Vladimir I Chukharev

Belgorod National Research University · Stary Oskol Branch

A photoinduced interlayer charge separation in bilayered molecular film, constructed by the Langmuir–Blodgett technique, was demonstrated. The lifetime of the primary charge separated state in a monolayer of porphyrin–fullerene dyad, P–F, was found to be in a microsecond time domain, and was increased due to the secondary electron transfer from pol...

Thin organic films were deposited on silicon oxide surfaces with golden interdigitated electrodes (interelectrode gap was 2 micro m), and the film resistivities were measured in dark and under white light illumination. The compounds selected for the measurements include molecules widely used in solar cell applications, such as polythiophene (PHT),...

An approach to the renewal of the intellectual value laws is proposed, taking into account the super dynamism of the modern world and the latest technological capabilities. We formulate the ideal final result of the update and justify a refusal to recognize the intellectual value as an object for ownership. We propose basic laws, ways of smooth put...

Phytochromes are light sensor proteins found in plants, bacteria, and fungi. They function by converting a photon absorption event into a conformational signal that propagates from the chromophore through the entire protein. However, the structure of the photoactivated state and the conformational changes that lead to it are not known. We report ti...

Photoinduced intra- and interlayer electron transfer (ET) of doubly bridged donor-acceptor molecule, porphyrin-fullerene dyad (PF), was studied in single- and multi-layered Langmuir-Schäfer (LS) films and in LS films, where PF and an efficient electron donating polymer polyhexyltiophene (PHT) formed a bilayer PHT/PF and multi-layered PHT/PF structu...

A Sn (IV)tetraphenylporphyrin (T) has been functionalized with a β-vinyl pyrene (P) and the photophysical properties of the formed dyad (T-P) with its corresponding precursors were studied in three solvents with different polarities using steady-state and time-resolved measurements in ps and fs timescales. When the pyrene moiety is excited at λ ex...

A series of tailored fulleropyrrolidine derivatives with thiophene substituents was synthesized and studied as electron acceptor materials in inverted organic bulk heterojunction (BHJ) solar cells. The study concentrated on seeking correlation between the molecular structure of the acceptor and its capability to form a photovoltaic BHJ film with th...

http://nordic2014.ftmc.lt/media/BookofAbstracts.pdf Bacterial phytochromes are optically sensitive proteins. The dynamic changes during the photoswitching between signalling and resting states take place in many different time scales, from femtoseconds to seconds. Detecting these changes in real time requires a combination of several spectroscopic...

Electron-transfer characteristics of 1,7-dipyrrolidinyl-substituted perylenediimide-fullerene (PyPDI-C60) dyad were studied in solid films by an ultrafast transient absorption technique. The research was further expanded to study a poly(3-hexylthiophene) (P3HT):PyPDI-C60 blend to reveal the charge-transfer processes that take place in bulk heteroju...

The effect of intermolecular proton transfer on the spectral properties of levofloxacin in the ground and excited electronic states was studied. The preferred direction of possible protolytic reactions induced by UV irradiation in this compound was studied. It was found that the proton transfer processes have a considerable effect on the capability...

5-(Diphenylphosphanyl)-10,15,20-triarylporphyrins (meso-phosphanylporphyrins) underwent complexations with palladium(II) and platinum(II) salts to afford phosphapalladacycle- and phosphaplatinacycle-fused coplanar porphyrin dimers, respectively, via regioselective peripheral β-C-H activation of the meso-phosphanylporphyrin ligands. The optical and...

Chemically converted graphene (CCG) covalently linked with porphyrins has been prepared by a Suzuki coupling reaction between iodophenyl-functionalized CCG and porphyrin boronic ester. The covalently linked CCG-porphyrin composite was designed to possess a short, rigid phenylene spacer between the porphyrin and the CCG. The composite material forme...

DOI:10.1134/S1070363212020247. There is an English translation in 'Russian Journal of General Chemistry'.

The nalidixic acid transient spectra were analyzed and the scheme of photo-conversion of the acid was suggested. At a large delay of laser pulses the transient absorption spectra contain the bands due to the dissociation of the products of the cation- and anion-radical photodecomposition in the micro- and millisecond range. By quantum-chemical calc...

Novel nanohybrids of single-walled carbon nanotubes (SWNTs) encapsulating C60 or C70 with poly(3-hexylthiophene) (P3HT) have been prepared and their photophysics and photoelectrochemical properties are studied in detail for the first time. Strong π–π interaction between the SWNT sidewalls and P3HT afforded successful dissolution of the so-called fu...

Fullerene-encapsulating single-walled carbon nanotubes (C(60)@SWNT) linked with porphyrins by a short bridge have been prepared for the first time. Steady state and time-resolved spectroscopies demonstrated the initial formation of an exciplex state, followed by a charge-separated state.

The organization of π-π stacking perylenediimide (PDI) derivative, PDI12, was studied in solution and in thin films. Films were prepared with the Langmuir-Schaeffer (LS) method and characterized by means of AFM, optical profilometry, steady-state absorption, emission, fluorescence lifetime, and transient photovoltage measurements. The columnar aggr...

Photoinduced intra- and intermolecular electron transfer (ET) in thin films of porphyrin-fullerene dyad (P-F) and perylenetetracarboxidiimide (PTCDI) was studied by means of photoelectrical and spectroscopic methods. Films consisting of smooth 100 mol% layers of P-F and PTCDI were prepared by the Langmuir-Schäfer (LS) technique and thermal evaporat...

Multistage electron transfer in a film system consisting of a hole-transporting layer (HTL), donor-acceptor pair (D-A), and an electron-transporting layer (ETL) was studied by photovoltage and flash-photolysis techniques. Poly(3-hexylthiophene) (PHT) was used as the HTL, while a symmetric porphyrin-fullerene dyad (P-F) and perylenetetracarboxidiimi...

The capability of Violanthrone-79 (V-79) and N,N′-bis(2,5-di-tert-butylphenyl)-3,4:9,l0-perylenebis(dicarboximide) (PDI) to act as electron acceptors, with respect to poly(3-hexylthiophene) (PHT) and to the photoinduced fullerene anion of porphyrin-fullerene (P-F) dyad, was demonstrated in Langmuir-Blodgett (LB) films by the time-resolved Maxwell d...

In the three-layer Langmuir-Schaefer films consisting of a monolayer of donor-acceptor phtalocyanine-fullerene dyad molecules (Bu 3ProM 2F) and two layers of poly(3-hexylthiophene) (PHT), placed into an electrochemical cell, the electric current resulted from optical excitation of sampleswas measured with no external voltage source. Samples were ex...

A double-bridged phthalocyanine–fullerene dyad (H2 Pc–C60 ee) was used as photo-active intramolecular donor–acceptor system in a layered organic solar cell. In this device, a poly(3-hexylthiophene) (PHT) film was used as electron donor, whereas either C60 or perylene tetracarboxylic diimide (PTCDI) film was selected as electron acceptor. The introd...

Photoinduced interlayer energy and electron transfer from a thiophene derivative, PVT3, to a porphyrin-fullerene dyad, P-F, was demonstrated. The laser flash photolysis method was utilized to characterize photoinduced processes in layered thin films constructed by the Langmuir-Blodgett and spin-coating techniques. Poly(3-hexylthiophene), PHT, was u...

We report the fabrication and characterization of tapered fibers covered with porphyrin monolayer films prepared by Langmuir-Blodgett (LB) deposition method. The studied molecule was 10 mol-% 5,10,15,20- tetrakis(pentafluorophenyl)porphyrin (PFP) entrapped in an octadecylamine (ODA) matrix. PFP molecules, deposited on plane glass surfaces, have rel...

Efficient photoinduced interlayer electron transfer from a phthalocyanine derivative, ZnPH4, to porphyrin cation of a porphyrin–fullerene donor–acceptor dyad was demonstrated by using time-resolved photovoltage technique. Multicomponent thin films with desired layer arrangements were constructed by the Langmuir–Blodgett and spin-coating methods in...

Surface organization and photochemistry of Langmuir–Blodgett (LB) monolayers of 10 mol-% 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin (PFP) in an octadecylamine (ODA) matrix on flat quartz and tapered optical fiber surfaces are studied. Previous investigations of PFP films on flat surfaces had revealed that they exhibit a relatively long fluores...

Layers of poly(3-hexylthiophene), PHT, phenyl vinyl thiophene, PVT3, poly(p-phenylene-2,3′-bis(3,2′-diphenyl)-quinoxaline-7-7′-diyl), PPQ, and covalently linked porphyrin−fullerene donor−acceptor dyad, P−F, were deposited as various multilayer films, which then were used to study photoinduced electron transfer and photocurrent generation. The aim o...

A relatively long lifetime organic solar cell, containing a thin tris-8-hydroxy-quinolato aluminum (Alq3) layer under an Au cathode, is described. Half-lifetime of the cell in the darkness is over 7 weeks and 30% of the initial power conversion efficiency (η) is obtained after 18 weeks. This represents a substantial increase in lifetime compared to...

Photoinduced electron transfer (ET) processes were studied by the time-resolved Maxwell displacement charge (TRMDC) method in bilayer structures consisting of an electron donor-acceptor and conductive polymer monolayers, porphyrin-fullerene dyad and polyhexylthiophene, respectively, both layers prepared by the Langmuir-Blodgett (LB) method. The cha...

A photovoltaic device and a method for production thereof.

A series of porphyrin fullerene dyads covalently connected to each other with two linkers forming a highly symmetric compound with π-stack sandwich-like structure was systematically studied in solutions and in solid self-assembled monolayers by a variety of steady-state and time-resolved methods. The interchromophore interactions of such compounds...

Two porphyrin-fullerene dyads were synthesized to form self-assembled monolayers (SAMs) on indium-tin oxide (ITO) electrode, with either ITO-porphyrin-fullerene or ITO-fullerene-porphyrin orientations. The dyads contain two linkers for connecting the porphyrin and fullerene moieties and enforcing them essentially to similar geometries of the donor-...

The photoinduced electron transfer reaction of porphyrin–fullerene dyads occurs through an intermediate state, previously identified as a preformed intramolecular exciplex, emitting in the near infrared region (NIR). It can also be seen as a weak absorption band in NIR commonly called the charge transfer absorption band. A detailed analysis of the...

Recently synthesized porphyrin−fullerene dyads with two separate linkers form a nearly symmetric complex with π-stack sandwich-like structure. The interchromophore interactions of such complexes can be fine-tuned by varying the linker lengths, which opens an opportunity to control physical and chemical properties of the dyads. Absorption spectrosco...

A new terthiophene-vinylbenzoate compound has been synthesized for applications in molecular optoelectronic devices. The photophysical properties of the compound have been studied in a series of solvents The compound is characterized by a high emission yield (43% in cyclohexane) and a large solvent-dependent Stokes shift (90-120 nm). The shift is a...

The primary step of the photocycle of bacteriorhodopsin was studied by nanosecond laser flash photolysis with a fixed testing wavelength (632.8 nm) and a varied (in the range 532 – 630 nm) excitation wavelength. The approach to saturation of the transient absorption signal associated with the formation of the intermediate K vs. excitation energy de...

When the spectral shift accompanying formation of a photoproduct is small compared with the full width at half-maximum (FWHM) of the reactant absorption band, direct estimation of the extent of phototransformation becomes impossible. In this paper a method is described for calculating quantum yields and the photoproduct spectrum for photo-reversibl...

Three arguments against cooperativity in the photochem. transition of bacteriorhodopsin to intermediate K are presented. (1) The nonexponentiality of percentage- dose dependence in K state formation can be readily explained by exptl. conditions and cannot be used as an argument against the simple photoreaction mechanism; (2) the differential spectr...