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Conductive polymer hydrogels exhibit unique electrical, electrochemical, and mechanical properties, making them highly competitive electrode materials for stretchable high‐capacity energy storage devices for cutting‐edge wearable electronics. However, it remains extremely challenging to simultaneously achieve large mechanical stretchability, high electrical conductivity, and excellent electrochemical properties in conductive polymer hydrogels because introducing soft insulating networks for improving stretchability inevitably deteriorates the connectivity of rigid conductive domain and decreases the conductivity and electrochemical activity. This work proposes a distinct confinement self‐assembly and multiple crosslinking strategy to develop a new type of organic–inorganic hybrid conductive hydrogels with biphase interpenetrating cross‐linked networks. The hydrogels simultaneously exhibit high conductivity (2000 S m−1), large stretchability (200%), and high electrochemical activity, outperforming existing conductive hydrogels. The inherent mechanisms for the unparalleled comprehensive performances are thoroughly investigated. Elastic all‐hydrogel supercapacitors are prepared based on the hydrogels, showing high specific capacitance (212.5 mF cm−2), excellent energy density (18.89 µWh cm−2), and large deformability. Moreover, flexible self‐powered luminescent integrated systems are constructed based on the supercapacitors, which can spontaneously shine anytime and anywhere without extra power. This work provides new insights and feasible avenues for developing high‐performance stretchable electrode materials and energy storage devices for wearable electronics. [ABSTRACT FROM AUTHOR]

Smart responsive organic emitters, which exhibit tunable emission properties in response to external stimuli, can serve as a new generation of intelligent optoelectronic materials because of their versatile applications, such as multicolor displays, information encryption, visual sensing, and matter detection. In recent years, significant advancements have been made in the development of smart responsive organic emitters. However, there is still a lack of a systematic review that provides a comprehensive insight into smart responsive organic emitters from the perspectives of intrinsic mechanisms and versatile applications. Hence, this review concentrates on analyzing the intrinsic mechanisms, which can clarify the relationships between material systems and tunable emission behaviors. This process can provide helpful design principles for smart responsive organic emitters. Furthermore, versatile smart applications have been highlighted to deepen the understanding of the practical values of such smart responsive emitters. This work summarizes the state‐of‐the‐art progress of smart responsive emitters and highlights the existing challenges and future development directions. It aims to provide inspiration and guidelines for the construction of novel smart responsive organic emitters, thereby broadening and stimulating their prominent applications in various fields such as electronic information and flexible electronics. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in lithium ion batteries (LIBs). Despite recent advances, low ion conductivity and low transference number, resulting in low charging/discharging rate, low energy density, and short battery life, are the main issues that limit their direct application as solid electrolytes in LIBs. Here, we designed and synthesized a novel polyimide COF, namely, TAPA-PDI-COF, with abundant C=O groups, which has been successfully employed as high-performance solid electrolytes by doping TAPA-PDI-COF and succinonitrile (SN). Both the well-defined nanochannels of COFs and SN confined in the well-aligned channels restricted the free migration of anions, while C=O on COFs and CN groups of SN enhanced Li+ transport, thus achieving a high ion conductivity of 0.102 mS cm−1 at 80 °C and a high lithium-ion transference number of 0.855 at room temperature. According to density functional theory (DFT) calculations, Li-ion migration mainly adopted in-plane transport rather than the axial pathway, which may be due to the shorter hopping distances in the planar pathway. The results suggest an effective strategy for the design and development of all-solid-state ionic conductors for achieving high-performance LIBs. [ABSTRACT FROM AUTHOR]

Camouflage skin holds immense potential for a variety of advanced applications, such as artificial intelligence, soft robotics, and flexible/wearable electronics. Currently, most existing materials for constructing camouflage skin are mainly based on inorganic materials with an inverse opal scaffold, which significantly limits their further development because of the poor mechanical properties and environmental instability. Inspired by rana slvaticas, a new type of camouflage skin based on one‐dimentional (1D) photonic crystal (PC) gel is designed and synthesized, which combines the advantages of 1D PC structures with 3D flexible gels in a single skin device. Taking advantage of the unique structures, the resulting camouflage skins demonstrated attractive properties, including excellent mechanical performance, self‐adaptive camouflage capabilities, and long‐term stability in ambient conditions. Specifically, the camouflage skin can quickly recognize and match the background by modulating the optical signals of external stimuli. The synergistic effect of the glycerol, the dodecyl glycerol itaconate (DGI), and the nano‐space structures altogether contribute to the outstanding long‐term environmental stability of the camouflage skin. Overall, by combining the bio‐inspired concept and molecular engineering strategy, camouflage skin based on PC gels is synthesized, which greatly enriched the application and development in the smart skins field. [ABSTRACT FROM AUTHOR]

Replacing liquid electrolytes with solid‐state polymer electrolytes (SPEs) can solve the safety hazards of Li metal batteries (LMBs) while increasing their energy density. However, there has been limited success so far in preparing advanced SPEs with controllable molecular structure and chemical composition, posing great obstacles to further promoting its application in LMBs. Recently, ring‐opening polymerization (ROP), including cationic ROP, anionic ROP, and ring‐opening metathesis polymerization, has become a dazzling new star in achieving SPEs due to its mild polymerization conditions and controllable chemical composition (molecular structure, functional group), etc. Besides, there is no small molecule released during the polymerization process, which means reduced interfacial side reaction. Hence, in this review, the merits of ROP in preparing SPEs and its mechanism as well as interfering factors, etc are evaluated from the perspective of synthetic chemistry. Furthermore, the review focuses on outlining the existing cases related to ROP as much as possible and summarize them from different ring structures (from triple ring to multivariate ring) and polymerization methods, hoping to provide a comprehensive understanding and serve as strategic guidance for designing high‐performance SPEs. Challenges and opportunities regarding this burgeoning field are also discussed at the end. [ABSTRACT FROM AUTHOR]

Here, inspired by the unique mesh geometry of fishing nets and the knotted fiber structures that can simultaneously enhance both the strength and deformability of the materials, new crosslinkers and elastic components into the polyzwitterionic electrolytes to construct high‐strength and ultra‐flexible fishing‐net‐like structure electrolytes are introduced. Specifically, the crosslinker rich in –NH can not only form chemical crosslinking points between polyzwitterion and elastic segments, but also physical crosslinking points, resulting in high strength of the electrolytes. Additionally, the elastic segments provide the electrolytes with super flexibility, strongly reducing the interface resistance of devices. Moreover, the backbone of polymers can collectively regulate anions and Li+, realizing stable Li+ deposition and suppressing the growth of lithium dendrites. As a consequence, the Li||Li symmetric cell can be stably cycled at 0.1 mA h−1 for over 5500 h at 30 °C, and the assembled Li/LiFePO4 (LFP) and Li/ LiNi0.8Co0.1M0.1 (NCM 811) cells both show good cell performances at various C‐rates at 30 °C. This work provides a new perspective for the construction of polymer electrolytes with synergistic cation–anion regulation functions for high safety and high energy density solid‐state lithium batteries. [ABSTRACT FROM AUTHOR]

The performance of organic light emitting devices (OLEDs) fabricated using Ir(III) complexes bearing 1,3,4-oxadiazole (OXD)-based cyclometallic ligands still needs to be improved. In this work, Ir3+ was coordinated with a 2-(9,9-diethyl-9H-fluoren-2-yl)-1,3,4-oxadiazole (F-OXD) fragment, which was modified with various functionalized substituents, including fluorenyl, OXD and carbazolyl groups. Three complexes, named Ir-Flu, Ir-OXD and Ir-Cz, were synthesized successfully and their photophysical, electrochemical and electroluminescence properties were investigated in detail. All these complexes exhibited yellow-orange emission in solution and a distinct aggregation-induced phosphorescent emission (AIPE) phenomenon was observed. Monochrome OLEDs were fabricated using these phosphorescent dopants, and the turn-on voltage (V), luminance (L) and current efficiency (CE) showed significant improvement compared to analogous OXD-based Ir(III) complexes reported before. In particular, the device with Ir-OXD as the dopant achieved the highest maximum brightness of 25 014 cd m−2 and the lowest efficiency roll-off (42.6%) at the maximum luminance among all the devices. These results provided a proven strategy of functionalized decoration of OXD-based complexes to achieve superior luminous efficiency devices. [ABSTRACT FROM AUTHOR]

By investigating a typical small molecule, 6,13‐bis(triisopropylsilylethynyl) pentacene (TIPS), the crucial influence of conjugated polymers as additives on modulating the crystallization processes, crystalline structures, and carrier transport is unraveled. The conjugated polymer additives including poly[2,5‐bis(3‐alkylthio‐phen‐2‐yl)thieno(3,2‐b)thiophene (PBTTT) and poly(9,9‐di‐n‐octylfluorene‐alt‐benzothiadiazole) (F8BT) via a solution crystallization method can bring in crystalline structures that are not accessible by nonconjugated polymers, demonstrating superior order and enhanced carrier transport without external treatments. In such cases, polymorphism of the small molecules is manipulated by the features of conjugated polymers in the blend. According to optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X‐ray diffraction (XRD), different crystalline morphologies such as fibrous crystals from TIPS/PBTTT and rod‐like crystals from TIPS/F8BT are observed, which is determined by the crystalline habitats and solubility of conjugated polymers in small‐molecule/polymer blends. Meanwhile, organic field‐effect transistors (OFETs) based on TIPS/PBTTT and TIPS/F8BT blends are prepared for the purpose of exploring the electrical characteristics, yielding the mobility of 0.3 and 3.53 cm2 V−1 s−1, respectively. The conjugated‐polymer‐mediated polymorphism of small molecules can provide an attractive platform to explore the fundamental relationship between crystal stacking and electrical behaviors without altering the chemical structure. [ABSTRACT FROM AUTHOR]