pcs) and phthalocyanine (Pc)‐like biomolecules (such as chlorophylls). Carbon‐based QDs, especially, have been used in numerous studies concerning energy transfer with chlorophylls, but the numbers of studies concerning energy transfer between phthalocyanines and carbon‐based QDs are limited. In this study, peripherally, hydroxythioethyl terminal group substituted metal‐free phthalocyanine (H2Pc) and zinc phthalocyanine (ZnPc) were noncovalently (electrostatic and/or π–π interaction) attached to carbon QDs containing boron and nitrogen to form QD‐Pc nanoconjugates. The QD‐Pc conjugates were characterized using different spectroscopic techniques (Fourier transform infrared spectroscopy and transmission electron microscopy). The absorption and fluorescence properties of QD‐Pc structures in solution were studied. It was found that the quantum yields of the QDs slightly decreased from 30% to 25% upon doping the QDs with heteroatoms B and N. Förster resonance energy transfer efficiency was calculated as 33% for BCN‐QD/ZnPc. For the other conjugates, almost no energy transfer from QDs to Pc cores was observed. It was shown that the energy transfer between QDs to Pc cores was completely different from the energy transfer between QDs and photosynthetic pigments, and therefore we concluded that heteroatom doping in the QD structure and the existence of zinc metal in the phthalocyanine structure is obligatory for an efficient energy transfer. [ABSTRACT FROM AUTHOR]

The synthesis and biological properties of tetra-substituted zinc and cobalt phthalocyanines bearing ethynylpy-ridine units on the periphery and their quaternized derivatives have been reported. The binding of quaternized ZnPc and CoPc (Q-ZnPc and Q-CoPc) with calf thymus DNA was investigated by UV-Vis spectrophotometric methods and thermodynamics. The mixtures of Q-ZnPc or Q-CoPc and DNA solutions were used to determine the change in the thermal melting temperature of DNA with the thermal denaturation profile. Thermodynamic parameters that show the spontaneity of the reactions between DNA and the quaternized phthalocyanines were investigated. Kb binding constants at a degree of 105 and 106 for Q-ZnPc and Q-CoPc, respectively, showed that the phthalocyanines bound to DNA fragments efficiently and thermodynamic data proved that the binding process was spontaneous and entropy-driven. The interactions between Q-ZnPc and Q-CoPc and DNA in an aqueous environment corresponded to electrostatic attractions and nonspecific binding. [ABSTRACT FROM AUTHOR]

A supramolecular cobalt phthalocyanine ( CoPc ) bearing four redox active cobaloxime ( CoDMG ) substituents (( CoDMG ) 4 - CoPc ) was synthesized and electrochemically characterized in order to determine its functionalities for practical usages as effective electrocatalysts. Voltammetric analyses of CoDMG , CoPc , and ( CoDMG ) 4 - CoPc indicated redox activity of each compounds and supported substitution of CoPc with CoDMG . ( CoDMG ) 4 - CoPc showed three CoPc based reduction processes and two CoDMG based reduction processes. While CoDMG showed two reduction and one oxidation processes, CoPc illustrated three reduction and two oxidation processes. Binding of CoDMG to CoPc increased the reduction processes to five. Multi-electron and metal and/or ring based redox processes showed worthy of the ( CoDMG ) 4 - CoPc for using as an electrocatalyst. Shifting of the proton reduction reaction toward the positive potentials indicated electrocatalytic activities of the complexes for the hydrogen evolution reaction ( HER ). Among CoDMG , CoPc , and ( CoDMG ) 4 - CoPc , modified glassy carbon electrode with ( CoDMG ) 4 - CoPc illustrated the highest electrocatalytic activity and it decreased the over-potential of the bare electrode about 360 mV and increased the current density of the electrode about 10-fold. [ABSTRACT FROM AUTHOR]

In recent years, tridentate nitrogen donor ligands have played a vital role in inorganic chemistry. The ease of synthesis, readily modifiable structure and high stability of 1,3-bis(2-pyridylimino)isoindole (BPIs) compounds make them suitable candidates for many potential applications. In this study, a 1,3-bis(2-pyridylimino)isoindoline derivative bearing a naphthoxy unit and its palladium complex (PdBPI) were synthesized and characterized by single crystal X-ray diffraction, NMR, FT-IR, UV-Vis, and mass spectroscopic methods. The BPI- or PdBPI-modified pencil graphite electrodes were clarified via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), EDX, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The efficiency of these substances in a vanadium redox flow battery (VRB) system was investigated for the first time. The behaviors of the BPI-modified carbon felt electrode (BPI-CF) and PdBPI-modified carbon felt electrode (PdBPI-CF) were investigated in the redox flow battery (RFB) applications. These modified electrodes were obtained by the electrodeposition method. The respective charge potentials of BPI-CF and PdBPI-CF reached 1.63 V and 1.88 V, respectively. The discharge capacity maxima obtained were ∼301 mA h (1204 mA h L -1 ) and ∼303 mA h (1212 mA h L -1 ) for BPI-CF and PdBPI-CF at the VRB system under a charge current density of 4.0 mA cm -2 and discharge current density of 0.4 mA cm -2 , respectively.