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Two novel perylene-based acid dyes were synthesized to produce fluorescent polyamide fabrics. The dyes were made by reacting perylene-3,4,9,10-tetracarboxylic acid dianhydride (PTCA) with sulfanilic acid and 1-amino-8-hydroxy-3,6-naphthalene disulfonic acid (H-acid) in imidazole as a solvent. FTIR, 1HNMR, UV–Vis, elemental analysis, and spectro-luminescence were used to characterize the synthesized dyes. Dyes with approximately similar maximum wavelengths had molar absorption coefficients of 42,996 and 8636 l mol−1 cm−1 in water. The dyes showed a negative solvatochromism effect with changing the polarity of solvents from water to methanol. Also, the sulfanilic acid-based dye had a higher quantum efficiency (φ = 0.79) and stokes shift (1999 cm−1) than the H-acid-based dye in water. The DFT method analyzed the synthesized dyes' HOMO, LUMO, bandgap, dihedral angles, and angle of substitution. Both dyes had the same bandgap and dihedral angles. Substituted sulfanilic acid derivative had more planar structure than H-acid derivative. The synthesized molecules were used to dye polyamide fabrics. Dyeing kinetics were based on pseudo-second-order and Langmuir isotherms. Also, the sulfanilic-acid derivative had more build-up on polyamide fabrics. According to fabric fastness tests, synthetic dyes had excellent washing and rubbing stability but weak to moderate light fastness. Finally, the fluorescent properties of dyed fabrics were obtained. [ABSTRACT FROM AUTHOR]

Developing solid luminescent materials with a unity quantum yield and tunable emission color is promising, although it is still a difficult task. A straightforward heat‐treatment method has been developed to load 3,4,9,10‐perylenetetracarboxylic dianhydride (PTCDA) into the matrix of boric acid (BA) to produce powders with a near‐unity quantum yield and tunable emission color from yellow to green. Our results suggest that the emission of the powders originates from PTCDA, and the tunability of the emission color is caused by the hydrolysis of PTCDA in the alkaline environment. The near‐unity quantum yield is attributed to the BA matrix, which confines PTCDA. In addition, the powder also shows excellent thermal stability that allows its application in light‐emitting diodes. The above results are important for the development of solid‐state luminescent materials for various applications, and also provide a clue for studying the emission properties of luminescent materials. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have attracted significant interest as one of the most emerging photoluminescence (PL) nanomaterials. However, the realization of CDs with dominant near‐infrared (NIR) absorption/emission peaks in aqueous solution remains a great challenge. Herein, CDs with both main NIR absorption bands at 720 nm and NIR emission bands at 745 nm in an aqueous solution are fabricated for the first time by fusing large conjugated perylene derivatives under solvothermal treatment. With post‐surface engineering, the polyethyleneimine modified CDs (PEI‐CDs) exhibit enhanced PL quantum yields (PLQY) up to 8.3% and 18.8% in bovine serum albumin aqueous and DMF solutions, which is the highest PLQY of CDs in NIR region under NIR excitation. Density functional theory calculations support the strategy of fusing large conjugated perylene derivatives to achieve NIR emissions from CDs. Compared to the commercial NIR dye Indocyanine green, PEI‐CDs exhibit excellent photostability and much lower cost. Furthermore, the obtained PEI‐CDs illustrate the advantages of remarkable two‐photon NIR angiography and in vivo NIR fluorescence bioimaging. This work demonstrates a promising strategy of fusing large conjugated molecules for preparing CDs with strong NIR absorption/emission to promote their bioimaging applications. [ABSTRACT FROM AUTHOR]

Abstract Carbon dots (CDs) have attracted significant interest as one of the most emerging photoluminescence (PL) nanomaterials. However, the realization of CDs with dominant near‐infrared (NIR) absorption/emission peaks in aqueous solution remains a great challenge. Herein, CDs with both main NIR absorption bands at 720 nm and NIR emission bands at 745 nm in an aqueous solution are fabricated for the first time by fusing large conjugated perylene derivatives under solvothermal treatment. With post‐surface engineering, the polyethyleneimine modified CDs (PEI‐CDs) exhibit enhanced PL quantum yields (PLQY) up to 8.3% and 18.8% in bovine serum albumin aqueous and DMF solutions, which is the highest PLQY of CDs in NIR region under NIR excitation. Density functional theory calculations support the strategy of fusing large conjugated perylene derivatives to achieve NIR emissions from CDs. Compared to the commercial NIR dye Indocyanine green, PEI‐CDs exhibit excellent photostability and much lower cost. Furthermore, the obtained PEI‐CDs illustrate the advantages of remarkable two‐photon NIR angiography and in vivo NIR fluorescence bioimaging. This work demonstrates a promising strategy of fusing large conjugated molecules for preparing CDs with strong NIR absorption/emission to promote their bioimaging applications.

We study nucleation and multilayer growth of the perylene derivative PTCDI-C8and find a persistent layer-by-layer growth, transformation of island shapes, and an enhancement of molecular diffusivity in upper monolayers (MLs). These findings result from the evaluation of the ML-dependent island densities, obtained by in situ real-time grazing incidence small angle X-ray scattering measurements and simultaneous X-ray growth oscillations. Complementary ex situ atomic force microscopy snapshots of different growth stages agree quantitatively with both X-ray techniques. The rate and temperature-dependent island density is analyzed using different mean-field nucleation models. Both a diffusion limited aggregation and an attachment limited aggregation model yield in the first two MLs the same critical nucleus size i, similar surface diffusion attempt frequencies in the 1019-1020 s-1 range, and a decrease of the diffusion barrier Ed in the 2nd ML by 140 meV. [ABSTRACT FROM AUTHOR]

• Bay-substituted H 2 PDI molecules are designed for multifunctional photocatalysis. • H 2 PDI, 2Br-H 2 PDI and 4CH 3 CH 2 O-H 2 PDI nanostructures change from 1D, 2D to 0D. • 2Br-H 2 PDI and 4CH 3 CH 2 O-H 2 PDI show 11 and 20 times O 2 evolution rate than H 2 PDI. • 2Br-H 2 PDI and 4CH 3 CH 2 O-H 2 PDI show 1.4 and 4 times H 2 O 2 evolution rate than H 2 PDI. • Without sacrificial agent, the H 2 O 2 evolution rate of 273 μM·g−1·h−1 is achieved. Rational design of semiconductor molecule structure is of significant importance for achieving the multifunctional photocatalysis. Herein, three end/bay-substituted perylenediimide (PDI) molecules, including bis(N-carboxymethyl) perylenediimide (H 2 PDI), 1,7-dibromo-substituted H 2 PDI (2Br-H 2 PDI) and 1,6,7,12-tetraether-substituted H 2 PDI (4CH 3 CH 2 O-H 2 PDI), are synthesized for photocatalytic oxygen evolution (POE) and oxygen reduction reaction (ORR). One-dimensional H 2 PDI nanorods, two-dimensional 2Br-H 2 PDI nanosheets, and zero-dimensional 4CH 3 CH 2 O-H 2 PDI nanoparticles are obtained. Under visible light, 4CH 3 CH 2 O-H 2 PDI as photocatalyst (5.31 mmol·g−1·h−1) exhibits the 1.8-times and 20-times POE rate of 2Br-H 2 PDI (2.93 mmol·g−1·h−1) and H 2 PDI (0.26 mmol·g−1·h−1) with AgNO 3 as sacrificial agent. Additionally, the POE rate can be further improved to 9.34 mmol·g−1·h−1 with the Co2+ doping of 4CH 3 CH 2 O-H 2 PDI. With isopropanol as sacrificial agent, the H 2 O 2 evolution rate of 657.4 μM·g−1·h−1 can be also achieved via photocatalytic ORR with 4CH 3 CH 2 O-H 2 PDI as catalyst, which is ∼3 and ∼4 times those of 2Br-H 2 PDI (220.8 μM·g−1·h−1) and H 2 PDI (160.0 μM·g−1·h−1), respectively. Especially, in the O 2 - or air- saturated aqueous solution without sacrificial agent, the H 2 O 2 rate of 273.1 or 112.7 μM·g−1·h−1 can be also achieved. This work provides a promising way to design the PDI-based multifunctional photocatalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Layered semiconductors such as transition metal dichalcogenides (TMDs) offer endless possibilities for designing modern photonic and optoelectronic components. However, their optical engineering is still a challenging task owing to multiple obstacles, including the absence of a rapid, contactless, and the reliable method to obtain their dielectric function as well as to evaluate in situ the changes in optical constants and exciton binding energies. Here, we present an advanced approach based on ellipsometry measurements for retrieval of dielectric functions and the excitonic properties of both monolayer and bulk TMDs. Using this method, we conduct a detailed study of monolayer MoS2 and its bulk crystal in the broad spectral range (290–3300 nm). In the near- and mid-infrared ranges, both configurations appear to have no optical absorption and possess an extremely high dielectric permittivity making them favorable for lossless subwavelength photonics. In addition, the proposed approach opens a possibility to observe a previously unreported peak in the dielectric function of monolayer MoS2 induced by the use of perylene-3,4,9,10-tetracarboxylic acid tetrapotassium salt (PTAS) seeding promoters for MoS2 synthesis and thus enables its applications in chemical and biological sensing. Therefore, this technique as a whole offers a state-of-the-art metrological tool for next-generation TMD-based devices. [ABSTRACT FROM AUTHOR]

The optical, electrochemical, and electronic properties of a perylene derivative, N,N′-bis(5-amino-1,10-phenanthroline)perylene-3,4,9,10-tetracarboxidiimide (pPDIp), have been investigated. The optical properties were investigated by fluorescence and absorption spectroscopies. The effect of solvent polarity on the optical properties showed that the Stokes shift increased with decreasing solvent polarity, from 252 cm−1 in dimethylformamide to 1011 cm−1 in acetone, indicating greater stability of intramolecular charge transfer (ICT) species in nonpolar solvents, which suggests significant changes in interactions with more compared with less polar solvents. The use of pPDIp as a catalyst in direct ethanol fuel cells was also investigated, using cyclic voltammetry and chronoamperometry. The electrochemical data indicated that pPDIp dispersed in Pt/C (Pt/C:pPDIp) can be used as a catalyst in ethanol electrooxidation, showing catalytic activity analogous to that of metal Pt/C-based catalysts. Direct scanning indicated that the peak current density for the 2:1 Pt/C:pPDIp catalyst was higher than that for mixed catalysts. In addition, chronoamperometry data indicated better catalytic activity at 0.6 V for Pt/C:pPDIp-based catalysts. [ABSTRACT FROM AUTHOR]

Antiviral action of various photosensitizers is already summarized in several comprehensive reviews, and various mechanisms have been proposed for it. However, a critical consideration of the matter of the area is complicated, since the exact mechanisms are very difficult to explore and clarify, and most publications are of an empirical and “phenomenological” nature, reporting a dependence of the antiviral action on illumination, or a correlation of activity with the photophysical properties of the substances. Of particular interest is substance-assisted photogeneration of highly reactive singlet oxygen (1O2). The damaging action of 1O2 on the lipids of the viral envelope can probably lead to a loss of the ability of the lipid bilayer of enveloped viruses to fuse with the lipid membrane of the host cell. Thus, lipid bilayer-affine 1O2 photosensitizers have prospects as broad-spectrum antivirals against enveloped viruses. In this short review, we want to point out the main types of antiviral photosensitizers with potential affinity to the lipid bilayer and summarize the data on new compounds over the past three years. Further understanding of the data in the field will spur a targeted search for substances with antiviral activity against enveloped viruses among photosensitizers able to bind to the lipid membranes.

A fluorescent hollow crystal of 9,10-dicyanoanthracene was filled with a perylene diimide derivative with complementary emissive features. The obtained crystal-in-crystal hybrid was used as a multiresponsive optical waveguide, which showed passive and active modes of light transduction and a bandwidth that extends from the visible to the infrared region. [ABSTRACT FROM AUTHOR]

Abstract A commercially available, soluble in chlorinated hydrocarbons perylene derivative, N,N- bis(1-ethylpropyl)-perylene-3,4:9,10-bis(dicarboximide) (PTCDI-C5(3)), was used to construct n -channel organic field effect transistors (OFETs). The transistors had the top-gate-bottom-contacts (TGBC) architecture, with a spin-coated layer of the active material. This material was subsequently coated with Parylene C gate dielectric layer which, together with a silver gate electrode deposited on the top of that layer, provided a protection of the device against the water and oxygen molecules. In order to investigate the effect of the morphology of semiconductor/gate dielectric interface on the device parameters, a series of OFETs with PTCDI-C5(3) layers spin-coated at different spinning rates were prepared. Three chlorinated hydrocarbon solvents with different boiling points were used: chloroform, chlorobenzene and 1,2-dichlorobenzene. The resulting polycrystalline layers of perylene derivative differed with regard to their thickness and to their roughness as well as exhibited different grains size and shape. Surprisingly however, no direct correlation between the transistor parameters and the thickness of the semiconductor layer or the roughness of the semiconductor/dielectric interface was found – in fact the worst performance was recorded for the OFETs with PTCDI-C5(3) layers of the lowest roughness, spin-coated from chloroform. [ABSTRACT FROM AUTHOR]

Abstract Organic thin films are at the forefront of basic studies and applications in the field of physics, chemistry, biochemistry and materials science. For example, the intrinsic supramolecular arrangement, or simply the formation of aggregates may alter the optical and electrical properties, which would impact the potential applications of the material. Here, an attempt is made to correlate the molecular structures of two perylene derivatives, bis butylimido perylene (BuPTCD) and bis phenethylimido perylene (PhPTCD), with their film formation, in particular, the supramolecular arrangement and the photoluminescent properties. Emission spectra show that the PhPTCD has a radiative efficiency (RE) higher than that for BuPTCD when both are in solutions (monomers). Complementary, regarding PVD films, UV–Vis absorption measurements reveal that PhPTCD forms, predominantly, J aggregates, which are responsible for perylene derivative emission. However, BuPTCD PVD films are found to provide higher RE than PhPTCD PVD film. This apparent controversy could be explained considering other features such as crystallinity and molecular organization. The PVD film of BuPTCD is crystalline while PhPTCD PVD film is amorphous; BuPTCD has an edge-on while PhPTCD has a face-on molecular organization in PVD films. Graphical Abstract Unlabelled Image Highlights • PhPTCD has a radiative efficiency higher than that for BuPTCD in solution. • PhPTCD forms, predominantly, J aggregates, which are responsible for its emission. • BuPTCD is found to provide higher radiative efficiency than PhPTCD in PVD film. • BuPTCD has oriented crystalline phase in PVD films, while for PhPTCD it is amorphous. • Both perylene derivative films have a different molecular organization in PVD films. [ABSTRACT FROM AUTHOR]

In this paper, we report a synthesised water soluble perylene derivative, N , N′ -di(2-aspartic acid)-perylene-3,4,9,10-tetracarboxylic diimide (PASP), for highly sensitive and repeatable detection of copper (Cu2+) and aluminium ions (Al3+) and novel logic gate operation. In the presence of metal ions, a dramatic decrease in PASP optical intensity was induced based on the strong interaction between terminal carboxy groups and the metal ions. Detection limits of 0.22 and 0.24 μM were respectively obtained at physiological pH. The signals could be recovered upon the addition of ethylenediaminetetraacetate (EDTA) and P2O74−, which competed for Cu2+ and Al3+ in the PASP-CuII and PASP-AlIII systems and induced their dissociation as secondary sensors for anions. At least four detection cycles were performed with a high recovery efficiency. Based on these phenomena, a novel three-level logic gate (OR-IMP-OR) was performed for smart signal readout with metal ions (Cu2+ and Al3+) and anions (EDTA and P2O74−) as input signals, and the relative change of optical intensity of PASP as output signal. Furthermore, the prepared PASP molecule also responded sensitively to Cu2+ and Al3+ in 10 % diluted serum medium. A water-soluble perylene probe molecule was synthesised for the highly sensitive and reusable detection of metal ions (Cu2+ and Al3+) with a high recovery efficiency. Based on these phenomena, a novel multi-level logic gate (OR-IMP-OR) operation was performed for smart signal readout. [ABSTRACT FROM AUTHOR]

In this paper, some derivatives of perylene bisimides are successfully synthesized and characterized using FTIR, HNMR and XRD techniques. In addition, their UV–Vis–NIR reflectance spectra are investigated. Synthesized pigments were planned to have high structural similarities as all of them were N,N′-diphenyl-3,4,9,10-perylenedicarboximide derivatives. The substituents are selected from two categories including activating groups and deactivating ones. The correlation between substituent electronic properties and NIR features of the synthesized pigments is investigated, while the data of three previously synthesized derivatives are included. The results have revealed interesting approximate correlation between NIR properties and electronic features of the substituents. Electronically activating groups reduce the reflectance values (on white substrate) of the pigments in comparison with nonsubstituted molecule, while deactivating ones increase the reflectance amount. This result can be a starting point for detailed studying of structure–NIR properties correlation in perylene pigments. Crystallinity (%) of the pigments is estimated using XRD patterns, and the probable correlation of this parameter with NIR properties of the pigments is investigated, and no meaningful correlation is detected. All the pigments are NIR-transparent and subsequently are capable to be used as cool pigments. [ABSTRACT FROM AUTHOR]

Perylene and coronene derivatives, as family members of the novel discotic mesogenic species and active n-type organic semiconductor molecules, are of interest as modular building blocks for new supramolecular architectures. To understand the self-assembly behavior of these kinds of organic molecules, we have designed and synthesized two derivatives, coronene bisimide bearing dimethylamino-propyl groups (CB-DAP) at two imide positions and perylene with a N-(dimethylamino-propyl)-pyrrole-2,5-dione group (P-DAPPD) at only one of the bay positions, respectively. Two different kinds of long-ranged ordered self-assembled monolayers (SAMs) on highly oriented pyrolytic graphite (HOPG) have been observed for the two types of molecules by scanning tunneling microscopy (STM) at room temperature. A comparative analysis of the STM image features implies how the number and position of intermolecular hydrogen bonding affect achiral and chiral SAM structures of the discotic molecules on the HOPG. It is the asymmetrical inter-substituent interactions that induce the molecular orientation change and further varied hydrogen bonding positions among the molecules adsorbed on the substrate. Density functional theory (DFT) calculation results reveal the formation mechanism of the two different ordered molecular arrays. The design of an asymmetric substituent structure for functional π-conjugated organic systems opens a new avenue for the construction of two-dimensional chiral supramolecular networks with advanced properties. [ABSTRACT FROM AUTHOR]

Abstract Perylenediimides (PDIs) are among the most promising non-fullerene electron-acceptors for applications in organic photovoltaics (PV), providing a large scope for structural modifications. PDI-based dimers have shown the highest performances in PV devices owing to their characteristic twisted conformations that reduce their tendency to form large aggregates which are detrimental for PV operation. In this work, two fluorene-bridged perylenediimide (PDI) dimers with oligo(ethylene oxide) or alkyl chains anchored to the C9 position of the fluorene unit were synthesized and investigated in solution-processed organic bulk heterojunction (BHJ) photovoltaic cells as electron acceptors. The PDI dimer substituted with oligo(ethylene oxide) chains resulted in improved power conversion efficiencies (in 20%–53%) in solution processed bulk heterojunction (BHJ) cells with two different polymer donors, PTB7 and PffBT4T-2OD. Nevertheless, the replacement of alkyl chains by oligo(ethylene oxide) chains did not significantly affect the geometric characteristics of the PDI dimers and the optical and electrochemical properties were only marginally modified. Increased exciton dissociation and enhanced charge transport derived from a more densely packed π-π stacking in the solid state caused by ethylene oxide groups are pointed out as possible causes for the improved PV performance. The influence of 1,8-diiodooctane as solvent additive in the blend films was also investigated and allowed to further increase the efficiencies of the cells with PTB7. Overall, the results show that the simple replacement of alkyl chains by oligo(ethylene oxide) chains in PDI dimers is an efficient way to improve the PV performance without compromising the optoelectronic properties of the PDI acceptor. Graphical abstract Image 1 Highlights • Two fluorene-bridged perylenediimide (PDI) dimers with ethylene oxide or alkyl chains in the fluorene were synthesized. • The replacement of alkyl chains by ethylene oxide did not alter significantly the optoelectronic properties of the PDIs. • The PDI with oligo(ethylene oxide)s in photovoltaic cells, as acceptor, resulted in more efficient devices. • The effect of 1,8-diiodooctane as solvent additive in cells with the PDIs was investigated. [ABSTRACT FROM AUTHOR]

Abstract A ditopic bridging ligand, N , N ′- bis (pyridine)-1,6,7,12- tetrakis -(4-methoxyphenoxy)perylene diimide (1) was synthesized. Metallosupramolecular self-assembly of 1 with 2,2′:6′,2″-terpyridyl-platinum(II) and/or -palladium(II) complex ions afforded to new triads [(terpy)M(II)-(1)-M(II)(terpy)](NO 3) 4 where, M(II) = Pt(II) (2), and Pd(II) (3), respectively. These isolated triads 2 and 3 and also free ligand 1 were fully characterized by FT-IR, 1H NMR, 13C DEPT NMR, 1H-1H COSY NMR, MALDI TOF and HRMS (MALDI-TOF/TOF-MS) mass techniques and UV/Vis spectroscopy. DFT studies revealed that the molecular structure of 1 is highly distorted and deviated from the planarity by bulky methoxyphenyl groups at bay positions. The calculated HOMO and LUMO are located on the PDI core and phenyl groups, and the band gap was found to be 2.27, 2.23 and 2.24 eV in DMSO for 1 , 2 and 3 , respectively. The calculated UV/Vis spectra are in good agreement with those of experimental results. Electrochemical, in situ spectroelectrochemical and in situ electrocolorimetric measurements in solution suggested that redox processes of the compounds are accompanied by favourable electron transport properties with remarkably narrow HOMO-LUMO gaps and intense light absorption over the visible range. The association of usually reversible and fast electron transfer processes with the net colour changes in solution pointed out the applicability of the compounds as an electrochromic material. The electrochromic performance measurements with the films of the compounds on indium tin oxide glass provided additional support for their usability as a colour changing material in electrochromic devices. Surface morphologies of the films were characterized by scanning electron microscopy (SEM). The metal complexes of 1 , especially the platinum(II) complex (2), behaved as a good neutral and cathodic colouring electrochromic material with fast response time, long-term stability, and long-term write erase efficiency. The photovoltaic performance of the compounds as electron acceptor material was investigated by varying their relative ratio in the bulk heterojunction solar cells. It was found that the photovoltaic conversion efficiency of the devices strongly depends on the blend ratio. The optimized performance for the devices was obtained with the P3HT: PDIs (weight ratio 1.0: 1.5) blended films. For this blend ratio, the device showed a maximum conversion efficiency of 3.91%, 8.17% and 5.18% for 1 , 2 and 3 , respectively. The results obtained reveal that employing 2 as an acceptor material has great potential for the development of highly efficient nonfullerene bulk heterojunction photovoltaic devices. Graphical abstract Image 1 Highlights • Triads consisting of square planar platinum(II)- and palladium(II)-2,2':6′,2″-terpyridyl chromophores were prepared. • These chromophores coordinated to a ditopic twisted bis(pyridine)-perylene diimide. • These hybrid materials behaved as a colouring electrochromic material. • The device showed a maximum photovoltaic conversion efficiency of 8.17% for the platinum-triad. [ABSTRACT FROM AUTHOR]

Abstract A ladder-type π-system PDIPY that bearing perylene diimide and pyrene units have been developed for constructing non-fullerene acceptors. The vinyl bridged PDIPY dimer PDIPY-V and polymer PPDIPY-V have been synthesized via bromonation and Stille coupling recation. PDIPY-V and PPDIPY-V exhibit intense and broad absorption within 400–650 nm that complement the absorption spectra of the narrow bandgap polymeric donors. DFT calculation indicated that PDIPY-V and PPDIPY-V hold highly twisted structure, which prevent the formation of π−π stacking and crystallization in the aggregated states. The grazing-incidence wide-angle X-ray scattering (GIWAXS) and atomic force microscopy (AFM) investigations confirmed the amorphous nature of the pure films and the PDIPY-V / PPDIPY-V :PTB7-Th blend films. The PDIPY-V :PTB7-Th based photovoltaic device showed a poor performance due to the small LUMO offset of donor and acceptor. While the PPDIPY-V :PTB7-Th based device showed a high PCE of 5.20%, indicating the PDIPY derivatives are promising non-fullerene acceptors for polymer solar cells. Highlights • Ring-fused ladder-type non-fullerene acceptors were synthesized. • The highly twisted structure prevent excessive aggregation of the acceptors. • The acceptors covered a broad absorption region from 400 nm to 650 nm. • The non-fullerene solar cells achieved a high PCE of 5.20%. [ABSTRACT FROM AUTHOR]

The green fraction of humic acid (Pg) and the chloroform-extractable green fraction (CEGF) are characteristic soil organic matter (SOM) components. These alkaline solutions are green-colored due to the presence of 4,9-dihydroxyperylene-3,10-quinone (DHPQ) chromophore. While both of which are potential indicators for the effect of land use and paleoclimatic environment in the fields of soil science as well as geochemistry,  CEGF as well as its relationship with Pg in soils are not yet fully documented. In this study, we firstly investigated the chemical properties of soil CEGF fractions by ultraviolet-visible (UV-Vis) and infrared (IR) method. Two CEGF components were separated by sequential liquid-liquid extraction using aqueous ammonium hydroxide (NH4OH) followed by aqueous sodium hydroxide (NaOH). Results showed that the UV-Vis spectral shape of NH4OH-extractable component is very similar to that of DHPQ, except that it is red-shifted. The solubility and UV-Vis spectrum of the NaOH-extractable fraction were completely identical with those of synthesized DHPQ. Their IR spectral shapes were also almost the same. Subsequently, the distribution of CEGF in humic acid (HA), fulvic acid (FA) and humin (HN) from Japanese Andosols and Cambisol was quantitatively evaluated by sequential extraction. Most of CEGF was detected in the HA (60-78%) and HN (22-40%), but not in the FA. While the UV-Vis spectral shape of CEGF extracted from Andosols HAs showed a relatively higher proportion of DHPQ than its derivative, the opposite was observed in Cambisol HA, whose CEGF is similar to that of sclerotium grain (one of the possible origin of CEGF). These results suggest the diversity of CEGF-producing soil fungi. Quantitative data also indicated that 35-49% of Pg consisted of a chloroform-soluble fraction (i.e., CEGF) and the remaining 51-65% of Pg was chloroform-insoluble. Based on these results, we propose that CEGF is composed of DHPQ and DHPQ-derivatives and that CEGF is one of the major fractions of Pg. [ABSTRACT FROM AUTHOR]

Abstract Novel bi-perylene monoimide derivative with permethyl- β -cyclodextrin grafts (BPMI-CD) was synthesized. BPMI-CD exhibited the maximum absorption and emission bands at 540 nm and 625 nm, showed a large Stoles shift of 81 nm with the fluorescence quantum of 30%, and possessed high water-soluble. More interestingly, BPMI-CD showed a thermo-responsive behavior because of self-inclusion effect. BPMI-CD exhibited the LCSTs from 32 ○C to 48.2 ○C under different concentrations, and showed host-guest controlled thermo-responsive behavior with water-soluble porphyrin and mono-6-O-(p-toluenesulfonyl)-permethyl- β -cyclodextrin (PMCD-Ts) as a competitive host molecule. Graphical abstract Novel bi-perylene monoimide derivative with permethyl-β-cyclodextrin grafts (BPMI-CD) was synthesized, which showed a thermo-responsive behavior in oneself and host-guest controlled thermo-responsive behavior. Image 1 Highlights • BPMI-CD exhibited a large Stokes shift. • BPMI-CD showed thermo-responsive behavior because of self-inclusion effect. • BPMI-CD exhibited host-guest controlled thermo-responsive behavior. • BPMI-CD showed inter-molecular FRET process with guest molecule. [ABSTRACT FROM AUTHOR]

Abstract Here, this study presents a simply synthesis proposal for perylene monoimides with traditional wet solution reaction in one step from commercially available perylene dianhydride and the moderate yield has been got. Their dimmer or ethynylene or butadiynylene bridged perylene derivatives were then developed. The work expanded the structural diversity of these dye molecules to a multifunctional class of n-type semiconductor materials. The high LUMO level (−3.83∼-3.96 eV) reduced the energy loss by associating wide bandgap polymer refer to PC 71 BM (−4.04 eV). Using these compounds as non-fullerene electron acceptors constructs the inverted solar cells, the power conversion efficiency is up to 1.45% for wide band gap polymer donor with an ultrathin active layer thickness of 30 nm. Graphical abstract A new synthesis proposal for perylene monoimides with traditional wet solution reaction in one step and derived none-fullerene acceptors. Image 1 Highlights • A new method to synthesis perylene monoimides. • Obtain three alkynyl bridged perylene monoimides dimmers in gram scale. • New non-fullerene electron acceptors. [ABSTRACT FROM AUTHOR]

Abstract All-polymer solar cells (All-PSCs) have attracted a lot of attention in the recent years due to broad absorption spectra, adjustable chemical structures, high morphological stability, better donor-acceptor compatibility and better mechanical durability. This review summarizes the recent development of perylene diimides (PDI)-based electron acceptors used in all-PSCs because these polymers are promising candidates. The photovoltaic performances of non-fullerene polymer acceptors were compared, and the structure-performance relationship was discussed when the same donor material was used. Highlights • Perylene diimides-based (PDI) n-type copolymers are promising electron-acceptor. • D-A alternating copolymers based on PDI is the most promising kind. • Constructing fused-PDI benefit the photovoltaic performance. • Good morphology should be maintained while enhance the electron mobility. [ABSTRACT FROM AUTHOR]

Graphical abstract A three-dimensional graphene/self-assembled perylene imide (rGO/PDI) aerogel composite has been successfully constructed via a simple low-temperature hydrothermal method. The 3D rGO/PDI composite exhibited remarkably superior visible-light photocatalytic performance. The excellent activity is mainly attributed to the more effective separation of electron–hole pairs. Highlights • The self-assembled PDI and graphene are effectively combined via non-covalent π-π interactions. • The close π-π interaction is beneficial for the carrier mobility and separation of electron–hole pairs. • The 3D structure of graphene improves the adsorption capacity of PDI. • The visible-light photocatalytic performance of rGO/PDI was enhanced in static and dynamic catalytic systems. Abstract A three-dimensional (3D) graphene/self-assembled perylene imide (rGO/PDI) aerogel composite has been successfully constructed via a simple low-temperature hydrothermal method in this work. The 3D rGO/PDI composite exhibited superior visible-light photocatalytic performance. The removal rate was respectively 2.46 times and 3.33 times higher than that of PDI in static and dynamic catalytic systems. The satisfactory activity is mainly attributed to the more effective separation of electron–hole pairs. To be specific, the self-assembled PDI nanofibers and graphene are effectively combined via non-covalent π-π interaction. The π-π interaction enhances the long-range π-electrons delocalization and electron coupling effects, which is beneficial for the carrier mobility and the separation of electron–hole pairs. Meanwhile, the three-dimensional structure of graphene provides a fast multidimensional channel for electron transfer and effectively improves the adsorption capacity of PDI due to the large specific surface area. What's more, the rGO/PDI composite exhibits great stability than the pure PDI. Overall, this work provides a new insight into improving the photocatalytic activity of self-assembled organic materials. [ABSTRACT FROM AUTHOR]

To explore highly efficient yellow-green light conversion agents used for agricultural film, six bay-substituted perylene diimides and their polyvinyl chloride doped films (by 0.5% weight addition) were prepared. The maximum absorption and emission peaks of the luminogens-doped polyvinyl chloride films are located at 581–609 nm and 647–667 nm, respectively. More importantly, the fluorescence quantum yields of PTCDA, t-BuOPTCDA and m-MeOPTCDA are up to 0.88, 0.84 and 0.78 in doping film, respectively. The strengthening solar radiation and outdoor exposure to sunlight last 160 min and two months respectively and the emission intensity of m-MeOPTCDA-doped film displays slight changes and 9% fluctuation in turn. Combined transmittance, compatibility, mechanical properties and thermal stability, m-MeOPTCDA is chosen as the best effective light conversion materials. To better understand the optical properties of the luminogens, molecular configuration optimization, electron cloud density distribution and molecular orbital energy levels were completed by theoretical calculation. Further, the double layer coextrusion film containing m-MeOPTCDA and Triphenyl acrylonitrile is succeed in dual band excitation(350 nm and 580 nm)and emission (430 nm and 651 nm), by optimizing the proportion of m-MeOPTCDA and Triphenyl acrylonitrile, the special light conversion films for different crops will be expected. [ABSTRACT FROM AUTHOR]

Abstract Vibrationally resolved absorption and emission (fluorescence) spectra of perylene and its N-derivatives in gas phase and in solution (acetonitrile) were simulated using a time-dependent approach based on correlation functions determined by density functional theory. By systematically varying the number and position of N atoms, it is shown that the presence of nitrogen heteroatoms has a negligible effect on the molecular structure and geometric distortions upon electronic transitions, while spectral properties change: in particular the number of N atoms is important while their position is less decisive. Thus, the N-substitution can be used to fine-tune the optical properties of perylene-based molecules. [ABSTRACT FROM AUTHOR]

This study reports on the synthesis of an indancenodithiophene perylene diimide tetramer via unique direct (hetero)arylation reactivity. The thiophene based core structure is shown to be easily functionalized with four perylene diimides at the four active C–H positions. This new reactivity provides a simple synthetic pathway towards tetrameric perylene diimides which have emerged as one of the best classes of electron acceptors for organic solar cells. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new electron-deficient monomer borominated 1,2,7,8-tetraazaperylene derivative was synthesized. • Three D–A conjugated polymers were synthesized. • These polymers showed tunable electronic structures via the modification of the main chains and side chains. • The polymer PTPAL-DPP has strong light harvesting capability in the NIR regions. Abstract Development of electron-deficient organic semiconducting monomers is the key role in the construction of donor (D)-acceptor (A) conjugated polymers. In this work, a new type of 1,2,7,8-tetraazaperylene derivative 3,9-bis(5-bromo-4-hexylthienyl)-1,2,7,8-tetraazaperylene (Br-TPAL) with two terminal bromine groups, has been efficiently synthesized. Upon transition-metal catalyzed cross-coupling, Br-TPAL was facile to copolymerize with various monomers, to form three donor–acceptor conjugated polymers PTPAL-OBDT , PTPAL-TBDT PTPAL-DPP in high yields. The electronic structures of the resulting polymers enable being finely tuned through changing the building blocks. They exhibited very rich optoelectronic properties, for example, their absorption bands covered the nearly whole visible regions, or even extending to the NIR regions. These promising characters render them highly desirable for high-performance electronic devices. [ABSTRACT FROM AUTHOR]

Introduction: Telomerase is an enzyme which binds to telomeres and increases its length which leads to extension of lifespan of cells. These enzymes are expressed at detectable levels in cancer cells which makes an attractive target for cancer therapy. The G Quadruplex ligands which bind to telomerase with respect to duplex genomic DNA is of special importance. The Perylene di imides are selected, designed and QSAR study has been done, finally from the QSAR results' docking has been done by G4LDB database. To compare and to narrow down the Docking results from G4LDB database, we have chosen AutoDock tool by selecting a target Telomerase protein (PDB ID: 4B18) to analyse the binding affinity of the protein with respect to the Perylene diimides. The best scored compounds will be efficient for designing new molecules as well as for the anti-cancer therapy. Material: G4LDB Database, AutoDock 4.2, Discovery Studio Visualizer 4.1. Methods: The study was to investigate and compare the results from G4LDB database with the AutoDock results for anti cancer activity of Perylene di imides. The results are visualized by Discovery Studio 4.1 Visualizer. Compound 20 and compound 48 shows best ligand interaction with the selected targets from G4LDB database. From the AutoDock results the compounds are docked with the specific Telomerase protein 4B18 and Compound 11 shows good binding energy when compared with the PIPER. Results: Compounds 11, 20 and 48 showed good biological activity also possessing best binding affinity with the target. Discussion: From the QSAR and Docking studies (G4LDB and AutoDock), 3 compounds (11, 20 and 48) showed good biological activity possessing a strong correlation coefficient, endorses that Perylene derivatives are having strong affinity with the targets. Docking has been done from the results of QSAR study, targeting Telomerase protein to study the binding affinity with the target. Conclusions: From the results, the best compounds will be efficient to inhibit telomerase enzyme and these compounds can be used to design new molecules which will be effective for anticancer therapy. [ABSTRACT FROM AUTHOR]

We report studies on polyimide containing tricarbonyl moiety, which derived from the perylene-3,4,9,10-tetracarboxylic dianhydride and 2,6-diaminoanthraquinone compound, as a novel cathode for a lithium battery. The synthesized polyimide have the higher electron affinity and lower ionization potential values compared to the perylene-3,4,9,10-tetracarboxylic dianhydride, resulting in better redox reversibility than perylene-3,4,9,10-tetracarboxylic dianhydride in the lithium-ion battery. The polyimide exhibits remarkable charge-discharge properties with a specific capacity of 128.43 mA h g-1, excellent Coulombic efficiency (100% over 280 cycles) and good rate capability (78% of the capacity at 200 mA g-1 as compared to 20 mA g-1), which results from several combined advantages such as the presence of an additional carbonyl group, a favorable energy level, and improved conductivity. This result implies that electrochemical properties of polyimide with additional carbonyl group can offer new possibilities for the development of efficient all-organic energy storage systems. [ABSTRACT FROM AUTHOR]

An organic p-n bilayer photocatalyst, comprising a perylene derivative (PTCBI, n-type) and cobalt phthalocyanine (CoPc, n-type), is utilized for the oxidative formation of molecular hydrogen (H 2 ) from a borane-ammonia complex (NH 3 BH 3 , AB). The formation of H 2 occurs photocatalytically at the surface of CoPc in the organo-bilayer, along with the reduction of O 2 by a reducing power generated at PTCBI. The mechanism to illustrate the H 2 -formation from AB by the organo-photocatalyst may be different from that of the conventional photocatalysis by inorganic semiconductors. To further understand the mechanism of H 2 -formation, photoelectrochemistry is further investigated using the PTCBI/CoPc bilayer as a photoanode. Considering the resulting faradaic efficiency for H 2 -formation, at least two possible equations have to be suggested: BH 3 OH − (intermediate) + 3OH −  → BO 2 −  + 3/2H 2  + 2H 2 O + 3e − and BH 3 OH − (intermediate) + 2OH −  → BO 2 −  + 2H 2  + H 2 O + 2e − . [ABSTRACT FROM AUTHOR]

A novel non-enzymatic electrochemical sensor for highly sensitive and selective detection of dopamine was developed based on a 3,4,9,10-perylene tetracarboxylic acid functionalized graphene–multiwalled carbon nanotube–gold nanoparticle nanocomposite modified glassy carbon electrode (PTCA-RGO-MWCNTs-Au NPs/GCE). The nanocomposite film was prepared by a facile, eco-friendly and controllable route and its morphology was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopic (EDX) analysis, and X-ray diffraction (XRD) spectroscopy, respectively. Cyclic voltammetry and chronoamperometry were used for evaluating the electrochemical behaviors of the prepared sensor. The DA sensor exhibited excellent electrochemical performance toward DA with a sensitivity as high as 0.124 μA mM−1, a wide linear range of 1–100 μM and a low detection limit of 0.07 μM (S/N = 3). Moreover, it showed good selectivity toward DA without any obvious interference by AA and UA. Furthermore, the prepared DA sensor was applied to detect DA in real samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Perylene derivatives of N,N′-bis(2,6-diisopropylphenyl)-1,6(7)-dibromoperylene-3,4,9,10-tetracarboxylic diimide (DBrPDI) and 1,7-dibromo perylene-3,4,9,10-tetracarboxylic acid butyl ester (DBrPTE) were synthesized, and their structural and optical characterizations were explored. Both DBrPDI and DBrPTE, which were utilized as wavelength converters on a GaN/InGaN based blue LED, were singlet sensitizers and had molar absorptivity constants around 104 Lmol−1cm−1. The blue LED that was used had Commission internationale de l'eclairage (CIE) coordinates of x, y = 0.13, 0.06; power and luminous efficiencies of 2.7 lm/W and 6.6 cd/A @5 mA, respectively. Because the fluorescence quantum yield of DBrPDI was much higher than that of DBrPTE, a meaningful white light efficiency was obtained with the diimide derivative. The use of DBrPDI resulted in white light with CIE coordinates of x, y = 0.34, 0.29 and luminous efficiency of 6.35 cd/A @5 mA, respectively. Using DBrPDI in a resin matrix resulted in more than three orders of magnitude increase in the luminous efficiency value (23.0 cd/A @5 mA) while the CIE coordinates remained the same. Whenever the applied current reached 20 mA, a CRI value of Ra = 90 was obtained. [ABSTRACT FROM AUTHOR]

A novel conjugated microporous polymer based on perylene tetraanhydride bisimide (DP 2 A 2 ) has been synthesized through Sonogashira–Hagihara cross-coupling polymerization of tetrabromo-substituted perylene tetraanhydride bisimide derivative (DPBr 2 ABr 2 ) with 1,4-diethynylbenzene, whose Brunauer–Emmett–Teller (BET) specific surface area is about 378 m 2  g −1 . The fluorescence quenching behaviors of the DP 2 A 2 were investigated. It is found that the DP 2 A 2 shows high sensitivity and selectivity to tracing o-nitrophenol (o-NP) in THF with Ks V constant of 2.00 × 10 4  L mol −1 . The detection limit (LOD) is 1.50 × 10 −9  mol L −1 . The possible sensing mechanism for the luminescent quenching of DP 2 A 2 towards o-NP exciting at 365 nm was considered the donor–acceptor electron transfer mechanism, which is a combined result from both dynamic (collisional) and static quenching. Moreover, the static quenching process is dominant for DP 2 A 2 . [ABSTRACT FROM AUTHOR]

Abstract: The preparation of homo‐ and heterocomplexes composed of the parent perylene diimide (PH) and pyrrolidine‐substituted perylene diimide (PN) in DNA and rapid electron transfer in these complexes, which has been analyzed by steady‐state fluorescence and femtosecond transient absorption measurements, have been demonstrated. The DNA molecules possessing PH and PN were prepared through a recently developed method that involved the reaction of enzymatically generated abasic sites with the amino groups of the perylene diimide molecules, through which these molecules can be incorporated as base surrogates within the DNA base stack. Melting temperature analysis showed that the PH and PN monomers, and their homo‐ and heterodimers, contribute to the stabilization of the DNA duplex, and is comparable to that of natural base pairs. Fluorescence measurements showed that PH in a single‐stranded oligopyrimidine showed a strong fluorescence, whereas the fluorescence of PH was completely quenched upon pairing with PN (PH/PN) through duplex formation. The transient absorption measurements showed that a rapid electron‐transfer reaction in the stacked PH/PN heterodimer occurred on a sub‐picosecond timescale, which allowed highly efficient fluorescence quenching. The PH/PN pair, which served as a fluorophore and quencher, were utilized to design molecular beacon probes with a high signal/noise ratio. The PH/PN pair was also capable of forming a stable, stacked dimer structure and induced rapid electron transfer that could serve as a good signal reporter for fluorescent nucleic acid detection. [ABSTRACT FROM AUTHOR]

The orthogonal- or co-assembly of achiral perylene bisimide (PBI) with chiral gelators can be regulated by solvents. While the coassembly leads to the formation of chiroptical nanofibers through chirality transfer, the orthogonal assemblies could not. Moreover, protonation on the coassembled nanofibers could light up the circularly polarized luminescence (CPL). [ABSTRACT FROM AUTHOR]

Dye Sensitized Solar Cells (DSSCs) are promising optoelectronic devices that use renewable energy and organic or organometallic dyes as light harversters. They exhibit moderate overall efficiencies of power conversion that can be increased by improving the light-harvesting capacity of the organic dyes. Here, we report the synthesis, structural and electronic properties of two novel dyes based on perylene imides PI-1 and PI-2 as well as their application in DSSCs. In our design, design triphenylamine electron donors were linked to perylene-3,4,9,10-tetracarboxylic dianhydride derivative. The new dyes showed a broad absorption spectrum in the visible region as well as a strong push – pull electronic interaction determined computationally. Photovoltaic values for these dyes were not higher than previously reported compounds based on perylenes, with the best photovoltaic performance observed for the DSSCs based on PI-2 , with an overall conversion efficiency of 1.3% under AM 1.5 irradiation (100 mW cm −2 ). Although the electron transport to the TiO 2 surface for PI-1 and PI-2 was not efficient enough to result in a high photovoltaic behavior, our design has afforded dyes exhibiting a more efficient light capture in the visible region. [ABSTRACT FROM AUTHOR]

The π-conjugated molecules, anthracene, pyrene and perylene with stepwise enhanced conjugation, have become a key ingredient in the design of new organic semiconductors for light emission and energy harvesting applications. Here, new biphenyl dissubstituted anthracene, pyrene and perylene derivatives are synthesized and investigated as blue-emitting materials. The designed molecules exhibited typical amplified spontaneous emission (ASE) behavior in solid thin films for the compounds dispersed in the inert polystyrene host at a rather large (5 wt%) chromophore concentration. Theoretical analysis assists in understanding the emission properties and optical gain performance. The calculations reveal enhanced transition density and increased transition dipole moment accompanying by stepwise enhanced molecular conjugation of fluorophore-cores. In addition, enhanced fluorescence quantum yield, significant shortened fluorescence lifetimes and increased radiative decay rate for designed compounds promote the occurrence of ASE behavior compared with anthracene, pyrene and perylene. As well, the vibration analysis show that the intramolecular vibrational modes of researched molecules possessed small Huang-Rhys factors, which thus bring in effective competition between radiative and non-radiative decay process in favor of optical gain. The experimental and theoretical provide evidence that the reported molecules are promising candidates for organic laser applications. [ABSTRACT FROM AUTHOR]

Two novel highly fluorescent hydroxyl-substituted perylene diimides derivatives, N , N -dicyclohexyl-1-hydroxyperylenediimide ( 1 ) 2,9-dicyclohexyl-5,5-dimethyl-12-hydroxy-5,6-dihydropyreno[2,1,10-def:7,8,9-d′e′f′]diisoquinoline-6-oxa-1,3,8,10(2H,9H)-tetraone ( 2 ) were designed and efficiently synthesized through a single aromatic nucleophilic displacement reaction. The physical properties of the as-prepared compounds had been fully studied. Both receptors have shown no affinity for other anions, such as Cl − , Br − , I −, SO 4 − , PF 6 − , H 2 PO 4 − , BF 4 − , AcO − , ClO 4 − (as salt of tetra- n -butylammonia) and ammonium hydroxide. Interestingly, they can be served as colorimetric and fluorescent chemodosimeter for fluoride ion using hydroxyl as binding sites, which was the first report of hydroxyl-modified PDIs based photodetector of fluoride ion. Upon addition of F − anion to compound 2 solution, dramatic color change and fluorescence quenching were observed. Furthermore, the red-shifted maximum absorption wavelength reached 207 nm to the far-red region, which was the maximal spectrum bathochromic-shift of PDIs used in fluoride detection. In addition, the two fluoride sensor can be used under illumination from a laboratory hand-held UV lamp. These results demonstrated that using facile synthetic routes to constructing PDIs molecules with hydroxyl moiety was a useful strategy for designing high performance fluoride recognization. [ABSTRACT FROM AUTHOR]

Three novel perylene derivatives were prepared by introducing two phenyl (biphenyl or naphthyl)-bridging cholesterol units on bay positions and six alkyl chains on imides positions. The influences of different bay-bridging spacers on mesomorphic properties and photophysical properties were investigated. They presented the ordered hexagonal columnar liquid crystalline behaviours, although the large aromatic spacers were bridged on the bay positions. The mesomorphic and photophysical properties could be tuned effectively by the structures of spacers on bay positions. The larger and more rigid aromatic spacer on bay positions resulted in higher phase transition temperatures and stronger fluorescence emission. [ABSTRACT FROM AUTHOR]

Perylene-66 thin films were efficiently prepared at room temperature utilizing thermal evaporation technique (TET). The XRD and FT-IR of the powder and the as-deposited film were examined. A hybrid (organic/inorganic) heterojunction device based on perylene-66 growth onto p-type silicon wafer was characterized by the impedance spectroscopy (IS) method in the frequency range from 100 Hz to 2 MHz and the temperature range from 303 K to 383 K in dark. The Cole–Cole plots show 2 relaxation mechanisms for all temperatures. The maximum barrier height WM value is 0.26 eV. The AC conductivity is found to comply Jonscher's universal power law, and the correlated barrier hopping was observed to be the predominant conduction mechanism for the charge carrier transport. [ABSTRACT FROM AUTHOR]

Abstract: Studies were carried out on the hierarchical self‐assembly versus pathway complexity of N‐annulated perylenes 1–3, which differ only in the nature of the linking groups connecting the perylene core and the side alkoxy chains. Despite the structural similarity, compounds 1 and 2 exhibit noticeable differences in their self‐assembly. Whereas 1 forms an off‐pathway aggregate I that converts over time (or by addition of seeds) into the thermodynamic, on‐pathway product, 2 undergoes a hierarchical process in which the kinetically trapped monomer species does not lead to a kinetically controlled supramolecular growth. Finally, compound 3, which lacks the amide groups, is unable to self‐assemble under identical experimental conditions and highlights the key relevance of the amide groups and their position to govern the self‐assembly pathways. [ABSTRACT FROM AUTHOR]

Three derivatives of perylene diimide, namely N , N ′-ditridecylperylene-3,4,9,10-tetracarboxylic diimide (DT-PDI), N , N ′-dipentylperylene-3,4,9,10-tetracarboxylic diimide (DP-PDI) and N , N′ -bis(1-hexylheptyl)perylene-3,4,9,10-tetracarboxylic diimide (DH-PDI) differ in their side-chain substitution have been examined to study the effect of side-chain substituents on their optical properties and structural morphology. Due to the different side-chain, the self-assembly of these molecules results in totally different optical properties and structural morphologies, as confirmed from the steady-state absorption and fluorescence, time resolved fluorescence, and scanning electron microscopy (SEM) techniques. The collected results confirmed the formation of one-dimensional (1D) nanowires in the case of short linear side chain, chunky aggregates in the case of long linear substituted side chain, and zero-dimensional (0D) nanospheres with the branched substituted side chain. [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cells (DEFCs) are considered a viable alternative power source for both stationary and mobile applications. Obstacles to widespread use of DEFCs include the slow electro-oxidation kinetics of ethanol, which has been countered by employing combinations of noble metals and organic compounds as catalysts, e.g., a platinum alloy and perylene-3,4:9,10-tetracarboxylic acid derivatives (PDIs). This study investigates the performance of a PDI functionalized with 4-amino pyridine (PDI1) and subsequently dispersed in Pt/C (Pt/C/PDI1) and PtSn/C (PtSn/C/PDI1). The performance of these catalysts in ethanol electro-oxidation (EOR) was compared to that of metallic catalysts (PtSn/C and Pt/C). The forward potential scan indicated that the peak current densities (j) on the catalysts Pt/C/PDI1 and PtSn/C/PDI1 were ~ 1.7 and ~ 1.3-fold that of Pt/C and ~ 1.8 and ~ 1.4-fold that of PtSn/C. Concerning ethanol oxidation, this indicates that Pt/C/PDI1 and PtSn/C/PDI1 exhibit better catalytic activity in EOR than Pt/C and PtSn/C do. [ABSTRACT FROM AUTHOR]

The influence of substituents of newly synthesized perylenediimides on their spectral properties and excited state relaxation has been studied by means of steady-state and time-resolved spectroscopy and quantum chemical calculations. Substituents at the perylene core cause broadening and shift of the absorption and fluorescence bands and also reduce the fluorescence quantum yield. Organic 4-tert-butylphenoxy substituents reduce the fluorescence yield by tens of percent by slightly reducing the oscillator strength of the radiative transition and by significantly increasing the non-radiative decay rate. We attribute both changes mainly to the distortion of the planarity of the perylene core. Bromine substituents reduce the fluorescence quantum yield by up to two orders of magnitude by opening an internal conversion channel. [ABSTRACT FROM AUTHOR]

Derivative perylene molecules deposited on Ag(111) and on NaCl(001) ultrathin layers have been investigated using low temperature STM and NC-AFM. When the metallic substrate is held at ambient temperature during evaporation, the molecules form characteristic trimers on the Ag(111) surface and interact through their polar groups. Close to the steps, the molecules form linear structures and seems to stand side by side. On the other hand, after deposition on a substrate cooled at liquid helium temperature, single molecules are observed both on metal and on NaCl. On the ultrathin insulator layers, the STM images present characteristic contrasts related to the molecular orbitals which favors the localization of aldehyde groups. In this case, the lateral molecular interactions may induce the formation of small assemblies in which the electronic levels are slightly shifted. A possible interpretation of this phenomenon is to take into account polar interactions and charge transfer between neighboring molecules. [ABSTRACT FROM AUTHOR]

We report the synthesis, optical, electrochemical and electronic properties of a new perylene derivative and its Ru(II) complex, namely N,-(5-amino-1,10-phenantroline)perylene-3,4,9,10-tetracarboximonoimide (pPDI) and Bis(1,10-phenanthroline)(N-(5-amin-1,10-phenantroline)perylene-3,4,9,10-tetracarboxi monoimide)ruthenium(II) hexafluorophosphate, [Ru(phen) 2 (pPDI)] 2+ ([PF 6 ] − ) 2 . The molecular structures of the compounds were elucidated by FTIR, mass spectrometry, elemental analysis (CHN) and DFT calculations. Their optical and electrochemical properties were investigated by absorption and fluorescence spectroscopy and cyclic voltammetry. The spectroscopic and electrochemical studies for both the pPDI and the perylene monoimide metal complex show that Ru 2+ coordination does not affect the optical and electrochemical properties of the free perylene bisimide ligand. The Ru complex exhibits emission lifetimes of 5.06 ns (48.1%) and 156 ns (51.9%), resulting from emission of the pPDI ligand and 3 MLCT, respectively. The pPDI triplet excited state in the title chromophore is able to sensitize the production of singlet oxygen ( 1 O 2 ). Using a time-resolved laser system, we measured the quantum yield for the production of singlet oxygen (ΦΔ) to be 0.26 for cis -[Ru(phen) 2 (pPDI)] 2+ . Candida albicans is recognized as the most common fungal pathogens, causing superficial infections of the skin and mucous membranes. Resistance of C . albicans strains against classical antifungal agents such as fluconazole has increased considerably, which drives the search for new therapeutic alternatives. In the present study, we report that our new Ru-perylene complex can indeed be used to kill the bacterium C. albicans. The fungicidal activity of cis -[Ru(phen) 2 (pPDI)] 2+ against C. albicans was evaluated in the presence of C. albicans cultures in the dark and in the presence of light. After exposure to 12.5 μM of cis- [Ru(phen) 2 (pPDI)] 2 in the presence of light for 180 s, C. albicans showed a decrease of 50% in its concentration compared to the same experimental conditions in the dark. [ABSTRACT FROM AUTHOR]

By using a closed-aperture (CA) Z-scan technique with a frequency doubled ps and ns Nd: YAG laser, opposite signs of nonlinear refraction (NLR) of N,N′–Bis(2,5,-di-tert-butylphenyl)-3,4,9,10-perylenedicarboximide (DBPI) in acidic (96% sulphuric acid) medium are observed. Using the ps pulses positive effect of NLR is observed (self-focusing). This is attributed to population transitions among singlet states. On the contrary, the ns pulses show negative effect of NLR (self-defocusing), which is attributed to the heat-induced temperature rise induced by acoustic effects and the population relaxation to triplet states. [ABSTRACT FROM AUTHOR]

Polymeric nanoparticles obtained by co-aggregation of a polybenzofulvene derivative with bulky substituted perylene diimide dyes in tetrahydrofuran/water mixtures display emission color tunable from blue to red, or deep-red, thanks to energy transfer processes from the polymer to the emissive dyes activated by nanoparticle shrinking. At high water concentrations the presence of well emissive perylene diimide dye micro-aggregates within the polymer nanoparticles limits the FRET efficiency leading to a combined emission from both the polymer (blue) and the dyes (red and deep-red). The optical properties of the NPs are retained also in the solid state where a weak blue contribution of the polymer emission is observed providing multicolor emission in the films obtained by NPs deposition. [ABSTRACT FROM AUTHOR]

This study aims to explore the unidentified slants of the nature in respect of strengthening and facilitating the usage of memory storage devices to overcome the deficiencies in the existing data storage mechanism. We report three novel asymmetrical perylene diimides (AsPDIs) of linear, V-shaped and star-shaped structures for memory application. These AsPDIs were synthesized from the condensation of 4-aminotriphenylamine (ATPA), 4,4ʹ-diaminotriphenylamine (DATPA), 4,4ʹ,4ʹʹ-triaminotriphenylamine (TATPA), as the electron donor, and N -(2-ethylhexyl)-3,4,9,10-perylenetetracarboxylic acid-3,4-anhydride-9,10-imide (AsPDA), as the electron acceptor. The results of current-voltage (I-V) curves show that PDI-ATPA, PDI-DATPA and PDI-TATPA based memory devices exhibit in respective nonvolatile WORM, nonvolatile Flash and volatile SRAM memory behavior. The ON/OFF current ratios are up to 10 5 and the switching voltages are about 1.4 V, 1.3 V and 2.7 V, respectively. Influence of electron donor/acceptor ratio on the memory behavior was explored and the charge transfer mechanism responsible for the electrical bistability was demonstrated based on the optical, electrochemical results and the molecular simulation results. This study provides suitable candidates and feasible guidance for the advanced memory technology. [ABSTRACT FROM AUTHOR]