A5022830937- Porphyrin and Phthalocyanine Chemistry
- Photochemistry and Electron Transfer Studies
- Fullerene Chemistry and Applications
- Molecular Junctions and Nanostructures
- Luminescence and Fluorescent Materials
- Organic Electronics and Photovoltaics
- Quantum Dots Synthesis And Properties
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Photosynthetic Processes and Mechanisms
- Perovskite Materials and Applications
- Advanced Photocatalysis Techniques
- TiO2 Photocatalysis and Solar Cells
- Spectroscopy and Quantum Chemical Studies
- Analytical Chemistry and Sensors
- Photoreceptor and optogenetics research
- Conducting polymers and applications
- Graphene research and applications
- Synthesis and Properties of Aromatic Compounds
- Electrochemical Analysis and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Molecular Sensors and Ion Detection
- Chalcogenide Semiconductor Thin Films
- Radical Photochemical Reactions
- Carbon Nanotubes in Composites
Tampere University
2016-2025
Bioengineering Center
2019
Universidad Autónoma de Madrid
2018
Kyoto University
2003-2015
Tampere University of Applied Sciences
2008-2015
The University of Tokyo
2005-2015
Kobe University
2015
University of Warsaw
2015
Polish Academy of Sciences
2015
Institute of Organic Chemistry
2015
We have successfully achieved the electron-transfer (ET) state of 9-mesityl-10-methylacridinium ion, produced by a single step photoinduced electron transfer, which has much longer lifetime (e.g., 2 h at 203 K) and higher energy (2.37 eV) than that natural system without loss due to multistep processes.
Both charge-transfer absorption and emission have been observed in porphyrin-linked fullerene where the C60 moiety is closely located on porphyrin plane. Electron-transfer parameters including reorganization energies, free energy changes, electronic coupling matrix elements were determined by analyzing benzene. The estimated as 0.23 ± 0.11 eV, which smallest value among inter- intramolecular donor−acceptor systems ever reported comparable to ones for primary charge separation photosynthetic...
Novel molecular electron donor−acceptor (DA) dyads, composed of a phytochlorin donor and [60]fullerene acceptor, have been photochemically characterized. In these pyrrolidine spacer group links the chlorin C60 moieties covalently, forming rigid dyad with short almost constant D−A distance. The photochemical behavior metal-free dyads corresponding Zn complexes was studied by means fluorescence absorption spectroscopies femto- picosecond time resolutions in polar benzonitrile nonpolar toluene...
Boron dipyrromethene (BODIPY), which is commonly used as an energy absorbing and transferring antenna molecule, has been modified to contain electron donor moiety, 8-(2,4,5-trimethoxyphenyl)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (MEOPHBDP). The photoinduced transfer from a 2,4,5-trimethoxyphenyl moiety BODIPY of MEOPHBDP in acetonitrile was observed by femtosecond laser flash photolysis measurements. lifetime the charge-separated state 59 ps at 298 K. dye-sensitized...
We have prepared meso-bis(diarylamino)-substituted porphyrins (cis-ZnP and trans-ZnP), meso-diarylamino-substituted porphyrin (mono-ZnP), reference without the meso-diarylamino group (ZnP) to evaluate effects of substituent number position diarylamino groups on optical, electrochemical, photovoltaic properties for first time. With increasing groups, light-harvesting were improved in visible region. The optical electrochemical HOMO−LUMO gaps parallel those estimated by DFT calculations....
Intramolecular singlet fission (ISF) is a promising photophysical process to construct more efficient light energy conversion systems as one excited state converts into two triplet states. Herein we synthesized and evaluated bent-shaped pentacene dimers prototype of ISF reveal intrinsic characters states (e.g., lifetimes states). In this study, meta-phenylene-bridged TIPS-pentacene dimer (PcD-3Ph) 2,2′-bipheynyl bridged (PcD-Biph) were newly dimers. the steady-state spectroscopy, absorption...
Phytochromes are light sensor proteins found in plants, bacteria, and fungi. They function by converting a photon absorption event into conformational signal that propagates from the chromophore through entire protein. However, structure of photoactivated state changes lead to it not known. We report time-resolved x-ray scattering full-length phytochrome Deinococcus radiodurans on micro- millisecond time scales. identify twist histidine kinase output domains with respect chromophore-binding...
Abstract The unprecedented dependence of final charge separation efficiency as a function donor–acceptor interaction in covalently‐linked molecules with rectilinear rigid oligo‐ p ‐xylene bridge has been observed. Optimization the electronic coupling remarkably inhibits undesirable rapid decay singlet charge‐separated state to ground state, yielding long‐lived, triplet circa 100 % efficiency. This finding is extremely useful for rational design artificial photosynthesis and organic...
Colloidal lead-free perovskite nanocrystals have recently received extensive attention because of their facile synthesis, the outstanding size-tunable optoelectronic properties, and less or no toxicity in commercial applications. Tin (Sn) has so far led to most efficient solar cells, yet showing highly unstable characteristics ambient conditions. Here, we propose synthesis all-inorganic mixture Sn-Ge nanocrystals, demonstrating role Ge2+ stabilizing Sn2+ cation while enhancing optical...
Pentacene dimers bridged by a phenylene at ortho and meta positions [denoted as o-(Pc)2 m-(Pc)2] were synthesized to examine intramolecular orientation-dependent multiexciton dynamics, especially focusing on singlet fission (SF) recombination from correlated triplet pairs [(TT)]. Absorption electrochemical measurements indicated strong couplings of relative m-(Pc)2. Femtosecond nanosecond TA successfully demonstrated efficient SF in both dimers. In contrast, the dissociation process (TT)...
Amorphous titania (am.-TiO2) has gained wide interest in the field of photocatalysis, thanks to exceptional disorder-mediated optical and electrical properties compared crystalline TiO2. Here, we study effects intrinsic Ti3+ nitrogen defects am.-TiO2 thin films via atomic layer deposition (ALD) chemistry tetrakis(dimethylamido)titanium(IV) (TDMAT) H2O precursors at growth temperatures 100–200 °C. X-ray photoelectron spectroscopy (XPS) computational analysis allow us identify structural...
Graphitic carbon nitride (g-CN) is a transition metal free semiconductor that mediates variety of photocatalytic reactions. Although photoinduced electron transfer often postulated in the mechanism, proton-coupled (PCET) more favorable pathway for substrates possessing X-H bonds. Upon excitation an (sp2 )N-rich structure g-CN with visible light, it behaves as photobase-it undergoes reductive quenching accompanied by abstraction proton from substrate. The results modeling allowed us to...
Abstract Hydrogen peroxide (H 2 O ) is a crucial chemical used in numerous industrial applications, yet its manufacturing relies on the energy‐demanding anthraquinone process. Solar‐driven synthesis of H gaining traction as promising research area, providing sustainable method for production. Herein, controllable activation n → π* electronic transition presented to boost photocatalytic evolution ionic carbon nitrides. This enhancement achieved through simultaneous introduction structural...
The ultrafast photodynamics of porphyrin−fullerene dyads in which the distance between porphyrin and C60 moieties is varied systematically at close proximity has been examined using fluorescence up-conversion pump−probe transient absorption techniques with time resolutions ca. 100 fs. are MP-D-C60 (M = Zn 2H) moiety directly connected ring meso position MP-O-C60, MP-M-C60, MP-P-C60 linked through benzene ortho, meta, para positions, respectively. charge transfer (CT) bands observed for...
The photoinduced electron transfer in differently linked zinc porphyrin-fullerene dyads and their free-base porphyrin analogues was studied polar nonpolar solvents with femto- to nanosecond absorption emission spectroscopies. A new intermediate state, different from the locally excited (LE) chromophores complete charge-separated (CCS) observed. It identified as an exciplex. exciplex preceded CCS state benzonitrile singlet of fullerene toluene. behavior modeled by using a common kinetic...
A new group of porphyrin−fullerene dyads with an azobenzene linker was synthesized, and the photochemical photophysical properties these materials were investigated using steady-state time-resolved spectroscopic methods. The electrochemical compounds also studied in detail. synthesis involved oxidative heterocoupling free base tris-aryl-p-aminophenyl porphyrins a p-aminophenylacetal, followed by deprotection to give aldehyde, finally Prato 1,3-dipolar azomethineylide cycloaddition C60....
Photoinduced processes in phthalocyanine-functionalized gold nanoparticles (Pc-AuNPs) have been investigated by spectroscopic measurements. The metal-free phthalocyanines used two linkers with thioacetate groups for bonding to the nanoparticle surface, and attachment was achieved using a ligand exchange reaction. absorption spectrum of Pc-AuNPs shows broadening phthalocyanine Q-band absorption, probably due tight packing on surface. For attached phthalocyanines, fluorescence is strongly...
Novel benzo[f]quinoxalino[2,3-β]porphyrin carboxylic acid (ZnBQA) and cyanoquinoxalino[6,7-β]porphyrin (ZnQCA) have been synthesized to evaluate the effects of π-elongation fused position quinoxaline-fused porphyrins on optical, electrochemical, photovoltaic properties. ZnBQA showed a split, red-shifted Soret band relative that quinoxalino[2,3-β]porphyrin (ZnQMA), while Q bands are rather blue-shifted. On other hand, both Q-bands ZnQCA compared those ZnQMA. The optical HOMO−LUMO gaps...
We have prepared a novel push–pull porphyrin with an electron-donating diarylamino group at the meso-position and electron-withdrawing 4-carboxy-2,3,5,6-tetrafluorophenylethynyl anchoring opposite to address substitution effects of fluorine atoms on photovoltaic properties for first time. The fluoro-substituted showed slightly improved light-harvesting when compared reference in solution, due enhancement charge-transfer character. porphyrin-sensitized TiO2 cell exhibited moderate power...
Abstract We have prepared a push–pull porphyrin with an electron‐donating triarylamino group at the β,β ′‐ edge through fused imidazole and electron‐withdrawing carboxyquinoxalino anchoring opposite (ZnPQI) evaluated effects of structure ZnPQI on optical, electrochemical, photovoltaic properties. showed red‐shifted Soret Q bands relative to reference only (ZnPQ), thus demonstrating improved light‐harvesting property ZnPQI. The optical HOMO–LUMO gap was consistent that estimated by DFT...
The kinetics of electron extraction at the transfer layer/perovskite interface strongly affects efficiency a perovskite solar cell. By combining transient absorption and time-resolved photoluminescence spectroscopy, process between FA0.83Cs0.17Pb(I0.83Br0.17)3 TiO2 single crystals with different orientations (100), (110), (111) were probed from subpicosecond to several hundred nanoseconds. It was revealed that band alignment constituents influenced relative process. TiO2(100) showed fastest...
Transient absorption spectroscopy is a powerful technique to study the photoinduced phenomena in wide range of states from solutions solid film samples. It was designed and developed based on changes or that photoexcitation triggers chain reactions with intermediate reaction steps presumably different spectra. However, according general electromagnetic theory, any change properties medium accompanied by refractive properties. Although this index has negligible effect solution measurements,...
Abstract A series of ferrocene(Fc)‐bridged pentacene(Pc)‐dimers [Fc−Ph(2, n )−(Pc) 2 : =number phenylene spacers] were synthesized to examine the tortional motion effect Fc‐terminated linkers on strongly coupled quintet multiexciton ( 5 TT) formation through intramolecular singlet fission (ISF). Fc−Ph(2,4)−(Pc) has a relatively small electronic coupling and large conformational flexibility according spectroscopic theoretical analyses. exhibits high‐yield TT together with quantitative 1...