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Dynamic Covalent Chemistry, consisting in the use of dynamic covalent bonds (DCBs) to create complex objects by working at the thermodynamic equilibrium, has undeniable advantages for the preparation of conjugated systems with tailored optoelectronic properties for organic electronics. Chemists can combine simple building blocks with simple functional groups of appropriate geometry, structure and stoichiometry to build multidimensional conjugated architectures. Dynamic covalent reactions are often precious metal‐free, generate little to no side products and are very efficient. DCBs however afford sensitive materials, and consequently a balance needs to be found between the ease of synthesis, the stability and the performances. The dynamicity of the target materials hence can considerably reduce their applicability in organic electronics where strongly stable materials are needed, but opens the door to stimuli‐responsive behaviour and recyclability. A way to overcome dynamicity issues is to lock DCBs, but often at the cost of decreased conjugation. In this review, we will highlight how DCBs are employed to prepare functional optoelectronically active materials, such as discrete molecules, polymers or covalent organic frameworks, applied in fields ranging from organic light‐emitting diodes and solar cells to organic batteries and transistors. We will also discuss their limitations, benefits and the current challenges to overcome. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) with low crystallinity are promising candidates for application in organic thermoelectrics (OTEs), particularly in flexible devices, because the disordered structures of these CPs can effectively accommodate dopants and ensure robust resistance to bending. However, n‐doped CPs usually exhibit poor thermoelectric performance, which hinders the development of high‐performance thermoelectric generators. Herein, we report an n‐type CP (ThDPP‐CNBTz) comprising two acceptor units: a thiophene‐flanked diketopyrrolopyrrole and a cyano‐functionalized benzothiadiazole. ThDPP‐CNBTz shows a low LUMO energy level of below −4.20 eV and features low crystallinity, enabling high doping efficiency. Moreover, the dual‐acceptor design enhances polaron delocalization, resulting in good thermoelectric performance. After n‐doping, ThDPP‐CNBTz exhibits an average electrical conductivity (σ) of 50.6 S cm−1 and a maximum power factor (PF) of 126.8 μW m−1 K−2, which is among the highest values reported for solution‐processed n‐type CPs to date. Additionally, a solution‐processed flexible OTE device based on doped ThDPP‐CNBTz exhibits a maximum PF of 70 μW m−1 K−2; the flexible device also shows remarkable resistance to bending strain, with only a marginal change in σ after 600 bending cycles. The findings presented in this work will advance the development of n‐type CPs for OTE devices, and flexible devices in particular. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) with low crystallinity are promising candidates for application in organic thermoelectrics (OTEs), particularly in flexible devices, because the disordered structures of these CPs can effectively accommodate dopants and ensure robust resistance to bending. However, n‐doped CPs usually exhibit poor thermoelectric performance, which hinders the development of high‐performance thermoelectric generators. Herein, we report an n‐type CP (ThDPP‐CNBTz) comprising two acceptor units: a thiophene‐flanked diketopyrrolopyrrole and a cyano‐functionalized benzothiadiazole. ThDPP‐CNBTz shows a low LUMO energy level of below −4.20 eV and features low crystallinity, enabling high doping efficiency. Moreover, the dual‐acceptor design enhances polaron delocalization, resulting in good thermoelectric performance. After n‐doping, ThDPP‐CNBTz exhibits an average electrical conductivity (σ) of 50.6 S cm−1 and a maximum power factor (PF) of 126.8 μW m−1 K−2, which is among the highest values reported for solution‐processed n‐type CPs to date. Additionally, a solution‐processed flexible OTE device based on doped ThDPP‐CNBTz exhibits a maximum PF of 70 μW m−1 K−2; the flexible device also shows remarkable resistance to bending strain, with only a marginal change in σ after 600 bending cycles. The findings presented in this work will advance the development of n‐type CPs for OTE devices, and flexible devices in particular. [ABSTRACT FROM AUTHOR]

Supramolecular electronics exploits the distinctive features stemming from noncovalent interactions, guiding the self‐assembly of molecules to craft materials endowed with customized electronic functionalities. Hydrogen‐bonded materials, characterized by their capacity to establish dynamic and stable networks, introduce an extra dimension to the development of supramolecular electronic systems. This study presents a comparative analysis of two remarkably small semiconductors utilizing diketopyrrolopyrrole functionalized with urea units as hydrogen‐bonding motifs, strategically positioned at opposing ends of the conjugated core. We show how the subtle distinction in functionalization not only influences morphology and self‐assembly dynamics via hydrogen‐bonding and π‐π stacking formation, but also holds significant consequences for ultimate charge transport properties. Our observations into the interplay of noncovalent interactions provide valuable insights and strategic pathways for the design of novel materials with enhanced electronic characteristics. [ABSTRACT FROM AUTHOR]

Molecular design is crucial for endowing conjugated polymers (CPs) with unique properties and enhanced electronic performance. Introducing Hydrogen‐bonding (H‐bonding) into CPs has been a broadly exploited, yet still emerging strategy capable of tuning a range of properties encompassing solubility, crystallinity, electronic properties, solid‐state morphology, and stability, as well as mechanical properties and self‐healing properties. Different H‐bonding groups can be utilized to tailor CPs properties based on the applications of interest. This review provides an overview of classes of H‐bonding CPs (assorted by the different H‐bond functional groups), the synthetic methods to introduce the corresponding H‐bond functional groups and the impact of H‐bonding in CPs on corresponding electronic and materials properties. Recent advances in addressing the trade‐off between electronic performance and mechanical durability are also highlighted. Furthermore, insights into future directions and prospects for H‐bonded CPs are discussed. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis and characterization of a series of conjugated porous polymers (CPPs) based on a 2,4,6‐tris(5‐ethynylthiophen‐2‐yl)‐1,3,5‐triazine (TT) core moiety. TT was coupled with several conjugated building blocks as comonomers, including naphthodithiophene, benzodithiophene, bithiophene, tetraphenyl porphyrin, azulene, and perylene diimide, utilizing the Sonogashira‐coupling reaction to produce narrow band gap (1.73–2.19 eV) CPPs. The solid‐state UV‐visible spectra demonstrated broad absorption in 350 nm to 900 nm region, indicating extended π‐conjugation in the polymers. The photophysical properties of the polymers have been tuned by the judicious choice of comonomer. The obtained CPPs exhibit excellent thermal stability, reaching as high as 500 °C, and porosity insights reveal dominance of mesopores and macropores. Morphological studies reveal that 2‐ethylhexyl substituted perylene diimide hinder the stacking amongst the polymeric backbone, resulting in featureless aggregates, whereas the cyclohexyl group on perylene diimide results in well‐defined nanofibrous morphology. These narrow band‐gap CPPs hold promise for applications in energy storage, organic electronics, photocatalysis and sensing technologies. [ABSTRACT FROM AUTHOR]

Oligomers and polymers consisting of multiple thiophenes are widely used in organic electronics such as organic transistors and sensors because of their strong electron-donating ability. In this study, a solution to the problem of the poor solubility of polythiophene systems was developed. A novel π-conjugated polymer material, PDPP-5Th, was synthesized by adding the electron acceptor unit, DPP, to the polythiophene system with a long alkyl side chain, which facilitated the solution processing of the material for the preparation of devices. Meanwhile, the presence of the multicarbonyl groups within the DPP molecule facilitated donor–acceptor interactions in the internal chain, which further improved the hole-transport properties of the polythiophene-based material. The weak forces present within the molecules that promoted structural coplanarity were analyzed using theoretical simulations. Furthermore, the grazing incidence wide-angle X-ray scanning (GIWAXS) results indicated that PDPP-5Th features high crystallinity, which is favorable for efficient carrier migration within and between polymer chains. The material showed hole transport properties as high as 0.44 cm2 V−1 s−1 in conductivity testing. Our investigations demonstrate the great potential of this polymer material in the field of optoelectronics. [ABSTRACT FROM AUTHOR]

Polythiophene, as a class of potential electron donor units, is widely used in organic electronics such as transistors. In this work, a novel polymeric material, PDPPTT-FT, was prepared by incorporating the electron acceptor unit into the polythiophene system. The incorporation of the DPP molecule assists in improving the solubility of the material and provides a convenient method for the preparation of field effect transistors via subsequent solution processing. The introduction of fluorine atoms forms a good intramolecular conformational lock, and theoretical calculations show that the structure displays excellent co-planarity and regularity. Grazing incidence wide-angle X-ray (GIWAXS) results indicate that the PDPPTT-FT is highly crystalline, which facilitates carrier migration within and between polymer chains. The hole mobility of this π-conjugated material is as high as 0.30 cm2 V−1 s−1 in organic transistor measurements, demonstrating the great potential of this polymer material in the field of optoelectronics. [ABSTRACT FROM AUTHOR]

Non‐conjugated pendant electroactive polymers (NCPEPs) are an emerging class of polymers that offer the potential of combining the desirable optoelectronic properties of conjugated polymers with the superior synthetic methodologies and stability of traditional non‐conjugated polymers. Despite an increasing number of studies focused on NCPEPs, particularly on understanding fundamental structure‐property relationships, no attempts have been made to provide an overview on established relationships to date. This review showcases selected reports on NCPEP homopolymers and copolymers that demonstrate how optical, electronic, and physical properties of the polymers are affected by tuning of key structural variables such as the chemical structure of the polymer backbone, molecular weight, tacticity, spacer length, the nature of the pendant group, and in the case of copolymers the ratios between different comonomers and between individual polymer blocks. Correlation of structural features with improved π‐stacking and enhanced charge carrier mobility serve as the primary figures of merit in evaluating impact on NCPEP properties. While this review is not intended to serve as a comprehensive summary of all reports on tuning of structural parameters in NCPEPs, it highlights relevant established structure‐property relationships that can serve as a guideline for more targeted design of novel NCPEPs in the future. [ABSTRACT FROM AUTHOR]

The true structure of alternating conjugated polymers—the state‐of‐the‐art materials for many organic electronics—often deviates from the idealized picture. Homocoupling defects are in fact inherent to the widely used cross‐coupling polymerization methods. Nevertheless, many polymers still perform excellently in the envisaged applications, which raises the question if one should really care about these imperfections. This article looks at the relevance of chemical precision (and lack thereof) in conjugated polymers covering the entire spectrum from the molecular scale, to the micro and mesostructure, up to the device level. The different types of polymerization errors for the alkoxylated variant of the benchmark (semi)crystalline polymer poly[2,5‐bis(3‐tetradecylthiophen‐2‐yl)thieno[3,2‐b]thiophene (PBTTT) are identified, visualized, and quantified and a general strategy to avoid homocoupling is introduced. Through a combination of experiments and supported by simulations, it is shown that these coupling defects hinder fullerene intercalation and limit device performance as compared to the homocoupling‐free analog. This clearly demonstrates that structural defects do matter and should be generally avoided, in particular when the geometrical regularity of the polymer is essential. These insights likely go beyond the specific PBTTT derivatives studied here and are of general relevance for the wider organic electronics field. [ABSTRACT FROM AUTHOR]

In contrast to edge‐on and face‐on orientations, end‐on uniaxial conjugated polymers have the theoretical possibility of providing a macroscopic crystalline film. However, their fabrication is insurmountable due to sluggishly thermodynamic equilibrium states. Herein, we report the programmatic pathway to fabricate nanoarchitectonics on end‐on uniaxial conjugated metallopolymers by surface‐initiated simultaneous electrosynthesis and assembly. Self‐assembled monolayer (SAM) with bottom‐up oriented electroactive molecules as a temple allows orientation, stacking, and reactive addition of monomers triggered by switching alternative redox reactions as well as crystallization of small molecules. Repeating the same reaction can repair the unreactive site on the SAM and dynamically and statistically ensure maximum iterative coverage with ideal linear coefficients between optical or electrical responses and iterative times. The resulting nanoarchitectonics on uniaxially assembled end‐on polymers over centimeter‐sized areas have a subnanometer‐uniform morphology and exhibit ultrahigh modulus as well as an inorganic indium tin oxides and the highest conductance among conjugated molecular monolayers. Their memristive devices provide quantitative electrical and optical responses as a function of molecular length, bias, and iterative junctions. Precise processing of nanoarchitectonics as an electrically assisted assembly or printing technique can present sophisticated optoelectric functions and dimensional batch‐to‐batch consistency for micro‐sized organic materials and electronics. [ABSTRACT FROM AUTHOR]

In contrast to edge‐on and face‐on orientations, end‐on uniaxial conjugated polymers have the theoretical possibility of providing a macroscopic crystalline film. However, their fabrication is insurmountable due to sluggishly thermodynamic equilibrium states. Herein, we report the programmatic pathway to fabricate nanoarchitectonics on end‐on uniaxial conjugated metallopolymers by surface‐initiated simultaneous electrosynthesis and assembly. Self‐assembled monolayer (SAM) with bottom‐up oriented electroactive molecules as a temple allows orientation, stacking, and reactive addition of monomers triggered by switching alternative redox reactions as well as crystallization of small molecules. Repeating the same reaction can repair the unreactive site on the SAM and dynamically and statistically ensure maximum iterative coverage with ideal linear coefficients between optical or electrical responses and iterative times. The resulting nanoarchitectonics on uniaxially assembled end‐on polymers over centimeter‐sized areas have a subnanometer‐uniform morphology and exhibit ultrahigh modulus as well as an inorganic indium tin oxides and the highest conductance among conjugated molecular monolayers. Their memristive devices provide quantitative electrical and optical responses as a function of molecular length, bias, and iterative junctions. Precise processing of nanoarchitectonics as an electrically assisted assembly or printing technique can present sophisticated optoelectric functions and dimensional batch‐to‐batch consistency for micro‐sized organic materials and electronics. [ABSTRACT FROM AUTHOR]

Conjugated polymer semiconductors based on donor–acceptor structures are commonly employed as core materials for optoelectronic devices in the field of organic electronics. In this study, we designed and synthesized a novel acceptor unit thiophene-vinyl-diketopyrrolopyrrole, named TVDPP, based on a four-step organic synthesis procedure. Stille coupling reactions were applied with high yields of polymerization of TVDPP with fluorinated thiophene (FT) monomer. The molecular weight and thermal stability of the polymers were tested and showed high molecular weight and good thermal stability. Theoretical simulation calculations and 2D grazing-incidence wide-angle X-ray scattering (GIWAXS) tests verified the planarity of the material and excellent stacking properties, which are favorable for achieving high carrier mobility. Measurements based on the polymer as an organic thin film transistor (OTFT) device were carried out, and the mobility and on/off current ratio reached 0.383 cm2 V−1 s−1 and 104, respectively, showing its great potential in organic optoelectronics. [ABSTRACT FROM AUTHOR]

The incorporation of insulating polymers into conjugated polymers has been widely explored as a strategy to improve mechanical properties of flexible organic electronics. However, phase separation due to the immiscibility of these polymers has limited their effectiveness. In this study, we report the discovery of multiple non‐covalent interactions that enhances the miscibility between insulating and conjugated polymers, resulting in improved mechanical properties. Specifically, we have added polyvinyl chloride (PVC) into the conjugated polymer PM6 and observed a significant increase in solution viscosity, indicative of favorable miscibility between these two polymers. This phenomenon has been rarely observed in other insulating/conjugated polymer composites. Thin films of PM6/PVC exhibit a much‐improved crack‐onset strain of 19.35 %, compared to 10.12 % for pristine PM6 films. Analysis reveal that a "cyclohexyl‐like" structure formed through dipole‐dipole interactions and hydrogen bonding between PVC and PM6 acted as a cross‐linking site in the thin films, leading to improved mechanical properties. Moreover, PM6/PVC blend films have demonstrated excellent thermal and bending stability when applied as an electron donor in organic solar cells. These findings provide new insights into non‐covalent interactions that can be utilized to enhance the properties of conjugated polymers and may have potential applications in flexible organic electronics. [ABSTRACT FROM AUTHOR]

The incorporation of insulating polymers into conjugated polymers has been widely explored as a strategy to improve mechanical properties of flexible organic electronics. However, phase separation due to the immiscibility of these polymers has limited their effectiveness. In this study, we report the discovery of multiple non‐covalent interactions that enhances the miscibility between insulating and conjugated polymers, resulting in improved mechanical properties. Specifically, we have added polyvinyl chloride (PVC) into the conjugated polymer PM6 and observed a significant increase in solution viscosity, indicative of favorable miscibility between these two polymers. This phenomenon has been rarely observed in other insulating/conjugated polymer composites. Thin films of PM6/PVC exhibit a much‐improved crack‐onset strain of 19.35 %, compared to 10.12 % for pristine PM6 films. Analysis reveal that a "cyclohexyl‐like" structure formed through dipole‐dipole interactions and hydrogen bonding between PVC and PM6 acted as a cross‐linking site in the thin films, leading to improved mechanical properties. Moreover, PM6/PVC blend films have demonstrated excellent thermal and bending stability when applied as an electron donor in organic solar cells. These findings provide new insights into non‐covalent interactions that can be utilized to enhance the properties of conjugated polymers and may have potential applications in flexible organic electronics. [ABSTRACT FROM AUTHOR]

With their bent π‐systems, cyclic conjugation and inherent cavities, conjugated nanohoops are attractive for organic electronics applications. For ease of processing and morphological stability, an incorporation into polymers is desirable, but to date was hampered with few exceptions by synthetic difficulties. We herein present a unique strategy for the synthesis of conjugated nanohoop polymers using a dibenzo[a,e]pentalene (DBP) as central connector. We demonstrate this versatility by synthesizing three electronically diverse copolymers with dithienyldiketo(pyrrolopyrrol), fluorene and carbazole comonomers, and report the first donor‐acceptor nanohoop polymer. Optoelectronic investigations reveal the prevalence of cyclic or linear conjugation, depending on the comonomer unit, and ambipolar electrochemical properties through the antiaromatic character of the DBP units. As the first report on using conjugated nanohoops for charge storage as positive electrode materials, we show a significant improvement in battery performance in a nanohoop‐containing polymer compared to an equivalent nanohoop‐free reference polymer. We believe this study will pave the way for the synthesis of a diverse range of nanohoop polymers and further stimulate their exploration for charge storage in batteries. [ABSTRACT FROM AUTHOR]

With their bent π‐systems, cyclic conjugation and inherent cavities, conjugated nanohoops are attractive for organic electronics applications. For ease of processing and morphological stability, an incorporation into polymers is desirable, but to date was hampered with few exceptions by synthetic difficulties. We herein present a unique strategy for the synthesis of conjugated nanohoop polymers using a dibenzo[a,e]pentalene (DBP) as central connector. We demonstrate this versatility by synthesizing three electronically diverse copolymers with dithienyldiketo(pyrrolopyrrol), fluorene and carbazole comonomers, and report the first donor‐acceptor nanohoop polymer. Optoelectronic investigations reveal the prevalence of cyclic or linear conjugation, depending on the comonomer unit, and ambipolar electrochemical properties through the antiaromatic character of the DBP units. As the first report on using conjugated nanohoops for charge storage as positive electrode materials, we show a significant improvement in battery performance in a nanohoop‐containing polymer compared to an equivalent nanohoop‐free reference polymer. We believe this study will pave the way for the synthesis of a diverse range of nanohoop polymers and further stimulate their exploration for charge storage in batteries. [ABSTRACT FROM AUTHOR]

Large-area single-crystalline thin films of n-type organic semiconductors (OSCs) fabricated via solution-processed techniques are urgently demanded for high-end electronics. However, the lack of molecular designs that concomitantly offer excellent charge-carrier transport, solution-processability, and chemical/thermal robustness for n-type OSCs limits the understanding of fundamental charge-transport properties and impedes the realization of large-area electronics. The benzo[de]isoquinolino[1,8-gh]quinolinetetracarboxylic diimide (BQQDI) π-electron system with phenethyl substituents (PhC2-BQQDI) demonstrates high electron mobility and robustness but its strong aggregation results in unsatisfactory solubility and solution-processability. In this work, an asymmetric molecular design approach is reported that harnesses the favorable charge transport of PhC2-BQQDI, while introducing alkyl chains to improve the solubility and solution-processability. An effective synthetic strategy is developed to obtain the target asymmetric BQQDI (PhC2-BQQDI-Cn). Interestingly, linear alkyl chains of PhC2-BQQDI-Cn (n = 5-7) exhibit an unusual molecular mimicry geometry with a gauche conformation and resilience to dynamic disorders. Asymmetric PhC2-BQQDI-C5 demonstrates excellent electron mobility and centimeter-scale continuous single-crystalline thin films, which are two orders of magnitude larger than that of PhC2-BQQDI, allowing for the investigation of electron transport anisotropy and applicable electronics. [ABSTRACT FROM AUTHOR]

Donor-acceptor (D-A) conjugated polymers comprising electron-deficient aromatic dicarboximide units represent an important type of organic semiconductors, especially for electron transporting properties. Pyrene-1,5,6,10-tetracarboxyl diimide (PyDI), a new PAH dicarboximide molecule recently reported by us, provides a fine balance between the electron-stabilizing ability and π-stacking tendency, as compared to the naphthalenediimide (NDI) and perylenediimide (PDI) analogues. In this study, using thienylene-vinylene-thienylene (TVT) and biselenophene (BS) as the electron donating comonomer, along with PyDI as the acceptor moiety, we develop two new D-A type conjugated polymers, which exhibit impressive electron-transporting performance. Specifically, in the solution-processed OFET devices, electron mobility of 0.18 and 0.20 cm2·V−1·s−1 are achieved with these polymers, respectively. Such findings further prove the optimal potential of PyDI for application as an electron-acceptor building block in the development of polymeric n-type semiconductors among all various high-performance functional D-A polymers. [ABSTRACT FROM AUTHOR]

Organic polymer semiconductor materials are conveniently tuned to energy levels because of their good chemically modifiable properties, thus enhancing their carrier transport capabilities. Here, we have designed and prepared a polymer with a donor-acceptor structure and tested its potential as a p-type material for organic field-effect transistor (OFET) applications using a solution-processing method. The conjugated polymers, obtained via the polymerization of the two monomers relying on the Stille coupling reaction, possess extremely high molecular weights and thermodynamic stability. Theoretical-based calculations show that PDPP-2S-Se has superior planarity, which is favorable for carrier transport within the main chain. Photophysical and electrochemical measurements systematically investigated the properties of the material and the energy levels with respect to the theoretical values. The maximum hole mobility of the PDPP-2S-Se-based OFET device is 0.59 cm2 V−1 s−1, which makes it a useful material for potential organic electronics applications. [ABSTRACT FROM AUTHOR]

Organic mixed ionic–electronic conductors (OMIECs) have varied performance requirements across a diverse application space. Chemically doping the OMIEC can be a simple, low‐cost approach for adapting performance metrics. However, complex challenges, such as identifying new dopant materials and elucidating design rules, inhibit its realization. Here, these challenges are approached by introducing a new n‐dopant, tetrabutylammonium hydroxide (TBA‐OH), and identifying a new design consideration underpinning its success. TBA‐OH behaves as both a chemical n‐dopant and morphology additive in donor acceptor co‐polymer naphthodithiophene diimide‐based polymer, which serves as an electron transporting material in organic electrochemical transistors (OECTs). The combined effects enhance OECT transconductance, charge carrier mobility, and volumetric capacitance, representative of the key metrics underpinning all OMIEC applications. Additionally, when the TBA+ counterion adopts an "edge‐on" location relative to the polymer backbone, Coulombic interaction between the counterion and polaron is reduced, and polaron delocalization increases. This is the first time such mechanisms are identified in doped‐OECTs and doped‐OMIECs. The work herein therefore takes the first steps toward developing the design guidelines needed to realize chemical doping as a generic strategy for tailoring performance metrics in OECTs and OMIECs. [ABSTRACT FROM AUTHOR]

Green‐processable printed large‐area light‐emitting diode (LED) is the crucial component of the high quality solid lighting and flat‐panel display. Accelerating the replacement from fossil‐based solvents to sustainable ecofriendly solvent is desirable for solution‐based printed organic electronics. Herein, by simple introducing methyl to the benzene groups of polydiarylfluorene‐based polymer, this work realizes the solution processing of blue polymer light‐emitting diodes (PLEDs) with a bio‐based solvent of limonene toward large‐area printed display. Film processed from this solvent exhibits satisfactory morphology and remarkable photophysical performances, even though the polymer chains show more serious aggregation in solution. What's more, devices fabricated with spin‐coated films present higher external quantum efficiency (EQE) and better spectra repeatability. Encouraged by the good film‐forming ability of this polymer in limonene, this work realizes the fabrication of printed large‐area films (5 × 5 cm2) with uniform emission and surface morphology by blade coating. Furthermore, this work develops passive matrix (PM) PLEDs arrays with 20 × 20 pixels that can dynamically display monochrome letters and numbers, demonstrating the potential application of cost‐effective printing techniques in large‐area display. [ABSTRACT FROM AUTHOR]

In organic electronics, conjugated conductive polymers are most widely used. The scope of their application is currently very wide. Non-conjugated polymers are used much less in electronics and are usually used as insulation materials or materials for capacitors. However, the potential of non-conjugated polymers is much wider, due to the fact that new electronic materials with unique electronic properties can be created on the basis of non-conjugated polymers, as well as other inorganic dielectrics. This article demonstrates the possibilities of creating electrically conductive materials with unique electronic parameters based on non-conjugated polymers. The results of the study of the sensory properties of humidity are given as examples of the practical application of the structure. The abnormal electronic properties are realized along the interface of two polymer dielectrics with functional polar groups. The submicron films of polydiphenylenephthalide were used as a dielectric. It is shown that a quasi-two-dimensional electronic structure with abnormally large values of conductivity and mobility of charge carriers occurs along the interface. These structures are often called quasi-two-dimensional electron gas (Q2DEG). This article describes the manufacturing processes of multielectrode devices. Polymer films are deposited via the spin-coating method with polymer solutions in cyclohexanone. The metal electrodes were manufactured through thermal deposition in a vacuum. Three types of metal electrodes made of aluminum, copper and chromium were used. The influence of the electron work function of contacting metals on the electronic parameters of the structure was studied. It was established that the work function decrease leads to an increase in the conductivity and mobility of charge carriers. The charge carrier parameters were estimated based on the analysis of the current-voltage characteristics within the space-charge-limited current technique. The Richardson-Schottky thermionic emission model was used to evaluate values a potential barrier at metal/organic interfaces. It was established that the change in ambient humidity strongly affects the electronic transport properties along the polymer/polymer interface. It is demonstrated that the increase in conductivity with an increase in humidity occurs due to an increase in the mobility of charge carriers and a decrease in the height of the potential barrier at the three-dimensional metal contact with two-dimensional polymer interface. The potential barrier between the electrode and the bulk of the polymer film is significantly higher than between the electrode and the quasi-two-dimensional polymer structure. [ABSTRACT FROM AUTHOR]

Melanins are a class of conjugated biopolymers with varying compositions and functions, which have a variety of potential medical and technical applications. Here, this work examines the conjugated polymers derived from a variety of phenolic monomers (catechol (CAT), levodopa (DOPA), and homogentisic acid (HGA)), using a selection of different analytical chemistry techniques to compare their properties with a view to understanding structure–function relations. The polymers display measurable conductivity, with electronic properties tuned by the functional groups pendant on the polymer backbones (which served as dopants) suggesting their potential for application in electronic devices. [ABSTRACT FROM AUTHOR]

While the Green‐Kubo and non‐equilibrium molecular dynamics methods have been compared quite extensively to calculate the thermal conductivity in inorganic compounds, there is currently a lack of comparison of these algorithms with the more recently developed approach‐to‐equilibrium molecular dynamics (AEMD) method for other types of materials such as organic semiconductors. To fill this gap, this article reports a theoretical description of thermal transport in single crystals made of terthiophene as prototypical system based on the three most popular molecular dynamics approaches. A systematic comparison of the computed values of thermal conductivity and its anisotropy is carried out and the strengths and weaknesses associated with each method are discussed. Although the three algorithms give essentially the same trends, this study points to the "AEMD" approach as the most suitable compromise between accuracy and computing cost. On the material aspects, the theoretical modeling yields an anisotropic character of the thermal transport in crystals whose out‐of‐plane thermal conductivity component is approximately twice larger than the in‐plane components. The AEMD approach is further used to investigate the influence of temperature on thermal transport in terthiophene. The trends are utterly rationalized by relying on the concepts of phonon mean free paths and phonon group velocities. [ABSTRACT FROM AUTHOR]

Hybrid films for applications in organic electronics from NiFe2O4 nanoparticles (NPs) in poly(3,4 ethylene dioxythiophene), poly(4-styrenesulfonate) (PEDOT:PSS), and poly(methyl methacrylate) (PMMA) were fabricated by the spin-coating technique. The films were characterized by infrared spectroscopy, atomic force microscopy, scanning electron microscopy, and energy-dispersive spectroscopy to subsequently determine their optical parameters. The electronic transport of the hybrid films was determined in bulk heterojunction devices. The presence of NiFe2O4 NPs reinforces mechanical properties and increases transmittance in the hybrid films; the PEDOT:PSS-NiFe2O4 NPs film is the one that has a maximum stress of 28 MPa and a Knoop hardness of 0.103, while the PMMA-NiFe2O4 NPs film has the highest transmittance of (87%). The Tauc band gap is in the range of 3.78–3.9 eV, and the Urbach energy is in the range of 0.24–0.33 eV. Regarding electrical behavior, the main effect is exerted by the matrix, although the current carried is of the same order of magnitude for the two devices: glass/ITO/polymer-NiFe2O4 NPs/Ag. NiFe2O4 NPs enhance the mechanical, optical, and electrical behavior of the hybrid films and can be used as semi-transparent anodes and as active layers. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Conjugated polymers (CPs) containing quinoidal units are promising in n‐type organic thermoelectric materials because of their deep‐positioned lowest unoccupied molecular orbital (LUMO) energy levels and planar conjugated backbones. Herein, three CPs have been synthesized by copolymerizing an indandione‐terminated quinoidal unit with bithiophene derivatives. Owning to the high electron affinity of the indandione‐terminated quinoidal unit, all polymers showed deep LUMO energy levels below –4.10 eV. Incorporating electron‐withdrawing substituents (F or CN) on the bithiophene comonomer can further downshift the LUMO energy levels. As a result, a more efficient n‐doping process can be realized when employing 4‐(2,3‐dihydro‐1,3‐dimethyl‐1H‐benzimidazol‐2‐ yl)‐N,N‐dimethylbenzenamine (N‐DMBI) as the dopant. Ultimately, the polymer with CN substituents delivered the best thermoelectric performance with a power factor of up to 2.14 μW·m−1·K−2, because it possessed the lowest LUMO energy level among the three CPs. This work highlights that the modulation of LUMO energy level is an effective strategy to optimize the thermoelectric performance of CPs. [ABSTRACT FROM AUTHOR]

Doping plays a critical role in organic electronics, and dopant design has been central in the development of functional and stable doping. In this study, there is departure from conventional molecular dopants and a new class of dopants are reported – aromatic ionic dopants (AIDs). AIDs consist of a pair of aromatic cation and anion that are responsible for molecular doping reaction and charge balancing separately. It is shown that the first AID made from cycloheptatrienyl (tropylium) cation and pentacyanocyclopentadienide anion (PCCp), abbreviated as T‐PCCp, can function as an effective p‐type dopant to dope polydioxythiophenes. Here, tropylium cation induces the doping reaction while the PCCp anion stabilizes the generated polarons and bipolarons. With T‐PCCp, a highly doped (≈120 S/cm) and stable system is achieved up to 150 °C, an orthogonal (sequential)solution processing resulting from the immiscibility of the dopant and the polymer host, and a high‐resolution direct micropatterning with laser writing resulted from a thermally activated doping process. [ABSTRACT FROM AUTHOR]

Organic electronic materials are starting to appear in various applications, but there are still hurdles to overcome before the average consumer can get them in their hands. Right now, most polymers in the field of organic electronics are made from petroleum derivatives. However, new sources of platform chemicals and monomers are being explored. This perspective article highlights ways that have been explored to avoid the use of petrochemicals and demonstrates new pathways that can be taken to increase the sustainability of conjugated polymers in organic electronics. [ABSTRACT FROM AUTHOR]

A grand challenge in materials science is to identify the impact of molecular composition and structure across a range of length scales on macroscopic properties. We demonstrate a unified experimental-theoretical framework that coordinates experimental measurements of mesoscale structure with molecular-level physical modeling to bridge multiple scales of physical behavior. Here we apply this framework to understand charge transport in a semiconducting polymer. Spatially-resolved nanodiffraction in a transmission electron microscope is combined with a self-consistent framework of the polymer chain statistics to yield a detailed picture of the polymer microstructure ranging from the molecular to device relevant scale. Using these data as inputs for charge transport calculations, the combined multiscale approach highlights the underrepresented role of defects in existing transport models. Short-range transport is shown to be more chaotic than is often pictured, with the drift velocity accounting for a small portion of overall charge motion. Local transport is sensitive to the alignment and geometry of polymer chains. At longer length scales, large domains and gradual grain boundaries funnel charges preferentially to certain regions, creating inhomogeneous charge distributions. While alignment generally improves mobility, these funneling effects negatively impact mobility. The microstructure is modified in silico to explore possible design rules, showing chain stiffness and alignment to be beneficial while local homogeneity has no positive effect. This combined approach creates a flexible and extensible pipeline for analyzing multiscale functional properties and a general strategy for extending the accesible length scales of experimental and theoretical probes by harnessing their combined strengths. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) is a widely used cathode interlayer material in inverted organic solar cells (OSCs). However, there are lots of surfaces or bulk film defects in ZnO layers, which degrade solar cell performance. Here, the typical phosphorylcholine‐ and sulfobetaine‐based polymer zwitterions (PMPC and PDMAPS) are synthesized via reversible addition‐fragmentation chain‐transfer (RAFT) polymerization to modify ZnO interlayers for inverted OSCs. The polymer zwitterions can efficiently passivate the defects in ZnO films and thus increase the conductivity of the ZnO interlayers. Both PMPC and PDMAPS modified ZnO interlayers show some general advantages in improving the performance of fullerene‐based and non‐fullerene‐based OSCs. The highest efficiency of 16.69% is achieved by using PMPC modified ZnO interlayers in PM6:Y6 based solar cell devices, which is among the best performance in inverted OSCs. Such an improvement in device performance is attributed to the work function reduction of the polymer zwitterions modified ZnO films, which provides an efficient cathode platform to extract and transport electrons from the active layers, to the benefit of suppressing interfacial charge recombination. As a result, the organic‐inorganic hybrid composites (ZnO: polymer zwitterions) show efficient interfacial modification to align energy levels at the device interface, which have promising application prospects in organic electronics. [ABSTRACT FROM AUTHOR]

This review article presents different electrochemical and spectroelectrochemical techniques used to investigate conjugated polymers. The development of this research area is presented from an over 40-year perspective—the period of research carried out by Professor Mieczyslaw Lapkowski. Initial research involved polymers derived from simple aromatic compounds, such as polyaniline. Since then, scientific advances in the field of conductive polymers have led to the development of so-called organic electronics. Electrochemical and spectroelectrochemical methods have a great influence in the development of organic semiconductors. Their potential for explaining many phenomena is discussed and the most relevant examples are provided. [ABSTRACT FROM AUTHOR]

Insulating polymers (commodity plastics in particular) are a major category of polymeric materials widely used in our daily life, but they exhibit abysmal electrical conductivity. Instead, conjugated polymers are gaining tremendous interest due to their excellent electrical properties and versatile applications in organic electronics. In this perspective, we provide a concise account of the added value in organic solar cells, as brought by the combined use of conjugated and insulating polymers. The challenging tasks and prospective directions are given to the potential benefits of employing insulating polymer additives, which spans from common commodity plastics to high-temperature resistant resins and thermoplastic elastomers. Particularly, the inert polymers can improve many important properties such as mechanical and thermal robustness but not sacrifice optoelectronic performance. [ABSTRACT FROM AUTHOR]

Fluorene is a well conjugated, planar, polycyclic aromatic organic compound that was first noticed, isolated, and purified by a French chemist, Marcellin Berthelot, in 1867. Since then, plenty of scientific investigators has spent years and decades understanding more about fluorene and its derivatives because of its high scope of applications in polymers, electronic devices, sensors, and photochromic materials. By considering the significance and novelty of the title molecule and the need for a concise assembly of its various synthetic methodologies, we tried to incorporate all the significant and recent developments and modifications regarding the synthesis of fluorenes. Here we portrayed various synthetic strategies to get different classes of fluorenes, including 9‐substituted fluorenes, spirofluorene‐based compounds, fluorenes with ring substitution, and fluorene‐based oligomers and polymers. The synthetic approaches for designing fluorene derivatives that are of high utility as well as environment friendly have been briefed in this review. [ABSTRACT FROM AUTHOR]

The field of organic semiconductors is multifaceted and the potentially suitable molecular compounds are very diverse. Representative examples include discotic liquid crystals, dye‐sensitized solar cells, conjugated polymers, and graphene‐based low‐dimensional materials. This huge variety not only represents enormous challenges for synthesis but also for theory, which aims at a comprehensive understanding and structuring of the plethora of possible compounds. Eventually computational methods should point to new, better materials, which have not yet been synthesized. In this perspective, it is shown that the answer to this question rests upon the delicate balance between computational efficiency and accuracy of the methods used in the virtual screening. To illustrate the fundamentals of virtual screening, chemical design of non‐fullerene acceptors, thermally activated delayed fluorescence emitters, and nanographenes are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Six polymers based on thiazolothiazole via metal-free reaction are synthesized. • Organic semiconductors are developed via eco-friendly and low-cost methods. • Promising efficiency of 15.3% is obtained in perovskite solar cells. The design of conjugated polymers with advanced properties is a significant task for the development of organic electronics. At the same time, it is important to pay attention to the methods of their synthesis, excluding toxic and expensive reagents, following the trends in sustainability. In this study, six thiazolothiazole-based conjugated polymers with thiophene, fluorene, phenylene, and benzodithiophene moieties were synthesized and thoroughly characterized. All materials were obtained through a non-catalyzed condensation reaction of carbonyl derivatives with rubeanic acid under ambient conditions. It is shown that the optoelectronic and electrophysical properties of polymers are suitable for their application in organic or hybrid electronic devices. The certain polymers are found to be promising hole-transport interlayer materials in perovskite solar cells, thus featuring the great potential of proposed methods of development of organic semiconductors. [ABSTRACT FROM AUTHOR]

• The exploration of internal OLED device structure and its working mechanism with significance of various layers of OLEDs. • A comprehensive discussion processible conjugated polymeric nanocomposite materials exhibit marked electrical and optical properties towards the interest for OLEDs applications. • The application of such polymeric nanocomposite materials is discussed with their success and failure towards their optical and electrical properties in making OLEDs. • Efficient fabrication techniques for high performance OLEDs. Organic light-emitting diodes (OLEDs) are one of the leading, promising technologies for eco-friendly lighting sources and vivid color display panels owing to their low operating voltage, fast switching, wide viewing angle, lightweight flexibility, etc. This review reports the various synthesis techniques for optimizing the OLED device performance using polymeric nanocomposites, which provide lighting and display. The internal OLED device structure and its working mechanism have also been reviewed. Some of the processible conjugated polymeric nanocomposite materials exhibit unique electrical and optical properties that are of interest for OLEDs applications. Nanoparticles with conjugated polymer matrix make polymer nanocomposite, and that composite is used as an active layer between the structures of optoelectronic devices like OLEDs. The application of such polymeric nanocomposite materials is discussed, as well as their success and failure regarding their optical and electrical properties in making OLEDs. Various OLED device fabrication technologies have been reported. The quantum leap of solid-state flexible and rollable lighting and display devices as of OLED applications is also discussed. The exploration encompasses various aspects, including synthesis methods, internal device structures, working mechanisms, and the fabrication technologies involved in OLEDs. The insights obtained will contribute to the advancement of sustainable lighting and display technologies, fostering innovation in the field of organic electronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • The organic semiconductor film is not uniform along the perpendicular direction. • The inhomogeneity of the film affects the mobility at different film-depth positions. • An approach was presented to study the mobilities at different film-depth positions. • The structure–property relations at different positions of the film were established. Carrier mobility is a crucial parameter characterizing the performance of organic semiconductors in thin film optoelectronic devices. The organic semiconductor film is usually not uniform along the film-perpendicular direction. This non-uniformity affects the carrier mobility at various depths within the film, thereby influencing device performance. Conventional methods for measuring mobility are basically not available to determine film-depth-dependent charge density or mobility. In this study, an easily accessed approach was proposed to investigate the film-depth-dependent electronic properties. Soft plasma etching was introduced to achieve incremental etching of the film, without causing damage to the underlying sublayers. For doped films with intrinsic charge, film-depth-dependent charge density, and film-depth-dependent mobility were extracted from the transfer characteristics evolution during the etching. For materials without intrinsic charge, film-depth-dependences of mobility could also be estimated under light illumination. The proposed method achieves a film-depth resolution of approximately 10 nm. It is revealed that for some model conjugated polymers, the mobility at the top surface is one order higher than that at the buried region of the transistor. This feature leads to unfavorable field-effect mobility. This work provides insights into the film-depth-dependent electronic properties and a strategy to optimize the electronic device performance. [ABSTRACT FROM AUTHOR]

Polymeric semiconductors based on donor-acceptor (D-A) conjugated polymers have emerged as a promising class of materials for various applications due to their excellent solution processability, low cost, and intrinsic flexibility. The use of the indacenodithiophene (IDT) unit as a building block has received significant attention due to its unique pentacyclic ring structure and exceptional photophysical and electronic properties. This review focuses on the latest progress in the field of IDT-based polymers. We discuss the versatility of IDT as a structural molecular engineering tool, along with the use of various electron-deficient acceptors as comonomers and modifications to the IDT structure unit. These advancements have led to improved device performance, particularly in organic electronics applications such as photodetectors, solar cells, field-effect transistors, and thermoelectric devices. In summary, this review serves as a valuable reference for researchers who are interested in creating high-performance polymeric semiconductors using the IDT building block for a range of optoelectronic devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) are widely used in various domains of organic electronics. However, the performance of organic electronic devices can be variable due to the lack of precise predictive control over the polymer microstructure. While the chemical structure of CPs is important, CP microstructure also plays an important role in determining the charge-transport, optical and mechanical properties suitable for a target device. Understanding the interplay between CP microstructure and the resulting properties, as well as predicting and targeting specific polymer morphologies, would allow current comprehension of organic electronic device performance to be improved and potentially enable more facile device optimization and fabrication. In this Feature Article, we highlight the importance of investigating CP microstructure, discuss previous developments in the field, and provide an overview of the key aspects of the CP microstructure-property relationship, carried out in our group over recent years. [ABSTRACT FROM AUTHOR]

The reproducibility issue is one of the major challenges for the commercialization of large‐area organic electronic devices. It involves both the device‐to‐device variation and opto‐electronic properties in different positions of a single thin film. Herein, the molecular weight effects in polymeric semiconductors with three widely used photovoltaic donor materials P3HT, PBDB‐T, and PM6 are systematically investigated. A simple but effective method is proposed to evaluate the uniformity of large‐area devices by adopting the micron‐level grid electrodes in organic thin films. An interesting phenomenon is observed that the device is gradually improved uniformly with the Mw range lower than 100 kg mol−1. In neat films, both the mobility and energetic disorder values of hole carriers exhibit relatively lower coefficient of variation (cv) in high molecular‐weight systems. After blending with the electron‐accepting materials, their bulk heterojunction films also enjoy more uniform hole transfer rates, fluorescence lifetimes, and power conversion efficiencies in single and different devices. This work not only proposes a facile approach to evaluate the electrical properties of large‐area organic thin films, but also demonstrates the relationship between molecular weight and device reproducibility in polymer solar cells. This contribution provides a new insight into the commercial large‐scale production of organic electronics. [ABSTRACT FROM AUTHOR]

Melanins are a class of biopolymers that are widespread in nature, with diverse origins, compositions, and functions, and their chemical and optoelectronic properties render them potentially useful for application in materials science for various biotechnological applications. For patients with alkaptonuria, the accumulation of homogentisic acid (HGA) in their bodies is associated with the concomitant deposition of pyomelanin, which is a pigment that contains significant amounts of polymerized HGA (polyHGA) in the bodily tissues of the patients. The polymerization of HGA under various different conditions in vitro is investigated using a selection of different analytical chemistry techniques to understand if there may be a correlation between the conditions and pigment deposition in vivo, and their potential for application as green/sustainable and components of electronic devices. [ABSTRACT FROM AUTHOR]

Donor–acceptor (D–A) conjugated polymers have gotten significant attention in the past decades. Wide application area, ease of production, and cost‐effectiveness have made the D–A conjugated polymers a pivotal class of organic electronics. Organic solar cells (OSCs) became one of the most critical application areas of conjugated polymers among many. Up to the last decade, intensive research has been conducted on fullerene‐based OSCs. Drawbacks of fullerene derivatives like high cost, production obstacles, and difficulties in modifying molecular structure made the academia seek new alternatives. Emerging nonfullerene acceptors (NFAs) draw a new path for academia to tune OSCs' power conversion efficiency (PCE). With the ease of synthesis and purification, modification of molecular structure via various functional groups, NFAs start outperforming fullerene‐based acceptors. Thieno[3,4‐c]pyrrole‐4,6‐dione (TPD) is widely used in D–A conjugated polymers for high‐performance OSCs. As a strong electron‐withdrawing group, TPD provides deepened lowest unoccupied molecular orbital energy level and wide bandgaps when introduced into polymer backbones, enhancing optoelectronic properties photovoltaic performance. Herein, an overview of the applications of TPD‐based donor and acceptor type conjugated polymers for nonfullerene and all‐polymer solar cells in the last 5 years is provided. [ABSTRACT FROM AUTHOR]

Curved X‐ray detectors have the potential to revolutionize diverse sectors due to benefits such as reduced image distortion and vignetting compared to their planar counterparts. While the use of inorganic semiconductors for curved detectors are restricted by their brittle nature, organic–inorganic hybrid semiconductors which incorporated bismuth oxide nanoparticles in an organic bulk heterojunction consisting of poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) and [6,6]‐phenyl C71 butyric acid methyl ester (PC70BM) are considered to be more promising in this regard. However, the influence of the P3HT molecular weight on the mechanical stability of curved, thick X‐ray detectors remains less well understood. Herein, high P3HT molecular weights (>40 kDa) are identified to allow increased intermolecular bonding and chain entanglements, resulting in X‐ray detectors that can be curved to a radius as low as 1.3 mm with low deviation in X‐ray response under 100 repeated bending cycles while maintaining an industry‐standard dark current of <1 pA mm−2 and a sensitivity of ≈ 0.17 μC Gy−1 cm−2. This study identifies a crucial missing link in the development of curved detectors, namely the importance of the molecular weight of the polymer semiconductors used. [ABSTRACT FROM AUTHOR]

Degradable organic semiconductors have significant potential for transient and biomedical organic electronics, but there have been only a few studies on fully degradable conjugated polymers (CPs) that achieve high electrical performance. In addition, these examples are limited to p‐type CPs. In this study, a series of fully degradable n‐type CPs, naphthalene diimide (NDI)‐based terpolymer (PNDIT2/IM‐f) are developed. The incorporation of an imine linker (IM) into the CP backbone affords the capability of facile hydrolysis degradation while maintaining efficient π‐conjugations and excellent electrical properties. An additional benefit of this molecular design is the systematic tunability of the degradation characteristics and electrical performance depending on the IM content (fIM). At the optimal point (fIM = 0.45) that enables complete degradation of the polymer under acidic conditions, the resulting PNDIT2/IM‐0.45 film exhibits high electron mobility (μe) of 0.04 cm2 V−1 s−1 in organic field‐effect transistors (OFETs), demonstrating excellent potential as transient OFETs. The high μe value is mainly attributed to the enlarged edge‐on orientations and tighter stacking of PNDIT2/IM‐f crystallites as increasing fIM. Thus, this study provides useful guidelines for the design of fully degradable n‐type CPs and establishes an important correlation between the molecular structure−electronic performance−transient properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • A metal-catalyst-free route to synthesize electrochromic CMP (E-CMP) is demonstrated. • The utilized method parallelly generates powder and film analogs of E-CMP. • The computational analysis suggests the formation of a 2D E-CMP framework. • The E-CMP registered a high coloration efficiency of ∼147 cm2/C at 650 nm. • The utilized E-CMP framework shows rich optical-memory features. Conjugated microporous polymers (CMPs) have gained rampant interest due to their remarkably well-suited features for organic electronics. However, little attention has been paid to the development of electrochromic CMPs (E-CMPs). To date, the synthesis of E-CMPs has only been reported through metal catalyst-based routes. Further, the inability of the reported routes to concurrently produce powder analogs (say, two-in-one approach) of the films has utterly restricted E-CMP's utilization in tools (such as adsorption analyzers and TEM) widely employed for the investigation of microporous nature. Due to this limitation, while successful synthesis of E-CMPs has been claimed in reports, the confirmation of their microporous nature still appears to be side-lined. Herein, we report a memory-rich conjugated microporous polymer-based electrochromic framework (denoted as E-CMP-Sb1) through a two-in-one metal-catalyst free route. The synthesized E-CMP-Sb1 film demonstrated good optical tunability in visible and NIR regions and registered a coloration efficiency of ∼147 cm2/C at 650 nm. The synthesized E-CMP-Sb1 was deployed in a gel-polymer electrolyte-based electrochromic device (ECD) to mark the first inching effort toward the still-unexplored field of E-CMP-based ECDs. Probing E-CMP's performance in real ECDs is expected to elucidate their commercial suitability in the years to come. This work provides a versatile platform for the existing synthesis and characterization issues of E-CMPs. Parallelly, the study also introduces a new material in the electrochromic fraternity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Six D-A conjugated polymers synthesized successfully in a continuous flow reactor. • Obtained high degree of polymerization (31 – 88) and excellent reproducibility. • High quality polymers synthesized using a single set of reaction parameters. • Flow synthesis as an ideal method to produce D-A conjugated polymers. Donor-acceptor (D-A) conjugated polymers often exhibit excellent performance in electronic and photonic applications, however, their synthesis remains a hurdle to achieving their wide-spread commercialization. While scalable and reproducible flow syntheses have emerged as promising candidates to address this issue, they have only been applied to a narrow scope of polymer types. In this study, we explore the synthesis of six different D-A conjugated polymers in a continuous flow reactor to determine how reaction and polymer parameters influence the degree of polymerization (DP) and quality of the resulting polymers. We found that we could successfully synthesize p -type, n -type, and ambipolar D-A conjugated polymers with a single set of reaction parameters. Only the reaction time required optimization to achieve high-DPs. Importantly, we found that we could achieve comparable DPs to batch reactions, but with higher yields and much shorter reaction times. High-quality polymers were also obtained, which was confirmed with optical and electrochemical properties measurements and by their performance in organic field-effect transistors. We expect this work to further establish flow synthesis as an ideal method to make D-A conjugated polymers, which may help facilitate their commercialization in high-performing organic devices. [ABSTRACT FROM AUTHOR]

Conjugated polymers are an important class of chromophores for optoelectronic devices. Understanding and controlling their excited state properties, in particular, radiative and non‐radiative recombination processes are among the greatest challenges that must be overcome. We report the synthesis and characterization of a molecularly encapsulated naphthalene diimide‐based polymer, one of the most successfully used motifs, and explore its structural and optical properties. The molecular encapsulation enables a detailed understanding of the effect of interpolymer interactions. We reveal that the non‐encapsulated analogue P(NDI‐2OD‐T) undergoes aggregation enhanced emission; an effect that is suppressed upon encapsulation due to an increasing π‐interchain stacking distance. This suggests that decreasing π‐stacking distances may be an attractive method to enhance the radiative properties of conjugated polymers in contrast to the current paradigm where it is viewed as a source of optical quenching. [ABSTRACT FROM AUTHOR]

Conjugated polymers are an important class of chromophores for optoelectronic devices. Understanding and controlling their excited state properties, in particular, radiative and non‐radiative recombination processes are among the greatest challenges that must be overcome. We report the synthesis and characterization of a molecularly encapsulated naphthalene diimide‐based polymer, one of the most successfully used motifs, and explore its structural and optical properties. The molecular encapsulation enables a detailed understanding of the effect of interpolymer interactions. We reveal that the non‐encapsulated analogue P(NDI‐2OD‐T) undergoes aggregation enhanced emission; an effect that is suppressed upon encapsulation due to an increasing π‐interchain stacking distance. This suggests that decreasing π‐stacking distances may be an attractive method to enhance the radiative properties of conjugated polymers in contrast to the current paradigm where it is viewed as a source of optical quenching. [ABSTRACT FROM AUTHOR]

Conjugated microporous polymers (CMPs) are a unique class of porous materials that have an integrated π‐conjugated system and permanent intrinsic porosity. They are of great interest because of their outstanding performance in gas sorption, photoredox catalysis, energy storage, organic light‐emitting diodes (OLEDs), and sensing applications. However, conventional chemically synthesized CMPs are solid powders and have poor solubility, which makes it difficult to process and integrate devices, and has become a bottleneck preventing their practical applications. Electropolymerization (EP) is a simple and efficient method for the preparation of CMP films, which simultaneously completes material synthesis and film processing. More importantly, the microstructure of the CMP films can be effectively controlled by electrochemical parameters. In this review, first, the basic synthetic principles and strategies of CMP films via EP are introduced, allowing for facile optimization of the structure and properties. Then, the recent progress of the EP CMP films is focused upon in organic electronics, energy storage, sensors, chemical capture and separation, and electrocatalysts. Finally, the challenges and outlook for EP CMP films are addressed. [ABSTRACT FROM AUTHOR]