Naphthalene Imide Research Articles

Inhibition Clathrin Mediated Endocytosis: Pitstop 1 and Pitstop 2 Chimeras.

Twenty-five chimera compounds of Pitstop 1 and 2 were synthesised and screened for their ability to block the clathrin terminal domain-amphiphysin protein-protein interaction (NTD-PPI using an ELISA) and clathrin mediated endocytosis (CME) in cells. Library 1 was based on Pitstop 2, but no notable clathrin PPI or in-cell activity was observed. With the Pitstop 1, 16 analogues were produced with 1,8-naphthalic imide core as a foundation. Analogues with methylene spaced linkers and simple amides showed a modest to good range of PPI inhibition (7.6-42.5 μM, naphthyl 39 and 4-nitrophenyl 40 respectively) activity. These data reveal the importance of the naphthalene sulfonate moiety, with no des-SO3 analogue displaying PPI inhibition. This was consistent with the observed analogue docked poses within the clathrin terminal domain Site 1 binding pocket. Further modifications targeted the naphthalene imide moiety, with the installation of 5-Br (45 a), 5-OH (45 c) and 5-propyl ether (45 d) moieties. Among them, the OH 45 c and propyl ether 45 d retained PPI inhibition, with propyl ether 45 d being the most active with a PPI inhibition IC50=7.3 μM. This is 2x more potent than Pitstop 2 and 3x more potent than Pitstop 1.

Multi-Stimuli-Responsive Carbon Dots with Intrinsic Photochromism and In Situ Radical Afterglow.

The combination of advanced photoluminescence characteristics to photochromism is highly attractive in preparing high-performance multifunctional photo-responsive materials for optoelectronic applications. However, this is rather challenging in material design owing to the limited mechanism understanding and construction principles. Here, an effective strategy to integrate photochromism and afterglow emission in carbon dots (CDs) is proposed through embedding naphthaleneimide (NI) structure in CDs followed by polyvinylpyrrolidone (PVP) encapsulation. The NI-structured CDs-PVP shows intrinsic photochromism owing to the in situ formation of NI-radical anions and controllable multi-stimuli-responsive afterglow behaviors related to the oxygen-trigged triplet exciton quenching and Förster resonance energy transfer (FRET) from the pristine CDs to the photoactivated CDs radicals. Notably, a wide range of appearance colors from colorless to brown, luminescence color transition from blue to yellow, and much elongated afterglow lifetime up to 253ms are observed. With the extraordinary stimuli-chromic and stimuli-luminescent CDs-PVP film dynamically responsive to multiple external stimuli, reversible secure snapchat, data encryption/decryption and synaptic imaging recognition are realized. These findings demonstrate a fundamental principle to design multi-stimuli-responsive photochromic CDs with afterglow, providing important understandings on the synergic mechanism of dynamic photochromism and emission behaviors and thereby expanding their applications in advanced information anti-counterfeiting and artificial intelligence.

Redox-active poly(imide-quinone) covalent organic framework anodes for high-efficient and durable aqueous proton batteries

Hydrogen ions (protons), as the lightest and smallest non-metallic charge carriers, have aroused great interest in the field of aqueous batteries. Unfortunately, most anode materials used for these proton batteries still suffer from low specific capacity and/or unsatisfactory cycle durability due to structural deterioration resulted from corrosion of strong acid electrolytes. Here, we report for the first time a robust poly(imide-quinone) (PIQ) covalent organic framework (COF) with dual redox-active naphthalene diimide-paraquinone motifs in its periodic skeletons for proton storage, which can afford a high reversible capacity of ∼ 255.6 mAh/g at a current density of 1 A/g with outstanding cycling stability. The aqueous proton battery (APB) fabricated with this PIQ-COF anode and a copper hexacyanoferrate (CuHCF) cathode demonstrates an unprecedentedly remarkable combination of reversible capacity (about 138 mAh/g at 0.5 A/g), rate capability (76.5 % capacity retention at 20 A/g), and long-term cyclability (99.999 % per cycle for 10,000 cycles at 3 A/g). The ex situ FTIR characterization reveals that the C = O groups in naphthalene imides and paraquinones contribute abundant and accessible redox-active sites for proton storage.

An unprecedented roll-off ratio in high-performing red TADF OLED emitters featuring 2,3-indole-annulated naphthalene imide and auxiliary donors

The annulation of an NMI scaffold at positions 3 and 4 with indole, which has a set of twisted electron-rich substituents at its periphery, allows for the development of high-performance and persistent red-TADF OLED emitters.

Construction of Naphthalene Diimide Derived Nanostructured Cathodes through Self-Assembly for High-Performance Sodium-Organic Batteries.

Organic nanostructured electrodes are very attractive for next-generation sodium-ion batteries. Their great advantages in improved electron and ion transport and more exposed redox-active sites would lead to a higher actual capacity and enhanced rate performance. However, facile and cost-effective methods for the fabrication of nanostructured organic electrodes are still highly challenging and very rare. In this work, we utilize a bioinspired self-assembly strategy to fabricate nanostructured cathodes based on a rationally designed N-hydroxy naphthalene imide sodium salt (NDI-ONa) for high-performance sodium-organic batteries. Such a well-organized nanostructure can greatly enhance both ion and electron transport. When used as cathode for sodium-organic batteries, it provides among the best battery performances, such as high capacity (171 mA h g-1 at 0.05 A g-1), excellent rate performance (153 mA h g-1 at 5.0 A g-1), and ultralong cycling life (93% capacity retention after 20000 cycles at 3.0 A g-1). Even at low temperature or without a conductive additive, it can also perform well. It is believed that self-assembly is a very powerful strategy to construct high-performance nanostructured electrodes.

Solution-processable thermally activated delayed fluorescence red emitters poly(carbazole-fluorene) containing naphthalene imide units

In recent years, the development of solution-processable red-emitting TADF materials has progressed slowly compared to green and blue TADF materials in terms of device efficiency and color purity. This study reports a series of solution-processable red-emitting TADF polymers PCzF-mCP-PXZNAI-X (X = 5, 15, 25, 35), which are designed and synthesized by connecting TADF units (6-(10H-phenoxazin-10-yl)-2-phenyl-1H-benzo[de]isoquinoline-1,3(2H)-dione, PXZNAI) and host units (1,3-bis(N-carbazolyl)benzene, mCP) to the pre-obtained backbone poly(carbazole-fluorene) (PCzF-N3) through the “click” reaction. All the target TADF polymers exhibited good solubility and high thermal stability. Spin-coating PCzF-mCP-PXZNAI-35 as the emission layer, the solution-processed undoped device showed stable red emission with the maximum emission wavelength (λEL) of 647 nm in the operating voltages 8 V–17 V, the maximum external quantum efficiency (EQEmax) of 0.32% and the maximum luminance (Lmax) of 127 cd/m2. The doped device based on PCzF-mCP-PXZNAI-35 using CBP as host material showed orange-red emission with λEL of 619 nm, EQEmax of 2.34% and Lmax of 1938 cd/m2. This result provides a new strategy for the construction of solution-processable stable red-emitting TADF materials.

Naphthalene-imide Self-assembled Monolayers as a Surface Modification of ITO for Improved Thermal Stability of Perovskite Solar Cells

Electron-transport-layer-free (ETL-free) perovskite solar cells (PSCs) show great promise for commercialization due to their simple design and ease of fabrication. However, the interface between the transparent conductive oxides such as indium-doped tin oxide (ITO) and the perovskite is not optimal due to differences in their work functions, surface defects, and wettability of the substrates. Surface modification of ITO through self-assembled monolayers (SAMs) to get ITO/SAM charge selective layers has shown great improvement in device performance in recent years, but little emphasis has been put on the stability of these devices. Here, we address this gap by introducing a series of newly synthesized naphthalene-imide derivatives which self-assemble at the interface between ITO and the perovskite interface and study their impact on the thermal stability of triple-cation PSCs. The chemical and thermal stabilities of the naphthalene-imide SAMs help improve the thermal stability of the devices, reaching T80 lifetimes exceeding 800 h for devices containing a pyridine-functionalized naphthalene diimide carboxylic acid at 85 °C in air. In addition, all SAMs improve the stabilized power output of the devices with respect to ITO-only reference devices. Drift-diffusion simulations reveal the strong influence of the ITO work function on the efficiency in ETL-free devices, and a work function reduction of 0.2 eV could improve efficiencies by over 30%. The functional diversity of naphthalene imides coupled with the ease of SAM deposition opens a pathway for stable, high-performing PSCs based on electron selective monolayers.

Visible light-driven highly-efficient hydrogen production by a naphthalene imide derivative-sensitized TiO2 photocatalyst.

Sensitizing titanium dioxide (TiO2) with dye molecules offers a cost-effective and environmentally friendly strategy for creating powerful photocatalysts for hydrogen production by reducing the band gap and enhancing sunlight absorption. Despite the challenges of identifying a stable dye with high light harvesting efficiency and effective charge recombination, we present a 1,8-naphthalimide derivative-sensitized TiO2 that achieves ultra-efficient photocatalytic hydrogen production (10.615 mmol g-1 h-1) and maintains activity after 30 hours of cycling. Our research offers valuable insights for designing optimized organic dye-sensitized photocatalysts, advancing clean and sustainable energy solutions.

Molecular Pincers Using a Combination of N-H and C-H Donors for Anion Binding.

A naphthalene imide (1) and a naphthalene (2) bearing two pyrrole units have been synthesized, respectively, as anion receptors. It was revealed by 1H NMR spectral studies carried out in CD3CN that receptors 1 and 2 bind various anions via hydrogen bonds using both C-H and N-H donors. Compared with receptor 2, receptor 1 shows higher affinity for the test anions because of the enhanced acidity of its pyrrole NH and naphthalene CH hydrogens by the electron-withdrawing imide substituent. Molecular mechanics computations demonstrate that the receptors contact the halide anions via only one of the two respective available N-H and C-H donors whereas they use all four donors for binding of the oxyanions such as dihydrogen phosphate and hydrogen pyrophosphate. Receptor 1, a push-pull conjugated system, displays a strong fluorescence centered at 625 nm, while receptor 2 exhibits an emission with a maximum peak at 408 nm. In contrast, upon exposure of receptors 1 and 2 to the anions in question, their fluorescence was noticeably quenched particularly with relatively basic anions including F-, H2PO4-, HP2O73-, and HCO3-.

Tuning the “critical polarity” of TICT dyes: Construction of polarity-sensitive platform to distinguish duple organelles

Polarity-sensitive dyes have demonstrated potential applications in bioimaging experiments. However, the twisted intramolecular charge transfer (TICT) mechanism to explain the polarity-responsive behavior still requires in-depth exploration. Herein, we proposed a new concept, “critical polarity”, for the in-depth explanation of TICT mechanism. The polarity below “critical polarity” was defined as “low polarity”, in which the fluorophore would present in local excited (LE) states. The polarity above “critical polarity” was defined as “high polarity”, in which the fluorophore would present in TICT states. Both proper “critical polarity” and large emission difference between LE and TICT states are required to construct desirable dual-emissive fluorophores highly sensitive to polarity. Three fluorescent dyes have been fabricated by modifying different electron donors on naphthalene imide, and S-NAT with modest electron donor demonstrated the highest sensitivity to polarity. Theoretical analysis together with the experimental results proved the validation of “critical polarity” mechanism. Finally, two fluorescent probes have been constructed based on the polarity-sensitive fluorophore. Amongst, the S-NAT could distinguish endoplasmic reticulum (ER) and lipid droplets (LDs) in dual emission colors, while S-NAT-M enabled discrimination of lysosomes and LDs in different emission colors. The two fluorescent probes with high quantum yield and low cytotoxicity could be employed to study the interaction between duple organelles, and the “critical polarity” mechanism can serve as a validate strategy to direct the construction of ratiometric dyes for polarity.

Naphthalene imide derived BODIPY analogues as n-channel semiconductors

BODIPY analogues based on naphthalene mono-imides have been synthesized. The single-crystal X-ray diffraction studies provided evidences for their molecular structures, conformational features and stacking states. The effects of the boron difluoride chelation on the optical and redox properties of the dyes were investigated. The presence of difluoroboranyls in the naphthalene imides led to modifications in the electronic structure of the molecules. The LUMO energy level of the BF2-containing dye (NIPBF) was reduced by 0.15 eV in comparsion with naphthalene-diimides. The field-effect transistors devices based on the BODIPY analogues exhibited typical n-type behavior with electron mobility up to 0.10 cm2 V−1 s−1.

18.5% Efficiency Organic Solar Cells with a Hybrid Planar/Bulk Heterojunction.

The donor:acceptor heterojunction has proved as the most successful approach to split strongly bound excitons in organic solar cells (OSCs). Establishing an ideal architecture with selective carrier transport and suppressed recombination is of great importance to improve the photovoltaic efficiency while remains a challenge. Herein, via tailoring a hybrid planar/bulk structure, highly efficient OSCs with reduced energy losses (Eloss s) are fabricated. A p-type benzodithiophene-thiophene alternating polymer and an n-type naphthalene imide are inserted on both sides of a mixed donor:acceptor active layer to construct the hybrid heterojunction, respectively. The tailored structure with the donor near the anode and the acceptor near the cathode is beneficial for obtaining enhanced charge transport, extraction, and suppressed charge recombination. As a result, the photovoltaic characterizations suggest a reduced nonradiative Eloss by 25 meV, and the best OSC records a high efficiency of 18.5% (certified as 18.2%). This study highlights that precisely regulating the structure of donor:acceptor heterojunction has the potential to further improve the efficiencies of OSCs.

Interface adhesion enhancement by condensed aromatic ring expansion of naphthalene imide derivatives for microvia metallization by copper electroplating

Copper electrodeposition is the preferred approach to fabricate the metallic part of printed circuit board (PCB). However, super-filling of the highly variable topography requires chemical additives, particularly leveler. Herein, three water-soluble naphthalene imide derivatives (NPI) were rationally synthesized and applied as levelers for microvias electrodeposition. Due to the expansion of aromatic ring of naphthalene, the adhesion of NPI to copper surface is improved. Comprehensive electrochemical measurements and microvia deposition experiments demonstrate that the adhesion enhancement of the leveler brings about better filling performance. Theoretical calculations unveiled that the variations of the condensed aromatic ring is the main reason for the change of the bandgap and of the adsorption energy of NPI toward the copper surface. Upon using the heptacyclic NPI (1c) as leveler, a thin copper film with thickness of the order of nanometer was achieved, which is of considerable importance for the building-up high-density-interconnected PCB. Finally, potentiodynamic polarization and secondary ion mass spectrometry measurements were used to investigate the consumption and incorporation of NPI 1c into the copper film upon the deposition process, in order to optimally parametrize the usage of NPI 1c during the copper electrodeposition process.

Efficient Naphthalene Imide-Based Interface Engineering Materials for Enhancing Perovskite Photovoltaic Performance and Stability.

The ways to overcome surface charge recombination and poor interface contact are still the central challenges for the development of inorganic-organic hybrid halide perovskite solar cells (PSCs). [6,6]-Phenyl C61 butyric acid methyl ester (PCBM) is commonly employed in PSCs, but it has some disadvantages including high charge recombination and poor surface coverage. Therefore, the addition of an interfacial engineering layer showing efficient surface passivation, electron extraction, and excellent interface contact can solve the above problems. Furthermore, by employing interface engineering with a spike structure of the energy levels, the reduced energy losses are beneficial to elevating the open-circuit voltage (Voc) in PSCs. Herein, the linear naphthalene imide dimer containing an indacenodithiophene unit (IDTT2NPI) has been developed as an excellent interface engineering material to strengthen the perovskite performance. The introduction of a spike interface on the top of a methylammonium lead triiodide (MAPbI3) film resulted in a high Voc of 1.12 V with the optimal efficiency reaching 20.2%. The efficiency enhancement can be traced to the efficient surface passivation and enhanced interface contact. The mechanism of IDTT2NPI as the interface engineering layer was investigated by both experiments and theoretical calculations. This work provides a promising naphthalene imide-based interfacial material for high-efficiency and stable PSCs.

NIR-Absorbing π-Extended Azulene: Non-Alternant Isomer of Terrylene Bisimide.

The first planar π‐extended azulene that retains aromaticity of odd‐membered rings was synthesized by [3+3] peri‐annulation of two naphthalene imides at both long‐edge sides of azulene. Using bromination and subsequent nucleophilic substitution by methoxide and morpholine, selective functionalization of the π‐extended azulene was achieved. Whilst these new azulenes can be regarded as isomers of terrylene bisimide they exhibit entirely different properties, which include very narrow optical and electrochemical gaps. DFT, TD‐DFT, as well as nucleus‐independent chemical shift calculations were applied to explain the structural and functional properties of these new π scaffolds. Furthermore, X‐ray crystallography confirmed the planarity of the reported π‐scaffolds and aromaticity of their azulene moiety.

Naphthalene imide dimer as interface engineering material: An efficient strategy for achieving high-performance perovskite solar cells

How to design and synthesize interfacial engineered materials that have efficient surface passivation and electron extraction properties is an important problem in the field of optoelectronic materials. Herein, a simple naphthalene imide dimer, namely 2FBT2NDI, is developed by Stille coupling reaction with a high yield, and it is used as interface engineering material for inverted perovskite solar cells (PSCs). Owing to the existence of intermolecular interactions between MAPbI3 and the 2FBT2NDI layer, the introduction of the interfacial layer can passivate the surface defects of perovskite film and improve interface contact. In addition, 2FBT2NDI exhibits suitable energy levels and high electron mobility because of its large linear conjugated skeleton containing two fluorine atoms, which are beneficial for electron extraction for efficient PSCs. By employing 2FBT2NDI as an interfacial layer, inverted PSCs show a maximum power conversion efficiency of 20.1%, which is over 14% higher than that of the control devices without interfacial layer (17.1%). These results highlight that the naphthalene imide dimer can potentially be used as a commercializable interfacial material for achieving high-performance PSCs.

Naphthalene imides as novel p-type sensitizers for NiO-based p-type dye-sensitized solar cells

We report two efficient materials for p-type dye-sensitized solar cells, namely S64 and S85. Novel p-type photosensitizers for NiO-based p-type dye-sensitized solar cells are presented in this study.

Preparation of platinum(II) complexes with naphthalene imide derivatives and exploration of their in vitro cytotoxic activities

Two new platinum(II) complexes with naphthalene imide derivatives as the ligands, [Pt(3a)Cl]Cl (3a-Pt) and [Pt(3b)Cl]Cl (3b-Pt), where 3a = 5‑(3‑(bis(pyridin‑2‑ylmethyl)amino)propoxy)‑2‑phenyl‑1H‑benzo[de]isoquinoline‑1,3(2H)‑dione and 3b = 2‑benzyl‑5‑(3‑(bis(pyridin‑2‑ylmethyl)amino)propoxy)‑1H‑benzo[de]isoquinoline‑1,3(2H)‑dione, were synthesized and structurally characterized. 3b-Pt showed higher anti-tumor properties in vitro against human non-small cell lung cancer NCI-H460 cells (0.89 ± 0.25 μM) than 3a-Pt (11.32 ± 0.47 μM) and cisplatin (11.09 ± 1.01 μM). In addition, 3b-Pt induced NCI-H460 cell apoptosis through inhibition of the telomerase activity and dysfunction of mitochondria.

In vitro and in vivo activity of novel platinum(ii) complexes with naphthalene imide derivatives inhibiting human non-small cell lung cancer cells

3 induced NCI-H460 cell apoptosis via inhibition of the telomerase and dysfunction of mitochondria. Remarkably, 3 obviously inhibited NCI-H460 xenograft tumor growth in vivo.

A naphthalene-based fluorescent probe for ratiometric imaging of lysosomal hydrogen sulfide in living cells

Hydrogen sulfide is an important gasotransmitter that exhibits various functions in physiological processes. We present a ratiometric fluorescence probe (SN-N3) for H2S by functionalizing naphthalene imide with 4-(azidomethyl)benzene as a H2S recognition moiety and morpholine moiety as a lysosomal targeting unit. After reaction with H2S, the azido moiety is reduced to amine group, and the probe releases the self-immolative linker and regenerates the fluorophore with internal charge transfer effect. SN-N3 is responsive to H2S in a ratiometric mode, exhibiting excellent sensitivity and high selectivity. The probe is demonstrated to be localized in lysosomes with high specificity. More importantly, SN-N3 is successfully demonstrated to image lysosomal H2S in a ratiometric manner. Our design provides a novel tool to image H2S in living cells that would hold great potential in exploring various H2S-related physiological and pathological cellular processes.