The construction of complex superlattices using homogenous soft matter has great potential for the bottom-up fabrication of complex, nanoscale structures. This topic is not only interested in scientific exploring for new concepts of supramolecular crystals with nanometer in sizes, which is about thousand times larger in volumes than those of normal crystals, but also practically important to provide construction principles of metamaterials which are artificially structured materials for controlling and manipulating light, sound, and other physical behaviors. These systems have fast assembly kinetics and convenient processing procedures, making them ideal for large-scale superlattice production. In this perspective, we focus on recent developments in the construction of complex spherical packing superlattices using homogenous soft self-assemblies. We discuss the general mechanism of those formations of supramolecular motifs and provide an overview of the spherical packing superlattices self-assembled by homogenous soft matters based on different volume asymmetry. Additionally, we outline the potentials of utilizing this approach in constructing novel superlattices as well as its future challenges.

Electrodeposition is an old and effective method for the fabrication of organic films. Though electrodeposited organic films have been widely used in various applications, highly luminescent films have been a great challenge because the electrochemically doped state may strongly quench the fluorescence. In the first part of this review, the organic electrodeposition techniques, along with general electropolymerization and other special electrodepositions are introduced. In the second part of the review, we describe how to electrochemically fabricate luminescent films for organic light-emitting diodes (OLEDs). With the rational molecular design and well-controlled electrodeposition process, we have not only demonstrated high-performance OLEDs, but also paved a promising way to practice active-matrix OLEDs (AMOLEDs) and super-resolution OLEDs. In particular, RGB 3 × 3 array OLEDs based on active-matrix substrates, RGB passive-matrix OLEDs (PMOLEDs) with a resolution of 210 ppi, and monochromatic OLEDs with a super-resolution of 2822 ppi have been successfully fabricated. It is highly anticipated that the organic electrodeposition technology is of comparable or perhaps even higher contenders in manufacturing and downscaling OLEDs and AMOLEDs with low-cost and high-resolution for the human-computer interaction fields such as augmented reality (AR), virtual reality (VR),etc.

The recent progress in the design and synthesis of high-performance donor-acceptor conjugated polymeric semiconducting materials is reviewed from the perspective of multiscale structures. The multiscale of conjugated polymers is from the primary one-dimensional polymer molecular scale to the secondary polymer-chains interaction scale, and then to the tertiary polymer aggregate scale. This review focuses on the design and synthesis of polymer molecules, proposes new classification rules, and rationally summarizes the design strategies and modulation methods of polymers. We describe the recent progress from these three aspects: (1) the modification ofπ-conjugated backbone, (2) the evolution of the polymerization methods, and (3) the regulation of aggregate-state structure.

Since the first report of diketopyrrolopyrrole (DPP)-based conjugated polymers for organic thin-film transistors (OTFTs), these polymers have attracted great attention as representative semiconductors in high-performance OTFTs. Through unremitting efforts in molecular-structure regulation and device optimization, significant mobilities exceeding 10 cm²·V^–1·s^–1have been achieved in OTFTs, greatly promoting the applied development of organic circuits. In this review, we summarize our progress in molecular design, synthesis and solution-processing of DPP-based conjugated polymers for OTFT devices and circuits, focusing on the roles of design strategies, synthesis methods and processing techniques. Furthermore, the remaining issues and future outlook in the field are briefly discussed.

The translocation of a polymer through a pore that is much smaller than its size is a fundamental and actively researched topic in polymer physics. An understanding of the principles governing polymer translocation provides important guidance for various practical applications, such as the separation and purification of polymers, nanopore-based single-molecule deoxyribonucleic acid/ribonucleic acid(DNA/RNA) sequencing, transmembrane transport of DNA or RNA, and infection of bacterial cells by bacteriophages. The past several decades have seen great progresses on the study of polymer translocation. Here we present an overview of theoretical, experimental, and simulational stduies on polymer translocation, focusing on the roles played by several important factors, including initial polymer conformations, external fields, polymer topology and architectures, and confinement degree. We highlight the physical mechanisms of different types of polymer translocations, and the main controversies about the basic rules of translocation dynamics. We compare and contrast the behaviors of force-induced versus flow-induced translocations and the effects of unknotted versus knotted polymers. Finally, we mention several opportunities and challenges in the study of polymer translocation.

Although photothermal therapy (PTT) has been developed for fighting cancers, the degradative, toxic, and metabolic nature of photothermal conversion materials (PCMs) has prevented them from being clinically implemented. Taking advantage of the surface modification strategy of mussel-inspired dopamine chemistry and its excellent photothermal conversion effect, polydopamine (Pdop) represents a versatile PTT platform, providing strategies and methods for the construction of novel Pdop-functionalized PCMs. Thanks to its adhesion and secondary reactivity, Pdop can be deposited on virtually all substrates to improve their bioavailability and biocompatibility. Pdop-based PCMs could not be only functionalized with small biomoleculesviachemical bonds and/or noncovalent force but also modified with functional polymersviaeither the “grafting to” or “grafting from” method. This review highlights the synthetic methods, therapeutic strategies, and designs of PCMs based on Pdop in recent years to explore its scope and limitations.

We report herein the cationic polymerization of isobutylene (IB) under mild conditions is realized with a new binary initiation system generated by simply mixing a Lewis super acid Al(C₆F₅)₃and a substituted phenol (^RPhOH). Polymers with medium and/or high molecular weights (M_w=4.9×10⁴−27.7×10⁴g·mol⁻¹) can be obtained in toluene and temperatures from −20 °C to 0 °C. NMR spectrum analysis and DFT simulation reveals thein situgenerated acidic coordinating complexAl(C₆F₅)₃·^RPhOHis the initiating active species, which further transformed into the ion-pair[Al(C₆F₅)₃O^RPh]⁻[PIB]⁺of the active intermediates upon growing IB monomers where the counter anion[Al(C₆F₅)₃^ROPh]⁻coordinates to the macrocationviathe phenoxy oxygen. The catalyst performances are the concert effects of the steric bulkiness and electronics of the counter anion on the coordinating strength to the macrocation, which is significant to the stability of the active species.

Through neodymium-mediated coordinative chain transfer copolymerizaiton (CCTcoP), polyisoprenes bearing dual hydroxylated mini-blocky chain-ends were preparedviaa three-step strategy. Kinetic studies revealed that, the polymerization demonstrated typical features of CCTcoP across the whole polymerization process,i.e., quasi-living polymerization characteristic, tunable molecular weights, narrow molecular weight distributions, and atom economies. Comparing to previously reported CCTP homopolymerization systems, the presence of oxygen-containing Ip_OAlpolar comonomer slowed down chain transfer rates obviously, rendering slightly higher molecular weights of the resultant PIps and smallerN_p(number of polymer chains per Nd atom) values. Moreover, to mimic the structure of natural rubber, the hydroxyl end groups can be facilely modified into phosphonate, amide, and UPy, whose structures were further confirmed by NMR spectra. Incorporation these functionalities could greatly improve the hydrophilic properties of the polymers, as revealed from the significantly reduced static water contact angles.

Aliphatic polyamides have been considered as eco-friendly materials, useful for a wide range of applications. However, it still presents obstacle to produce sustainable aliphatic polyamides from abundant renewable sources. Herein, we describe that 4-hydroxyproline (4-HYP), a renewable resource, was readily converted to its corresponding bicyclic bridged lactam monomers bearing pendant Boc-protected secondary amino group, and oligo-ethylene glycol group. Lithium hexamethyldisilazide (LiHMDS)-mediated polymerization of the resulting monomers exhibited a controlled feature, affording sustainable aliphatic polyamides with number-average molecular weight up to 73 kg/mol and a low molecular weight distributionĐ<1.28. Overall, this work can lead to a novel kind of functional and sustainable polyamides with potential applications, including degradable plastics, and drug delivery.

Well-defined polycarbonate diol was successfully synthesized through a strategy using a combination of organocatalyst and water. Such strategy was less developed in organocatalyzed polymerization and frequently regarded as side reactions. Herein, one-component phosphonium borane Lewis pairsPB1−PB8were successfully applied in the copolymerization of CO₂and cyclohexene oxide (CHO) to generate poly(CHO-alt-CO₂) carbonate (PCHC). Parameters of linker length and counter anion effects on the catalyst activity were investigated. It was found that Lewis pairPB3served as a dual initiator and catalyst in the copolymerization of CHO and CO₂with or without the presence of water. In contrast, Lewis pairPB8can serve as a true catalyst for the preparation of well-definedα,ω-hydroxyl PCHC diols. This was achieved by introducing a labile CF₃COO group as counter anion through anion exchange reaction while water molecules acted as chain transfer agents. The function of trifluoroacetate group in the polymerization process was investigated in detail and possible mechanism was proposed. Upon changing the amount of water and catalyst loading, PCHC diols with varied molecular weight (1.5 kg/mol to 7.5 kg/mol), low dispersities (Ð<1.2) and carbonate content (>99%) could be easily obtained. The low molecular weight PCHC diol was used as a bifunctional macroinitiator for the ring-opening polymerization of L-lactide (LLA) to afford ABA triblock copolymer in one-pot synthesis.

Coordination-insertion ring-opening polymerization (ROP) of cyclic esters is an industrial way to synthesize polyesters, which are widely applied in biomedical and environment-benign fields. However, the rate-determining transition state (TS) identified by the conventional reaction pathways (pathway A and pathway B) presented in the literature did not well describe the structure-reactivity relationship. The misidentification of the rate-determining TS might arise from the less ergodicity in the search of reaction pathways. Herein, we suggested a stride strategy based on the insight that even a partial double bond is rotatable at the catalysis temperature. As a result, we revealed a new reaction pathway, pathway C with a torsion transition state TSC2, by density functional theory (DFT). We also carried out kinetic experiments of ROP of D-lactide (D-LA), L-lactide (L-LA),ε-caprolactone (CL), andδ-valerolactone (VL), using poly(ethylene glycol) as the initiator and stannous octoate as the catalyst. The excellent linearity between the calculated free energy barriers and logarithms of the experimental kinetic constants of the two kinds of lactide and lactone monomers, was established, validating the quasi-ergodic search of reaction pathways and the scaling predicted by transition state theory. The linearity was highly predictive for the other lactide and lactone monomers, demonstrated by glycolide (GA) and trimethylene urethane (TU).

Achieving the linear polymers with high molecular weightviastep-growth polymerization of A₂and B₂monomers is significantly limited by the requirement of strict stoichiometry of two monomers when the reactivity of A and B groups are not changed during the polymerization. Herein, a unique step-growth polymerization based on copper-catalyzed azide-alkyne cycloaddition (CuAAC) with reaction-enhanced reactivity of intermediate (RERI) mechanism was developed for the preparation of mainchain semifluorinated polymers with high molecular weight. The CuAAC polymerization of bis-alkynyl-terminated fluorinated monomers (A₂) and 2,2-bis(azidomethyl)propane-1,3-diyl bis(2-methylpropanoate) (BiAz, B₂) with RERI effect at different stoichiometric ratio was systematically investigated. The results indicated that the semifluorinated polymers with ultrahigh molecular weight,M_w,MALLS>10⁶g/mol, could be efficiently synthesized by using excess molar of BiAz monomers. The resultant high-molecular-weight semifluorinated polymers show good thermostability and high hydrophobicity. In addition, the glass transition temperature (T_g) of these mainchain semifluorinated polymers could be tuned conveniently due to the bis-alkynyl-terminated comonomers could be consumed completely when excessive BiAz monomers were used in this this step-growth polymerization.

Compared with spherical micelles, rod/worm-like micelles not only have extended blood circulation duration, but also exhibit favorable cellular uptake behavior, which is promising for next-generation nanomedicine and biomaterials. However, the controllable fabrication of narrowly dispersed nanorods in aqueous media is still challenging. Herein, the methodology of thermal annealing was developed for the fabrication of helical nanorods as well as a series of nanorods with different lengths. The thermal annealing process generally consisted of adding a percentage of organic solvent (10%(V/V) or 20%(V/V)) to the digital micellar aqueous dispersion, followed by heating at 90 °C for 1 h, then cooling naturally to room temperature, and dialyzing against water to remove the organic solvent. Right-handed helical nanorods were afforded by the treatment of 45 nm digital micelles in the presence of 10%(V/V) dioxane, while left-handed helical nanorods were obtained in the presence of 20%(V/V) dioxane. Meanwhile, the controlled growth of rod-like digital micelles was achieved after thermal annealing in the presence of different types of organic solvents, and the length of the annealed nanorods was correlated with the types of organic solvent. Furthermore, no matter the size of initial digital micelles, they all exhibited similar trend of rod growth in the presence of a certain amount of organic solvent, allowing for controllable formulation of narrowly dispersed nanorods. In addition, supramolecular self-assembly by amphiphilic dendritic oligourethane readily fabricated diverse uniform nanorods in aqueous media. Overall, this work provided an attractive methodology to fabricate uniform digital nanorods.

The effect of freezing layer on the crystallization kinetics of poly(ε-caprolactone) (PCL) thin and ultrathin films was investigated by monitor the growth process of it on oriented polyethylene (PE) and CaF₂with and without freezing layer, respectively. It was found that the PCL films with similar thicknesses crystallize much faster on oriented PE than on CaF₂substrate. For example, the crystallization rate constant of a 102 nm thick PCL film decreases tremendously by 3 orders of magnitude from 1.1×10⁻¹on PE substrate at 50 °C to 7×10⁻⁴on CaF₂surface at 40 °C. Moreover, the crystallization of PCL accelerates on CaF₂surface while slows down at PE surface with increasing film thickness. The ultrathin films of PCL with thickness less than 14 nm exhibits the fastest crystallization rate on oriented PE with a rate constant of about 3.5×10⁻¹, which is 3 times higher than that of aca. 50 nm thick film. This illustrates the great influence of freezing layer on the crystallization process of PCL. The freezing layer thickness of PCL on PE is estimated to be in the range of 14−17 nm. Taking the radius of gyration (R_g~ 15.6 nm) of the used PCL material into account, the obtained results may imply the existence of a correlation between theR_gof PCL and its freezing layer thickness at PE substrate.

Shape control of mesoporous carbon microparticles (MCMPs) is of critical importance; in particular, asymmetric shapes that can yield unique properties have attracted significant attention. However, the tailored synthesis of asymmetric MCMPs with ordered structures remains challenging. Herein, we report a facile route to prepare asymmetric MCMPs by dynamic neutral interface-guided 3D-confined self-assembly (3D-CSA) of block copolymer/homopolymer (BCP/hP) blends, followed by a self-templated selective direct carbonization strategy. BCP/hP Janus microparticles with ordered hierarchical mesostructures were prepared with emulsion solvent evaporation-induced 3D-CSA. The continuous phase of BCP domains was then crosslinked. Composite asymmetric MCMPs are successfully generated after selective carbonization of the crosslinked continuous phase. This method allows tuning the shape of MCMPs easily by varying the blending ratio of BCP/hP. The composite asymmetric MCMPs combine the advantages of asymmetric shape, ordered structure, high specific surface area, chemical inertness and thermal stability and could provide great possibilities for applications in catalysis, drug delivery, energy conversion and storage.

Two new ratiometric hypoxia probes (Ir-C343 and Ir-GFP) are synthesized by covalently incorporating florescent internal standard molecules coumarin 343 (C343) and green fluorescent protein (GFP) into bis[1-(9,9-dimethyl-9H-fluoren-2-yl)-isoquinoline] (succinylacetone) Ir(III) (Ir-fliq), respectively. After connecting with internal standard molecules, the Ir-fliq moiety still exhibits high sensitivity to oxygen concentration, while the fluorescence intensity of the internal standard remains relatively constant under different oxygen concentrations. As a result, a ratiometric response is realized that is only related to oxygen concentration. In addition, Ir-GFP shows more promising applications in the ratiometric hypoxia imaging of cells due to its long excitation wavelength, good water solubility, high biocompatibility, and low relative fluorescence intensity compared with the phosphorescent emitter Ir-fliq.

Three carbazole-based multiple resonance dendrimers namely D1-BNN, D2-BNN and D3-BNN, are developed for solution-processed narrowband blue organic light-emitting diodes (OLEDs) by introducing the first-, second-, and third-generation carbazole dendrons in periphery of boron, nitrogen-doped polycyclic aromatic hydrocarbon skeleton. Different from D1-BNN containing first-generation carbazole dendron showing moderate photoluminescent quantum efficiency (PLQY) of 68% in solid state and broadened emission bands with full-width at half maximum (FWHM) increasing from 26 nm to 34 nm upon doping concentration growing from 10 wt% to 40 wt%, D3-BNN with the third-generation carbazole dendron exhibits high PLQY of 92% and weak dependence of photoluminescent spectra on doping concentration, which can remain narrowband emissions with unchanged FWHM of 24 nm at same doping concentration range. Solution-processed OLEDs employing D3-BNN as emitter reveal blue electroluminescence at 477 nm with FWHM of 24 nm, and maximum external quantum efficiency (EQE) of 17.3% which is kept at 14.4% at doping concentration of 40 wt%, much superior than the D1-BNN devices showing maximum EQE of 13.0% that drops to 3.7% at 40 wt% doping concentration.

Molecular doping is one of the most important tools to manipulate the electrical properties of conjugated polymers for application in organic optoelectronics. The polymer crystallinity and distribution position of the dopant crucially determine electrical conductivity of the doped polymer. However, in solution-mixed doping, the interplay between polymer and dopant leads to highly structural disorder of polymer and random arrangement of dopant. Here, we propose a strategy to ensure the dopant induced polarons have high charge dissociation and transport by letting the conjugated polymers aggregate in the marginal solvent solution by cooling it from higher temperature to room temperature. We select poly(3-hexylthiophene-2,5-diyl) (P3HT) solution doped by 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) as a model system. P3HT crystallizes in the marginal solvent, such as 1,1,2-trichloroethane (TCE) driven by the favorπ-πinteraction between planar polymer backbone. The dopant F4TCNQ enters the alkyl side chain region not theπ-πstacking region and thus guarantees high crystallinity and theπ-πinteraction of P3HT. This distribution of F4TCNQ which away from the polymer backbone to ensure higher charge dissociation and transport. Finally, we obtained a high conductivity value of 23 S/cm by doping P3HT with 20% F4TCNQ by using the marginal solvent, which is higher than doping P3HT with a disordered coil conformation in chlorobenzene (CB) of 7 S/cm, which the dopants enter both the alkyl side chain region and theπ-πstacking region.

The solubility of a direct arylation polycondensation (DArP) synthesized conjugated polymer,i.e., poly(3,6-bis(furan-2-yl)-2,5-bis(4-tetradecyloctadecyl)-pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione-alt-1,2-bis(3,4-difluorothien-2-yl)ethene) (PFuDPP-4FTVT), in various organic solvents was studied. The polymer is soluble in 3-methylcyclohexanone (3-MC), a green solvent from peppermint oil, besides other solvents such as anisole, cyclopentyl methyl ether (CPME) ando-dichlorobenzene (o-DCB),etc. Based on the Hansen solubility parameters (HSP) analysis, 3-MC is identified as a “marginal solvent” of PFuDPP-4FTVT. The morphology of the spin-coated films with 3-MC as the solvent strongly correlated with the solution preparation conditions. With a 3-MC solution aged for 3 h at 70 °C, n-channel organic thin-film transistors (OTFTs) with electron mobility (μ_e) above 1 cm²·V⁻¹·s⁻¹and current on/off ratio (I_on/I_off) higher than 10⁵were fabricated by spin-coating. This is the first report on high mobility conjugated polymers for OTFTs processible with naturally occurred green solvent.

The development of donor-acceptor (D-A) type conjugated polymers depends largely on the design of novel A building blocks. Herein, we report a novel A building block based on the cyano-substituted organoboron unit (SBN-3). Compared with the most common fluorine-substituted B←N unit,SBN-3displays a significantly downshifted LUMO energy level because of the strong electron-withdrawing ability of cyano groups. In addition, due to the greater impact of cyano substitution on LUMO than on HOMO,SBN-3exhibits a reduced band gap, near-infrared absorption and fluorescence properties. The D-A type conjugated polymers based on the cyano-substituted B←N unit with thiophene-based units show narrow optical band gaps ofca. 1.3 eV as well as distinctive electronic structures,i.e., delocalized LUMOs and localized HOMOs. This work thus provides not only an effective approach to design strong A units but also a new electron-deficient building block for D-A type conjugated polymers.