Synthesis and near-infrared characteristics of novel perylene bisimide dyes bay-functionalized with naphthalimide chromophores

Novel perylene bisimide dyes bay-functionalized with naphthalimide chromophores have been prepared conveniently by coupling of 1,8-naphthalimide and dibromoperylene bisimides. Their optical properties were investigated by UV-vis and fluorescence spectroscopy. The absorption spectra of these compounds showed wide spectral responses from 300 to 700 nm, which would be potentials for application as organic solar cells.

High Charge Mobility of a Perylene Bisimide Dye with Hydrogen-bond Formation Group

A perylene bisimide dye covalently bonded with a hydrogen-bond formation group of 1, 3, 5-triazine-2, 4-diamine has been synthesized. Its casting films show a charge carrier mobility over 10^-3 cm^2/Vs, which is in the range of the highest values found for other promising charge transport materials suitable for solution processable technique.

Stable Radical TEMPO Terminated Perylene Bisimide(PBI) Based Small Molecule as Cathode Interlayer for Efficient Organic Solar Cells

By combining stable radical tetramethylpiperidine nitrogen oxide(TEMPO)as end groups and perylene bisimide(PBI)as the core,a small molecular cathode interlayer(CIL)(PBI-TEMPO)was synthesized.Detailed physical-chemical characterizations indicate that PBI-TEMPO can form smooth film,owns low unoccupied molecular orbital(LUMO)level of−3.67 eV and can reduce the work function of silver electrode.When using PBI-TEMPO as CIL in non-fullerene organic solar cells(OSCs),the PM6:BTP-4Cl based OSCs delivered high power conversion efficiencies(PCEs)up to 17.37%,higher than those using commercial PDINO CIL with PCEs of 16.95%.Further device characterizations indicate that PBI-TEMPO can facilitate more efficient exciton dissociation and reduce charge recombination,resulting in enhanced current density and fill factor.Moreover,PBI-TEMPO displays higher thermal stability than PDINO in solution.When PBI-TEMPO and PDINO solution were heated at 150℃ for 2 h and then were used as CIL in solar cells,PBI-TEMPO-based OSCs provided a PCE of 15%,while PDINO-based OSCs only showed a PCE of 10%.These results demonstrate that incorporating TEMPO into conjugated materials is a useful strategy to create new organic semiconductors for application in OSCs.

Perylene Bisimides as efficient electron transport layers in planar heterojunction perovskite solar cells

Two perylene bisimides based non-fullerene small molecules, H-DIPBI and B-DIPBI, are applied into inverted planar heterojunction perovskite solar cells. The power conversion efficiency up to 11.6% has been achieved for device with B-DIPBI,indicating that non-fullerene acceptor can function as the electron transport layer to replace PCBM in perovskite solar cells.

Orthogonal carbazole-perylene bisimide pentad:a photoconversion-tunable photosensitizer with diversified excitation and excited-state relaxation pathways

Integrating multiple photosensitive properties into an“all-in-one”photosensitizer(PS)shows great promise for the treatment of cancers owing to synergistic effect among them.However,the development of such PSs,especially those that need a single laser source,remains a challenge.Herein,we report an orchestration of electron donors and acceptors in a propeller-like pentad,PBI-4Cz,where four carbazole(Cz)units are covalently linked to the ortho-positions of the perylene bisimide(PBI)core.Strong intramolecular donor-acceptor interaction significantly quenches the luminescence and largely extends the absorption spectra to near-infrared region.Excited-state dynamics investigated via femto-and nano-second transient absorption spectroscopy revealed exclusive charge separation of the PBI-4Cz within initial 0.5 ps when photoexcited regardless of which intermediate is involved.Energy dissipation of the resulting charge-separated state(PBI^(•−)-4Cz^(•−))is subjected to the toggle between intersystem-crossing toward excited triplet states and charge recombination toward ground states.Relative importance of the two pathways can be tuned by micro-environmental polarity,which endows PBI-4Cz remarkable performances of singlet-oxygen generation(>90.0%)in toluene and photothermal conversion(∼28.6%)in DMSO.Harnessing intrinsic photostability and excited-state processes of heavy-atom-free PBI derivatives not only holds a promise for multifunctional phototheranostics,but also provides a prototype for designing high-performance PSs with tunable photoconversion pathways.

Bisperylene Bisimide Based Conjugated Polymer as Electron Acceptor for Polymer-Polymer Solar Cells

Perylene bisimide （PBI） unit has been widely used to design conjugated materials, which can be used as electron acceptor in organic solar ceils due to its strong electron-deficient ability. In this work, a conjugated polymer based on PBI dimer as monomer was designed, synthesized, and compared to the conjugated polymer containing single PBI as repeating units. The two conjugated polymers were found to have similar molecular weight, absorption spectra and energy levels. Density functional theory calculation revealed that the PBI dimer-based polymer exhibited highly twisted conjugated backbone due to the large dihedral angle between the two PBI units. The PBI-based polymers as electron acceptor were applied into polymer-polymer solar cells, in which PBI dimer-based polymer solar cells were found to show a high short circuit current density （Jsc = 11.2 mA.cm-2） and a high power conversion efficiency （PCE） of 4.5%. In comparison, the solar cells based on PBI-based polymer acceptor only provided a dsc of 7.2 mA.cm-2 and PCE of 2.5%. The significantly enhanced PCE in PBI dimer-based solar cells was attributed to the mixed phase in blended thin films, as revealed by atom force microscopy. This study demonstrates that PB! dimer can be used to design polymer acceptors for high performance polymer- polymer solar cells.

Synthesis of highly fluorescent and water soluble perylene bisimide

Designed and synthesized a new highly water soluble N,N^1-bis（2-（（5-（（dimethylamino）methyl）furan-2-yl）methylthio）ethyl）-perylene -3,4,9,10-tetracarboxylic diimide from 2-（（5-（（dimethylamino）methyl）furan-2-yl）methylthio）ethanamine and perylene-3,4,9,10- tetracarboxylic dianhydride.The compound was characterized by ~1H,^（13）C,2D NMR,mass and IR techniques.The compound is highly fluorescent with good solubility in water and other polar solvents.

Ethynyl-linked perylene bisimide based electron acceptors for non-fullerene organic solar cells

In this work, star-shaped perylene bisimide（PBI） derivatives with spiro-aromatic cores linked with ethynyl units were developed as electron acceptors for non-fullerene organic solar cells. The ethynyl linkers were found to enhance the planarity of the conjugated backbone, resulting in high electron mobilities and near-infrared absorption. The ethynyl-linked PBI acceptors showed high power conversion efficiencies（PCEs） up to 4.27% due to the high short-circuit current density（Jsc） of 8.52 mA/cm^2 and fill factor（FF） of 0.59, while the PBI acceptor without ethynyl units provided a low PCE of 3.57% in nonfullerene solar cells. The results demonstrate that ethynyl units can be applied into designing new PBI electron acceptors with improved charge transport properties and photovoltaic performance.

A Configurationally Tunable Perylene Bisimide Derivative-based Fluorescent Film Sensor for the Reliable Detection of Volatile Basic Nitrogen towards Fish Freshness Evaluation

Rapid and real-time mon itoring of food quality plays critical roles in the food industry and for the gen era I public health.Herei n,we specially synthesized a new perylene bisimide(PBI)derivative(PCB-EpE)composed of two PBI units and a rigid o-carborane linker,which was further employed in constructi ng a con ceptual fluoresce nt film sen sor for evaluati ng fish fresh ness.Photophysical studies indicate that PCB-EpE displays an open"Z-type"molecular configuration in chloroform and a closed"△-type"configuration in methyl cyclohexa ne.Comparatively,"Z-type"molecular configurati on possesses higher fluoresce nee qua ntum yield and is more sen sitive toward volatile basic nitrogen(VBN).

A Cathodic Electrochromic Material Based on Thick Perylene Bisimide Film with High Optical Contrast and High Stability

Cathodic electrochromic materials realized by n-type doping of conducting polymers are scarce.Even with limited cases reported in the literature,long-term stability is an urgent problem to be solved.Herein,we report a high performance and stable cathodic electrochromic material,poly(Th-Cl-PBI),based on a perylene bisimide function core.Due to its high electropolymerization efficiency and low steric hindrance of thiophene groups,perylene bisimide,which generally does not dissolve and form film easily,can grow to the sufficient thickness of 350 nm for wide-range spectral modulation and large-capacity energy storage.The optical contrast of optimized film with a thickness of 240 nm reaches as high as 69.1% at 520 nm,94.1% at 760 nm,and 95.7% at 680 nm.Theoretical simulation based on the Lambert–Beer law also verifies this optical contrast dependent on film thickness.Besides,during the transition between the neutral state and radical anion state,it maintains 90.2% of the electrochemical activity after 4000 cycles,and the transmittance spectrum remains stable after 2000 cycles.The cation size effect on cathodic electrochromic process and cyclic stability has been investigated.

Excimer Formation of Perylene Bisimide Dyes within Stacking-Restrained Folda-Dimers:Insight into Anomalous Temperature Responsive Dual Fluorescence

We have fabricated a new perylene bisimide(PBI)folda-dimer(BPBI-CB-1)by tethering two PBI moieties to the ortho-carbon positions of a carborane unit.The synthesized compound adopted distinct configurations in different solvents with dual emissions as its characteristic.The two PBI moieties in the molecule appeared either in a weakly interacted,monomer-like state or brought into close π-π contact with each other,forming an interacted stacking state.The equilibrium between these two states was governed by the nature of solvents and testing temperature.Spectroscopic and theoretical studies concluded that dual emission bands originated from intramolecular monomer-like and stacking states,respectively.Remarkably,in a solvent like 1,2-dichloroethane(DCE),both emission intensities increased with rising temperatures.The positive temperature response of the monomer emission was ascribed to an increased amount of monomer-like population,owing to its endothermic energy state,while the excimer emission was rationalized by increased population of the bright exciton state,resulting in an increased emission yield that compensated the diminished population of the stacking state.To our knowledge,this is the first report on positive temperature-responsive dual emissions associated with the synergism of intramolecular intersubunit aggregation/dissociation and excimer transformation.

Impact of Molecular Shape on Supramolecular Copolymer Synthesis in Seeded Living Polymerization of Perylene Bisimides

Supramolecular polymerization properties have been studied for a series of perylene bisimide(PBI)dyes containing identical hydrogen-bonding amide groups in imide positions but variable number or size of alkoxy substituents in bay-positions.

Synthesis and thermal polymerization of perylene bisimide containing benzocyclobutene groups

Fourfold benzocyclobutene-functionalized perylene bisimide（PBI 4） has been synthesized and its structure was characterized by FTIR,MS and NMR.PBI 4 can react either with itself,or the appropriate dienophiles to form the corresponding products under appropriate temperature.The polymer film obtained from the reaction of PBI 4 with methyl vinyl silicone rubber possessed excellent film forming properties including flatness.The optical properties of PBI 4 and polymer film obtained from the reaction of PBI 4 and methyl vinyl silicone rubber have been determined by UV/vis and fluorescence spectroscopy.

Perylene Bisimide In-chain Polyethylene with Unique Self-assembly Nanostructure through Acyclic Diene Metathesis(ADMET)Polymerization

A novel perylene tetracarboxylic acid bisimide（PTCBI） in-chain polyethylene（PE） was first prepared via acyclic diene metathesis（ADMET） polymerization of PTCBI-functionalized α,ω-diene monomer. The polymers could spontaneously self-assemble into hollow cylindrical structures in which the π-π interaction between adjacent PTCBI moieties was enhanced and the electron mobility was possibly promoted. The hydrogenation of as-obtained polymer was readily accomplished, affording the desired precision PTCBI in-chain PE with a saturated backbone, which showed high glass transition temperature（Tg = 63 °C）, relatively wide range of light absorption（λ = 200-575 nm）, and higher LUMO level（-3.62 e V）. It can therefore serve as a superior model for facile construction of functional polyolefin and soluble PTCBI polymer with ordered architecture.

Synthesis and Characterization of Ion-exchange Sulfonated Poly (ether sulfone)

N,N＇-Bis（3-hydroxyphenyl）-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N, N-dimethylformamide. Polymerization of this bisimide with 4,4＇-difluorodiphenylsulfone and disodium 3,3＇-disulfonate4,4＇-difluorodiphenylsulfone gave ion-exchange sulfonated poly（ether sulfone）. The structure of the title compound was characterized with H-NMR and its polymer was characterized with FT-IR.

A new spirofluorene-based nonplanar PBI-dyad and its utilization in the film-based photo-production of singlet oxygen

Traditional photosensitizers are predominantly based on various types of polypyrrole macrocycles, which are generally used in homogeneous and/or suspension states. In the present study, a new non-polypyrrole-based photosensitizer(LW-PBI) was developed via the introduction of a nonplanar spirofluorene into a derivative of perylene bisimides(PBI) containing two longalkyl chains. Photophysical studies demonstrated that the compound shows good solubility in common organic solvents, great photochemical stability, and high absorption efficiency in the visible light region. Due to containing of two energetically matchable, independent fluorescent units, the compound as prepared displays strong tendency to form non-fluorescent chargeseparated states under light irradiation in polar solvents. Based on the merits, LW-PBI was examined for its catalytic property in the photo-production of singlet oxygen in film state. Luckily, the compound is an effective photosensitizer in the generation of the active oxygen species as verified by its unique reaction with uric acid(UA). Further studies revealed that the effective photoproduction of singlet oxygen can be also realized via the utilization of a tiny and low-price LED lamp as a light source and as a film support. Detailed studies on the application of the conceptual device as a medical instrument for photodynamic therapy(PDT) are in progress.

Synthesis and characterization of biodegradable thermoplastic elastomers derived from N.N-bis （2-carboxyethyl）-pyromellitimide, poly（butylene succinate） and polyethylene glycol

Abstract Biodegradable poly（ether-imide-ester） elasto- mers were synthesized from succinic acid, 1,4-butanediol, polyethylene glycol 1000 and N＇,N-bis（2-carboxyethyl）- pyromellitimide which was derived from pyromellitic dianhydride and glycine. The chemical structures, crystal- linities, thermal stabilities, mechanical properties, hydro- philicities and biodegradabilities of these elastomers were investigated. The hard segments of the linear aliphatic poly （ether-ester） exhibited monoclinic chain packing. Increas- ing the amount of aromatic bisimide moieties in the poly （ether-ester） reduced the crystallinity of the material and improved the thermal stability and tensile strength of the elastomers. In addition, introducing a suitable amount of aromatic bisimide moieties into the poly（ether-ester） backbones endowed the elastomers with improved biode- gradability but too many aromatic bisimide groups reduced the biodegradability of the elastomers.

An Isoindigo-Based ＂Double-Cable＂ Conjugated Polymer for SingleComponent Polymer Solar Cells

An isoindigo-based ＂double-cable＂ conjugated polymer bearing perylene bisimide side units was developed via Stille polymerization for application in single-component polymer solar cells, in which a power conversion efficiency of 1% with broad photo-response from 300 nm to 800 nm was achieved. There is no evidence of large phase separation confirmed by AFM images and photoluminescence （PL） spectra. The space charge limit current measurements and light intensity dependence measurements indicate that the low electron mobility and the significant recombination of pho- togenerated charge carriers in active layer mainly account for the low performance of our solar cells. Our results suggest that these ＂double-cable＂ are oromising candidates for use in single-component polymer solar cells with NIR photoresponse.

Efficient Construction of Highly-fused Diperylene Bismides by Cu/Oxalic Diamide-promoted Zipper-mode Double C—H Activation

Copper/oxalic diamide-promoted dimerization of tetrachlorinated perylene bisimide to construct highly-fused diperylene bisimides through Ullmann coupling and zipper-mode double C—H activation has been developed in this study.This one-step reaction combining homocoupling with C—H activation proceeded smoothly under the action of inexpensive metal-ligand system.This protocol is expected to expand the available synthetic tools for condensed ring systems of perylene bisimide(PBIs).