Fuel-driven π-conjugated Superstructures to Form Transient Conductive Hydrogels.

Despite advances in creating dissipative materials with transient properties, such as hydrogels and active droplets, their application remains confined to temporal changes in structural properties. Developing out-of-equilibrium materials whose electronic functions are parameterized by a chemical reaction cycle is challenging. Yet, this class of materials is required to construct biomimetic materials. In contrast to traditional chemical reaction cycles that exploit molecularly dissolved building blocks at thermodynamic equilibrium, we show that fiber structures derived from reactive naphthalene diimide (NDI) building blocks can be used as resting states to form far-from-equilibrium conductive hydrogels after the addition of chemical fuels. Upon fueling the NDI-derived fibers, a dual-component activation and deactivation pathway is deduced by kinetic analysis and is absent when using a molecularly dissolved resting state. Investigating the solid-state morphologies of the structures formed throughout the fuel-driven reaction cycle using cryo-EM reveals that the resting thermodynamic fibers evolve to transient thicker fibrils and layered superstructures. We show that the transient redox-active hydrogels exhibit a nearly threefold increase in electrical conductivity upon fuel consumption before reverting to their original value over hours. These far-from-equilibrium materials are potential candidates in applications such as programmable biorobotics and chemical computing.

Naphthalene Diimide-Based Cyanovinylene-Containing Conjugated Organic Polymers for Efficient Lithium-Ion Battery Electrodes.

The pursuit of innovative organic materials and the examination of the "structure-function" correlation in lithium-ion batteries (LIBs) are crucial and highly desirable. Current research focuses on the creation of novel conjugated organic polymers with polycarbonyl groups and examining the impact of electrode structure on the function of lithium-ion batteries. In this paper, two novel cyanovinylene-based conjugated organic polymers, NBA-TFB and NBA-TFPB, are synthesized using a Knoevenagel condensation reaction with naphthalene diimide as the integral unit. The performance of NBA-TFB and NBA-TFPB as cathodes in lithium-ion batteries is investigated. Improved conductivity and increased active site density in NBA-TFPB resulted in superior electrochemistry compared to NBA-TFB. Specifically, NBA-TFPB exhibited a larger reversible capacity (87.58 mAh g-1 at 0.2C and 88.34% retention after 100 cycles), exceptional rate capability (66.13 mAh g-1 at 5C), and robust cycling stability (99.58% coulombic efficiency at 1C and 60.71% retention after 2000 cycles). This study expands the family of diimide-based naphthalene polymers and provides a strategy for enhancing the performance of organic electrode materials containing polycarbonyl structure.

Fast and Efficient Sensing of Drugs in Water Using Self-Assembling D-Glucamine-Functionalized Naphthalenediimide and 1,8-Naphthalimide Fluorophores.

Fast and sensitive quantification of drugs as emerging pollutants in water bodies is a pressing need in contemporary society, to prevent serious environmental concerns that could negatively impact on human health. This explains the surge of interest in this field, and the need to identify highly selective sensing systems. Addressing this issue, in this work we synthesized two D-glucamine functionalized fluorophores bearing self-assembling cores, as 1,8-naphthalimide and naphthalene diimide. We studied their self-assembly in water solution, and characterized the aggregated formed by determining their stability constant, their morphology and size by scanning electron microscopy, resonance light scattering and dynamic light scattering, as well their solid-state emission ability. Then, we studied their sensing ability, in water, towards pharmaceutically active compounds such as ciprofloxacin, nalidixic acid, carbamazepine and diclofenac sodium salt, by fluorescence investigation. Data collected show that the self-assembling ability is significantly affected by the fluorophore structure, which in turn also determines sensing ability. In particular, the naphtalene diimide-based probe was the most sensitive, with LOD as low as 0.01 µM in the presence of nalidixic acid, which is in line and competitive with more complex sensing systems, recently reported in the literature.

Magnetic Properties of Self-Assemble Naphthalene Diimide Radical Aggregates.

The concept of creating room-temperature ferromagnets from organic radicals proposed nearly sixty years ago, has recently experienced a resurgence due to advances in organic radical chemistry and materials. However, the lack of definitive design paradigms for achieving stable long-range ferromagnetic coupling between organic radicals presents an uncertain future for this research. Here, an innovative strategy is presented to achieve room-temperature ferromagnets by assembling π-conjugated radicals into π-π stacking aggregates. These aggregates, with ultra-close π-π distances and optimal π-π overlap, provide a platform for strong ferromagnetic (FM) interaction. The planar aromatic naphthalene diimide (NDI) anion radicals form nanorod aggregates with a π-π distance of just 3.26 Å, shorter than typical van der Waals distances. The suppressed electron paramagnetic resonance (EPR) signal and emergent near-infrared (NIR) absorption of the aggregates confirm strong interactions between the radicals. Magnetic measurements of NDI anion radical aggregates demonstrate room-temperature ferromagnetism with a saturated magnetization of 1.1 emu g-1, the highest among pure organic ferromagnets. Theoretical calculations reveal that π-stacks of NDI anion radicals with specific interlayer translational slippage favor ferromagnetic coupling over antiferromagnetic coupling.

Fluorinated Naphthalene Diimides as Buried Electron Transport Materials Achieve Over 23% Efficient Perovskite Solar Cells.

Naphthalene diimides (NDI) are widely serving as the skeleton to construct electron transport materials (ETMs) for optoelectronic devices. However, most of the reported NDI-based ETMs suffer from poor interfaces with the perovskite which deteriorates the carrier extraction and device stability. Here, a representative design concept for editing the peripheral groups of NDI molecules to achieve multifunctional properties is introduced. The resulting molecule 2,7-bis(2,2,3,3,4,4,4-heptafluorobutyl)benzo[lmn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone (NDI-C4F) incorporated with hydrophobic fluorine units contributes to the prevention of excessive molecular aggregation, the improvement of surface wettability and the formation of strong chemical coordination with perovskite precursors. All these features favor retarding the perovskite crystallization and achieving superior buried interfaces, which subsequently promote charge collection and improve the structural compatibility between perovskite and ETMs. The corresponding PSCs based on low-temperature processed NDI-C4F yield a record efficiency of 23.21%, which is the highest reported value for organic ETMs in n-i-p PSCs. More encouragingly, the unencapsulated devices with NDI-C4F demonstrate extraordinary stability by retaining over 90% of their initial PCEs after 2600 h in air. This work provides an alternative molecular strategy to engineer the buried interfaces and can trigger further development of organic ETMs toward reliable PSCs.

Design and synthesis of dual functional NBD-fluorophore-incorporated naphthalene diimide derivatives as G-quadruplex ligands.

Nitrobenzoxadiazole (NBD)-incorporated naphthalene diimide derivatives were designed and synthesized as candidates of antitumor agents with cytotoxicity against human pancreatic cancer cell MIA PaCa-2. Among these, compounds 1NND and 3NND exhibited fluorescent "turn-off" property toward human telomeric G-quadruplex (G4), which allows the direct measurement of dissociation constant (Kd) of ligands against G4 by fluorescence titration method. Notably, the compound 1NND not only exhibited great cytotoxic activity against MIA PaCa-2 with a half maximal inhibitory concentration (IC50) of 77.9 nM, but also exhibited high affinity against G4 with Kd of 1.72 µM. Furthermore, the target binding properties were investigated by circular dichroism (CD) spectra and further studied by molecular docking methods.

Nanostructured Molecular Packing of Polymer Films Formed on Water Surfaces.

In this study, we examined the nanostructured molecular packing and orientations of poly[[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)] (P(NDI2OD-T2)) films formed on water for the application of nanotechnology-based organic electronic devices. First, the nanoscale molecule-substrate interaction between the polymer and water was modulated by controlling the alkyl side chain length in NDI-based copolymers. Increasing alkyl side chain lengths induced a nanomorphological transition from face-on to edge-on orientation, confirmed by molecular dynamics simulations revealing nanostructural behavior. Second, the nanoscale intermolecular interactions of P(NDI2OD-T2) were controlled by varying the volume ratio of the high-boiling-point additive solvent in the binary solvent blends. As the additive solvent ratio increased, the nanostructured molecular orientation of the P(NDI2OD-T2) films on water changed remarkably from edge-on to bimodal with more face-on crystallites, thereby affecting charge transport. Our finding provides essential insights for precise nanoscale morphological control on water substrates, enabling the formation of high-performance polymer films for organic electronic devices.

Biotinylated cyclic naphthalene diimide as a searching tool for G4 sites on the genome.

A biotinyl cyclic naphthalene diimide (biotinyl cNDI) (1), in which biotin is introduced on the cyclic linker chain of cNDI with high G-quadruplex (G4) specificity, was synthesized. 1 was used for binding analysis to G4 DNAs such as c-myc, c-kit, CEGF, or TA-core. The results showed that 1 bind to G4 DNAs with high affinity and, especially, two molecules of 1 bind to c-myc DNA from top and bottom of G4 site at K = 3.9 × 10-6 M-1 without changing the G4 structure. As a pulldown assay, 1 and streptavidin magnetic beads could be used to recover a c-myc DNA or 120-mer DNA fragment having single c-myc sequence. The qPCR results for the 120-meric DNAs showed that more than 50% of genomic DNA fragments could be recovered by this pulldown assay. The results obtained here might allow the recovery of G4-containing DNA fragments from genomic DNA to analyze the true G4 present in the genome.

Commercializable Naphthalene Diimide Anolytes for Neutral Aqueous Organic Redox Flow Batteries.

Neutral aqueous organic redox flow batteries (AORFBs) hold the potential to facilitate the transition of renewable energy sources from auxiliary to primary energy, the commercial production of anolyte materials still suffers from insufficient performance of high-concentration and the high cost of the preparation problem. To overcome these challenges, this study provides a hydrothermal synthesis methodology and introduces the charged functional groups into hydrophobic naphthalene diimide cores, and prepares a series of high-performance naphthalene diimide anolytes. Under the synergistic effect of π-π stacking and H-bonding networks, the naphthalene diimide exhibits excellent structural stability and the highest water solubility (1.85 M for dex-NDI) reported to date. By employing the hydrothermal method, low-cost naphthalene diimides are successfully synthesized on a hundred-gram scale of $0.16 g-1 ($2.43 Ah-1), which is also the lowest price reported to date. The constructed full battery achieves a high electron concentration of 2.4 M, a high capacity of 54.4 Ah L-1, and a power density of 318 mW cm-2 with no significant capacity decay observed during long-duration cycling. These findings provide crucial support for the commercialization of AORFBs and pave the way for revolutionary developments in neutral AORFBs.

Naphthalene Diimide-Based Metallacage as an Artificial Ion Channel for Chloride Ion Transport.

Developing synthetic molecular devices for controlling ion transmembrane transport is a promising research field in supramolecular chemistry. These artificial ion channels provide models to study ion channel diseases and have huge potential for therapeutic applications. Compared with self-assembled ion channels constructed by intermolecular weak interactions between smaller molecules or cyclic compounds, metallacage-based ion channels have well-defined structures and can exist as single components in the phospholipid bilayer. A naphthalene diimide-based artificial chloride ion channel is constructed through efficient subcomponent self-assembly and its selective ion transport activity in large unilamellar vesicles and the planar lipid bilayer membrane by fluorescence and ion-current measurements is investigated. Molecular dynamics simulations and density functional theory calculations show that the metallacage spans the entire phospholipid bilayer as an unimolecular ion transport channel. This channel transports chloride ions across the cell membrane, which disturbs the ion balance of cancer cells and inhibits the growth of cancer cells at low concentrations.

Synthesis, Photophysical Properties and Self-Assembly of a Tetraphenylethylene-Naphthalene Diimide Donor-Acceptor Molecule.

The development of new π-conjugated molecular structures with controlled self-assembly and distinct photophysical properties is crucial for advancing applications in optoelectronics and biomaterials. This study introduces the synthesis and detailed self-assembly analysis of tetraphenylethylene (TPE) functionalized naphthalene diimide (NDI), a novel donor-acceptor molecular structure referred to as TPE-NDI. The investigation specifically focuses on elucidating the self-assembly behavior of TPE-NDI in mixed solvents of varying polarities, namely chloroform: methylcyclohexane (CHCl3 : MCH) and chloroform: methanol (CHCl3 : MeOH). Employing a several analytical methodologies, including UV-Vis absorption and fluorescence emission spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and dynamic light scattering (DLS), these self-assembled systems have been comprehensively examined. The results reveal that TPE-NDI manifests as distinct particles in CHCl3 : MCH (fMCH =90 %), while transitioning to flower-like assemblies in CHCl3 : MeOH (fMeOH =90 %). This finding underscores the critical role of solvent polarity in dictating the morphological characteristics of TPE-NDI self-assembled aggregates. Furthermore, the study proposes a molecular packing mechanism, based on SEM data, offering significant insights into the design and development of functional supramolecular systems. Such advancements in understanding the molecular self-assembly new π-conjugated molecular structures are anticipated to pave the way for novel applications in material science and nanotechnology.

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.

The Electronic Properties of Cadmium Naphthalene Diimide Coordination Complex.

The computational simulations for electronic properties of cadmium (Cd) coordinated L-alanine NDI ligand (H2-l-ala NDI) based complex are the focus of this research. For the first time, the Cd-NDI complex (monomer) has been produced using water as the solvent; this is a new approach to synthesizing the Cd-NDI complex that has not been reported yet. Along with crystallography and Hirsch field analysis, CAM-B3LYP/LANL2DZ and B3LYP/LANL2MB basis sets were used, and in-depth characterisation of the Cd-NDI complex by following DFT and TD-DFT hypothetical simulations. Hyperpolarizabilities, frontier molecular orbitals (FMOs), the density of states (DOS), dipole moment (µ), electron density distribution map (EDDM), transition density matrix (TDM), molecular electrostatic potential (MEP), electron-hole analysis (EHA), and electrical conductivity (σ) have all been studied regarding the Cd-NDI complex. The vibrational frequencies and types of interaction are studied using infrared (IR) and non-covalent interaction (NCI) analysis with iso-surface. In comparison to the Cd-NDI complex with 2.61, 2.42 eV Eg (using CAM-B3LYP/LANL2DZ and B3LYP/LANL2MB basis sets, respectively) and 376 nm λmax, (in case of B3LYP/LANL2MB λmax is higher), H2-l-ala NDI have 3.387 eV Eg and 375 nm λmax, metal-ligand coordination in complex dramatically altered charge transfer properties, such as narrowing band gap (Eg). Based on the electronic properties analysis of Cd-NDI complex, it is predicted that the Cd-NDI complex will have a spectacular (nonlinear optical) NLO response. The Cd-NDI complex is discovered to be advantageous for the creation of future nanoscale devices due to the harmony between the Cd metal and H2-l-ala NDI, in addition to their influences on NLO characteristics.

Cathode Interlayer Based on Naphthalene Diimide: A Modification Strategy for Zinc-Oxide-Free Inverted Organic Solar Cells.

Perylene diimide with ammonium oxide as a terminal group (named PDIN-O) is a well-known cathode interlayer in conventional-type organic solar cells (OSCs). Since naphthalene diimide exhibits a lower LUMO level than perylene diimide, we chose it as a core to further control the LUMO level of the materials. Small molecules (SMs) produce a beneficial interfacial dipole by the end of ionic functionality at the side chain of naphthalene diimide. With the active layer based on a nonfullerene acceptor (PM6:Y6BO), the power conversion efficiency (PCE) is enhanced by utilizing SMs as cathode interlayers. We discovered that the inverted-type OSC with naphthalene diimide with oxide as a counteranion (NDIN-O) shows poor thermal stability, which can cause irreversible damage to the interlayer-cathode contact, leading to poor PCE (11.1%). To overcome the disadvantage, we introduce NDIN-Br and NDIN-I with a higher decomposition temperature. An excellent PCE of 14.6% was achieved with the device based on NDIN-Br as an interlayer, which is almost the same as the PCE of the ZnO-based device (15.0%). The device based on NDIN-I without the ZnO layer exhibits an improved PCE of 15.4%, which is slightly higher than the ZnO-based device. The result offers a replacement of the ZnO interlayer, which is necessary to carefully manage the sol-gel transition by annealing temperatures as high as 200 °C and leading to low-cost manufacture of OSCs.

Synthesis, Solution, and Solid State Properties of Homological Dialkylated Naphthalene Diimides-A Systematic Review of Molecules for Next-Generation Organic Electronics.

This systematic study aimed at finding a correlation between molecular structure, solubility, self-assembly, and electronic properties of a homological series of N-alkylated naphthalene diimides (NDIs). NDIs are known for their n-type carrier mobility and, therefore, have potential in the field of organic electronics, photovoltaics, and sensors. For the purpose of this study, nine symmetrical N,N'-dialkylated naphthalene diimides (NDIC3-NDIC11) were synthesized in the reaction of 1,4,5,8-naphthalenetetracarboxylic dianhydride with alkylamines ranging from propyl- to undecyl-. The NDIs were characterized by spectroscopic (NMR, UV-Vis, FTIR), microscopic, and thermal methods (TGA and DSC), and X-ray diffraction (XRD). Our experimental study, extensively referring to findings reported in the literature, indicated that the NDIs revealed specific trends in spectroscopic and thermal properties as well as solubility and crystal morphology. The solubility in good solvents (chloroform, toluene, dichlorobenzene) was found to be the highest for the NDIs substituted with the medium-length alkyl chains (NDIC5-NDIC8). Systematic FTIR and XRD studies unraveled a distinct parity effect related to the packing of NDI molecules with odd or even numbers of methylene groups in the alkyl substituents. The NDIs with an even number of methylene groups in the alkyl substituents revealed low-symmetry (P1-) triclinic packing, whereas those with an odd number of carbon atoms were generally monoclinic with P21/c symmetry. The odd-even parity effect also manifested itself in the overlapping of the NDIs' aromatic cores and, hence, the π-π stacking distance (dπ-π). The odd-numbered NDIs generally revealed slightly smaller dπ-π values then the even-numbered ones. Testing the NDIs using standardized field-effect transistors and unified procedures revealed that the n-type mobility in NDIC6, NDIC7, and NDIC8 was 10- to 30-fold higher than for the NDIs with shorter or longer alkyl substituents. Our experimental results indicate that N,N'-alkylated NDIs reveal an optimum range of alkyl chain length in terms of solution processability and charge transport properties.

Synthesis, Solvatochromism and Fluorescence Quenching Studies of Naphthalene Diimide Dye by Nano graphene oxide.

A naphthalene diimide dye with two side amine arm was prepared. Uv-Vis and fluorescence spectroscopic techniques are used for their photophysical and solvatochromic characteristics in different solvents. The Lippert-Mataga plot for naphthalene diimide demonstrated a negative linear dependence by increasing polarity. Results showed naphthalene diimide is more polar in the ground than in the excited state. A quenching study was conducted for interacting the naphthalene diimide as a fluorophore and graphene oxide as a quencher. Fluorescence quenching-based platforms in nanoscale have been used in sensing systems. Raman, FTIR, Uv-Vis and fluorescence spectroscopic techniques were used to study the quenching mechanism. The results indicated that graphene plays an effective quencher against the naphthalene diimide, with a quenching efficiency 91%. The Stern-Volmer analysis results show a mix of static and dynamic quenching mechanisms. The binding constant of the quencher-fluorophore and the number of binding sites have been reported. Thermodynamic parameters of their interaction were evaluated. The negative values of the Gibbs free energy confirm that the complexation process is spontaneous. Meanwhile, the positive entropy value confirms that the favorable pathway process.

N-Type Doping of Naphthalenediimide-Based Random Donor-Acceptor Copolymers to Enhance Transistor Performance and Structural Crystallinity.

An integrated strategy of molecular design and conjugated polymer doping is proposed to improve the electronic characteristics for organic field effect transistor (OFET) applications. Here, a series of soluble naphthalene diimide (NDI)-based random donor-acceptor copolymers with selenophene π-conjugated linkers and four acceptors with different electron-withdrawing strengths (named as rNDI-N/S/NN/SS) are synthesized, characterized, and used for OFETs. N-type doping of NDI-based random copolymers using (12a,18a)-5,6,12,12a,13,18,18a,19-octahydro-5,6-dimethyl-13,18[1',2']-benzenobisbenzimidazo[1,2-b:2',1'-d]benzo[i][2.5]benzodiazocine potassium triflate adduct (DMBI-BDZC) is successfully demonstrated. The undoped rNDI-N, rNDI-NN, and rNDI-SS samples exhibit ambipolar charge transport, while rNDI-S presents only a unipolar n-type characteristic. Doping with DMBI-BDZC significantly modulates the performance of rNDI-N/S OFETs, with a 3- to 6-fold increase in electron mobility (µe) for 1 wt % doped device due to simultaneous trap mitigation, lower contact resistance (RC), and activation energy (EA), and enhanced crystallinity and edge-on orientation for charge transport. However, the doping of intrinsic pro-quinoidal rNDI-NN/SS films exhibits unchanged or even reduced device performance. These findings allow us to manipulate the energy levels by developing conjugated copolymers based on various acceptors and quinoids and to optimize the dopant-polymer semiconductor interactions and their impacts on the film morphology and molecular orientation for enhanced charge transport.

Self-Doping Naphthalene Diimide Conjugated Polymers for Flexible Unipolar n-Type OTFTs.

The development of high-performance organic thin-film transistor (OTFT) materials is vital for flexible electronics. Numerous OTFTs are so far reported but obtaining high-performance and reliable OTFTs simultaneously for flexible electronics is still challenging. Herein, it is reported that self-doping in conjugated polymer enables high unipolar n-type charge mobility in flexible OTFTs, as well as good operational/ambient stability and bending resistance. New naphthalene diimide (NDI)-conjugated polymers PNDI2T-NM17 and PNDI2T-NM50 with different contents of self-doping groups on their side chains are designed and synthesized. The effects of self-doping on the electronic properties of resulting flexible OTFTs are investigated. The results reveal that the flexible OTFTs based on self-doped PNDI2T-NM17 exhibit unipolar n-type charge-carrier properties and good operational/ambient stability thanks to the appropriate doping level and intermolecular interactions. The charge mobility and on/off ratio are fourfold and four orders of magnitude higher than those of undoped model polymer, respectively. Overall, the proposed self-doping strategy is useful for rationally designing OTFT materials with high semiconducting performance and reliability.

Synergistic effect of naphthalenediimide and squaraine ligand targeting G-quadruplex DNA in cancer cells.

Targeting and stabilizing nonclassical DNA G-quadruplexes (G4s) with a ligand to inhibit cell proliferation is a very promising approach for cancer treatment. Here, we demonstrate that the combination of a naphthalenediimide (NDI) ligand and a squaraine ligand significantly improves the anticancer activity of either ligand alone. The NDI ligand binds the 5'-terminal of hybrid-type G4s and induces the topological conversion from a metastable hybrid to a stable parallel conformation, which allows the end-stacking of the squaraine ligand on the 3'-terminal of the resultant parallel-type G4 structure. Moreover, the NDI ligand promotes the diffusion of the squaraine ligand into the nucleus, and the synergistic effect of the two ligands improves the stability of G4s in cancer cells, blocks the cell cycle in the sub-G1 phase, and induces the DNA damage response. These findings will be helpful in the development of combinational ligands targeting DNA G4s with enhanced bioactivity toward the inhibition of cancer cell proliferation.

Novel Polyelectrolytes Based on Naphthalene Diimide with Different Counteranions for Cathode Interlayers in Polymer Solar Cells.

We synthesized novel polyelectrolytes based on naphthalene diimide with quaternary amine featuring hydroxyl groups at the side chain, along with different counteranions (PF-NDIN-Br-OH and PF-NDIN-I-OH) for polymer solar cell (PSC) application as the interlayer. The polyelectrolytes establish a beneficial interface dipole through the ionic moieties and synergistic effects arising from the hydroxyl groups located at the side chain. Incorporating polyelectrolytes as the cathode interlayer resulted in an enhancement of the power conversion efficiency (PCE). The PCE of the device with PF-NDIN-Br-OH increased from 8.96% to 9.51% compared to the ZnO-only device. The best PCE was obtained with the device based on PF-NDIN-I-OH, up to 9.59% resulting from the Jsc enhancement. This outcome implies a correlation between the performance of the device and the synergistic effects observed in polyelectrolytes containing hydroxyl groups in the side chain, along with larger anions when employed in PSCs.