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In this study, a breathable and strain‐insensitive multi‐layered electronic skin (e‐skin) capable of real‐time detection and distinction of electrocardiogram (ECG) signals, temperature, and skin hydration is developed. Leveraging a scalable benchtop method, sensing elements are transferred onto porous and hydrophobic substrates, followed by multi‐layer stacking to enable multimodal sensing. The sensing elements, a combination of carbon nanotube and nanoporous carbon (CNT@NPC) ink, are applied using strain‐insensitive patterned masks, then spray‐coated with styrene–ethylene–butylene–styrene (SEBS) to create a hierarchical porous network through phase separation. The CNT@NPC networks exhibit an improvement in strain insensitivity with active sensing capabilities due to their adaptable molecular tuning capacity and exceptional electrical conductivity. The porous SEBS substrate offers strong bonding with CNT@NPC attributed to the π–π interactions and high kinetic energy dispersion from spray coating allowing effective transfer. This unique design facilitates breathability, and miniaturization that minimizes the interference between different sensing modalities, ensuring accurate and reliable data acquisition. The breathability (3.49 mg cm−2 h−1) and the non‐smearing nature of the multi‐layered e‐skin enables simultaneous monitoring of temperature (0.198% °C−1), skin hydration (relative humidity = 0.77% %−1), and ECG (26 ± 1 dB) with continuous data transmission to a remote smartphone interface. [ABSTRACT FROM AUTHOR]

Piezoresistive pressure sensors, analyzing and converting external pressure signals to readable electrical signals for monitoring human health, are always subjected to simultaneously possess high signal‐linearity and signal sensitivity. Analogous to the control of sophisticated microstructure for increasing active sensing area, the control of gradient conductivity should enable a linear response via regulating the formed saturation current. Here, inspired by phase separation showing the feasibility of controlling material microstructure and conductivity, a high‐performance flexible pressure sensor via the simultaneous control of microgroove structure and wide‐range gradient conductivity is demonstrated. First, a laser‐etching and dopamine (DA)‐doping synergistic approach is used to induce selective phase separation in poly(3,4‐ethylenedioxythiophene): poly(styrenesulfonic acid) (PEDOT:PSS), achieving broad conductivity modulation (from 297 to 4525 S cm−1) and precise microgroove pattern (15.5 µm). Then, by designing conductivity‐gradient PEDOT: PSS‐based multi‐sublayers and microgroove interlocked structure, the sensor shows extraordinarily comprehensive performance of excellent stress‐sensing sensitivity (4 × 105 kPa−1), high linear responsiveness (99.85%) and wide‐range sensing ability (up to 100 kPa). Consequently, this sensor reveals excellent capability in detecting multi‐mode pressure changes and is expected to branch out into other electronic device designs as a general strategy for the precise manipulation of material physical‐chemical properties. [ABSTRACT FROM AUTHOR]

The morphology of the photoactive layer plays an important role in both the photoelectric effect and device performance of solution‐processed organic solar cells (OSCs). Optimizing the morphology requires precise control over the complex film formation kinetics, which are influenced by a range of factors from the solution state to the solid‐film state. This review delves into the in situ characterization technologies employed to understand the active layer formation process and explores strategies for controlling film formation during key stages, including solution aggregation, nucleation, crystal growth, and phase separation. Special attention is given to the mechanism by which these strategies enable real‐time morphology control during the printing process and their potential to facilitate direct printing of active layers with optimized morphology. The goal is to offer valuable insights and guidance for managing film formation kinetics in solution‐processed OSCs, ultimately addressing the challenges of real‐time morphology control in scale‐up printing and paving the way for high‐throughput production of post‐processing‐free devices. [ABSTRACT FROM AUTHOR]

The application of gel wearable sensors in aquatic environments is very promising, however, the preparation of underwater gel sensors with excellent anti‐swelling properties and sensing performance remains a great challenge. In this paper, a solvent exchange strategy is proposed to fabricate an anti‐swelling gel, in which the hydrophobic segments are induced to gather and microphase separation occurs inside the gel. The prepared gel possesses excellent anti‐swelling performance (swelling ratio of 4.79%), good mechanical properties (tensile strain of 712%), high sensitivity (GF = 1.07), and high linearity (R2 = 0.998, 0 to 70% strain range). Moreover, it can achieve high stability (more than 90 days) and fatigue resistance (1000 cycles at 50% strain) as an underwater sensor. Therefore, the designed underwater gel strain sensors can be utilized for monitoring human motion information, underwater distress and smart alarms, revealing the great potential application in the field of underwater strain sensors. [ABSTRACT FROM AUTHOR]

The central core in non‐fullerene acceptors (NFAs) plays a crucial role in determining the efficiency of organic photovoltaic (OPV) cells. To further advance the development of OPV cells, it is crucial to synthesize novel central cores for constructing high‐performance NFAs. Here, dibenzothiadiazolopyrrolothiophene (DBTPT) is introduced, a ladder‐type [1,2,5]thiadiazolo[3,4‐e]indole‐fused pentacyclic thiophene unit, into photovoltaic materials. By employing the DBTPT unit as the rigid molecular backbone and modifying the side chain of the thiophene π‐bridge, two new acceptor‐π‐acceptor'‐donor‐acceptor'‐π‐acceptor (A‐π‐A'DA'‐π‐A)‐type acceptors (T6 and T9) are synthesized. The effects of lateral alkyl and alkoxy side chains on the optoelectronic properties, charge transport, and molecular packing order are systematically investigated. When blended with polymer donor Poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)‐benzo[1,2‐b:4,5‐b']dithiophene))‐alt‐(5,5‐(1',3'‐di‐2‐thienyl‐5'7'‐bis(2‐ethylhexyl)benzo[1',2'‐c:4',5'‐c']dithiophene‐4,8‐dione))] (PBDB‐T), the blend film based on T9 with alkoxy side chains shows favorable molecular stacking and phase separation, resulting in excellent charge transfer performance. Benefiting low energetic disorder, PBDB‐T:T9‐based cell achieves an efficiency of 12.6% with a markedly low energy loss of 0.568 eV. The preliminary results demonstrate that the DBTPT unit has great potential for the construction of novel NFAs for high‐performance OPV cells. [ABSTRACT FROM AUTHOR]

Solvothermal synthesis is the predominant method for creating new structured covalent organic frameworks (COFs), yet it grapples with challenges in controlling shape and morphology. This issue is attributed to the unregulated solvent‐feeding process, which results in rapid polymerization and uncontrolled phase separation. Consequently, a two‐step solvent‐feeding process is reported for the solvothermal shaping of imine‐linked COF monoliths with hierarchical porosity. The synthesis conditions for COF powders reported in existing literature are directly utilized without extensive optimization; however, solvents are divided into two segments prior to feeding. A minor segment of solvents is employed to dissolve monomers, which polymerize in situ to form amorphous monoliths. Subsequently, the remaining organic solvent, along with an acetic acid aqueous solution, is added for crystallization. The versatility of this two‐step feeding process in producing COF monoliths is illustrated. The high‐quality COF monoliths demonstrate benzene uptakes ranging from 6.0 to 16.8 mmol g−1 at 298 K. This study confirms that the two‐step solvent feeding process can be effectively integrated with the conventional solvothermal method to enhance the solution‐processability of COFs. It is anticipated that this modified solvothermal approach can readily shape COFs to meet practical application requirements. [ABSTRACT FROM AUTHOR]

Enhancing the accessibility and utilization of active sites through mesopores in carbon anode materials is crucial for developing high‐power potassium‐ion hybrid supercapacitors (PIHCs). Here, a multiscale phase separation method combining block copolymer (BCP) microphase‐ and homopolymer (HP) macrophase‐separation is utilized to produce two model carbon materials with controlled mesopore orientation: open‐end (oe‐MCS) and closed‐end mesoporous carbon sphere (ce‐MCS). BCPs form identical cylindrical micelles, and HPs encapsulate these cylindrical micelles within spheres and control their orientations relative to the interface. This approach manipulates only the degree of mesopore openings in the MCS materials while maintaining all other factors at similar levels. Opening mesopores in carbon anode materials primarily enhances K+ adsorption capacity, reduces K+ diffusion length, and improves ion transport. Thus, oe‐MCS anode exhibits a higher specific capacity with a significant capacitive‐controlled contribution. The resulting PIHC device displays maximum energy and power densities of 103 Wh kg−1 and 12 300 W kg−1, respectively, along with capacity retention of 86.1% after 20 000 cycles at 2.0 A g−1. This study significantly advances the understanding of mesopore design to improve capacitive K+ storage in hard carbon materials, paving the way for the development of high‐power PIHCs. [ABSTRACT FROM AUTHOR]

Due to the mismatched aggregation behavior and limited compatibility between the donor and acceptor, it is a challenge for the active layer of organic solar cells (OSCs) to spontaneously realize well‐developed morphology in nonhalogenated solvents. In this contribution, an aggregation regulation strategy for acceptors with strong aggregation is developed via thiophene‐substituted alkyl chain engineering to fabricate high‐performance nonhalogenated solvent‐processed OSCs without an additive or post‐treatment. With the replacement of alkyl chains with steric conjugated thiophene‐substituted alkyl chains, the resulting acceptor (namely BTP‐2T, BTP‐T, and BTP‐T‐BO) shows reduced aggregation to match the polymer donor D18‐Cl using toluene as a processing solvent, enabling ordered molecular arrangement and uniform phase separation morphology. Especially, the combined modification of the asymmetric thiophene‐substituted inner chain and branched outer side chains for BTP‐T‐BO enables the formation of a superior nanoscale bi‐continuous interpenetrating network along with ordered and compact molecular packing in the D18‐Cl:BTP‐T‐BO blend. As a result, an excellent PCE of 18.05% is achieved in the D18‐Cl:BTP‐T‐BO‐based device using toluene as the processing solvent without any extra treatment, which is the highest value for nonhalogenated solvent‐processed OSCs without any extra treatment. [ABSTRACT FROM AUTHOR]

The molecular conformation of giant molecule acceptors (GMAs) plays a significant role in regulating the intermolecular interactions and their photovoltaic performances in organic solar cells (OSCs). For the linear GMA GT‐l, the stronger homo‐molecular interaction causes its aggregation being weakly affected by the donor, thus forming an ordered molecular stacking and proper phase separation in its blend film. The star‐shaped GMA GT‐s‐based blend film shows a dominant hetero‐molecular interaction that suppresses the aggregation of the donor and acceptor, resulting in smaller phase separation and more uniform vertical phase distribution. While for another star‐shaped GMA GTs, the weakest hetero‐molecular interaction causes its blend film to form larger phase separation. Therefore, the GT‐l based OSC with PM6 as donor shows the highest charge mobilities, the fastest charge transfer (CT) process, reduced energy loss and less charge recombination, contributing to a higher power conversion efficiency (PCE) of 19.03%. Comparatively, the PCEs of the OSCs based on GTs and GT‐s are 18.05% and 17.58% respectively. Notably, all the three GMAs based OSCs show excellent thermal stability and long‐term storage stability. This study provides a facile strategy by tuning the linking unit and its connecting mode for designing highly efficient and stable organic photovoltaic materials. [ABSTRACT FROM AUTHOR]

Despite impressive progress in the field, there are still several major bottlenecks in producing fibers from recombinantly produced spider‐silk‐like proteins to replicate the extraordinary mechanical properties of spider major ampullate silk. The conventional artificial fiber spinning processes rely primarily on organic solvents to coagulate proteins into fibers and require complex post‐treatments to obtain fibers with valuable properties. This is due to challenges in obtaining soluble silk proteins, but also because the native silk spinning process leading to the hierarchical organization of the silk proteins is not fully understood and is hard to replicate in a manner applicable to industrial settings. Here, recombinant spider‐silk fusion proteins are efficiently produced and processed into as‐spun fibers with a toughness modulus of 120 MJ m−3 and extensibility of 255% using solely aqueous solutions. The spider‐silk fusion proteins assemble in a manner similar to that reported for native spider silk: they phase separate induced by salting out, followed by alignment and a secondary structure transition triggered by shear forces and dehydration. Finally, the design of the fusion silk proteins enables straightforward functionalization of the fibers under mild all‐aqueous conditions via a simple biomolecular click reaction both pre‐ and post‐spinning. [ABSTRACT FROM AUTHOR]

With the drive toward the development of large‐area organic solar cells (OSCs), there is a critical need for advanced fabrication techniques that ensure both their efficiency and scalability. In particular, a shift from toxic halogenated solvents to safer non‐halogenated alternatives such as o‐xylene, which have lower environmental and health impacts, is required. However, transitioning to non‐halogenated solvents can lead to serious problems, including aggregation within the active layer, which compromises film morphology and the resulting efficiency of OSCs. To address this aggregation, in the present study, the 2‐ethylhexyl (EH) groups in L8‐BO(EH‐EH) are replaced with longer chains (2‐heptylundecyl [HU], 2‐decyltetradecyl [DT], and 2‐dodecylhexadecyl [DH] groups) to synthesize the non‐fullerene acceptors (NFAs) of L8‐BO(HU‐HU), L8‐BO(HU‐DT), and L8‐BO(HU‐DH). The NFAs with the longer alkyl chains are highly soluble in o‐xylene and produce highly uniform films, making them more suitable for use in large‐area OSCs. Using the NFAs, slot‐die‐coated organic solar modules with an active area of 200 cm2 are fabricated; the L8‐BO(HU‐DT)‐based module exhibits an impressive power conversion efficiency of 11.44%. This work thus underscores the asymmetrical elongation of alkyl chains in the NFAs to mitigate severe NFA phase separation and improve film printability in the practical production of organic solar modules. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots (PQDs) show high potential for new‐generation light‐emitting diodes (LEDs) due to their outstanding optoelectronic properties. Even though the red PQD‐LEDs can be realized through mixing halide in the PQDs to tune their spectroscopies, the PQDs may suffer from phase separation under a high electric field, predominantly affecting LED applications. Herein, a ligand‐pinning‐assisted approach is reported to tune the spectroscopies of CsPbI3 PQDs, in which vinyl phosphonic acid (VPA) is applied as function ligands to regulate the nucleation and growth of PQDs during the synthesis. Systematically experimental studies and theoretical calculations are conducted to comprehensively understand the functions of the VPA ligands during the PQD synthesis, which reveals that the VPA ligands with high binding energy with Pb2+ cations could firmly anchor on the surface matrix of PQDs without desorption, regulating the growth of PQDs and thus resulting in tunable spectroscopies being realized. Meanwhile, VPA could also renovate the defective surface matrix of PQDs, substantially diminishing trap‐induced nonradiative recombination. Consequently, red PQD‐LEDs deliver a high external quantum efficiency of 22.83%, which is significantly improved compared with the control devices. This work provides a new avenue to tune the spectroscopies of PQDs toward high‐performing LEDs. [ABSTRACT FROM AUTHOR]

Poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS) aerogel has attracted much attention in bioelectronics, electromagnetic shielding, and energy‐related systems due to its biocompatibility, intrinsic electronic conductivity, and favorable processability. However, fabrication of highly conductive and low‐density PEDOT:PSS aerogels is still challenging. In this work, highly conductive PEDOT:PSS aerogels are produced via ice‐templated pre‐assembly followed by a specially designed thawing process in H2SO4 solution. Upon optimization of heat and mass transfer during the thawing process, along with the unique ice template effect, the microstructure and thin walls of PEDOT:PSS frozen samples are well preserved. Importantly, the porous structure and thin walls facilitate diffusion of H2SO4 into polymer matrix, inducing phase separation of PEDOT:PSS, thus increasing PEDOT crystallinity and partially removing of PSS component. As a result, the as‐prepared pristine PEDOT:PSS aerogels exhibit a high electrical conductivity of 1200 ± 231 S m−1 along the freezing direction at a low density of 15.3 ± 1.5 mg cm−3, enhanced mechanical properties, and a competitive electromagnetic interference shielding efficiency of 25 115 dB cm2 g−1. Moreover, the compressed aerogels show good performances as active materials in symmetrical supercapacitors with thickness‐independent capacitance (maximum 2.1 F cm−2 at 1.0 mA cm−2) and in current collector‐free micro‐supercapacitors processed by laser carving. [ABSTRACT FROM AUTHOR]

Barrier membrane, a key material for guided bone regeneration surgery, is applied between soft and hard tissue interfaces in complex oral environment. The abilities to integrate contradictory requirements and self‐regulate the local microenvironment are highly desirable for barrier membrane but remain challenging to achieve. Herein, inspired by the leaf's hierarchical multifunctional synergy, a kind of superstructured porous membrane (SPM), integrating asymmetric surface pores, interconnected macropores and functional micropores, is developed based on the combination of breath figure and phase separation. For the SPM, the densely porous layer can inhibit penetration of soft tissue cells and maintain osteogenic space, and the loosely porous layer with interconnected microporous channels can effectively promote the adhesion and proliferation of osteoblasts, help to transport nutrients, and expose functional components. Meanwhile, porous carbon nanospheres introduced into SPM as multifunctional core components can ameliorate the undesirable microenvironment by scavenging reactive oxygen species, repairing bioelectrical environment, and killing bacteria, thus achieving multiple bioactive pro‐healing functions for efficient bone regeneration in vivo. These findings can open an appealing avenue for developing high‐performance barrier membranes as well as many other implant materials. [ABSTRACT FROM AUTHOR]

Hydrogels hold great promise in the field of flexible electronics. Attempts in this area tend to the microstructure design of hydrogels, giving them specific adhesion and multi‐sensing functions. Here, a novel phase separation‐derived anisotropic adhesive structural color hydrogel film is presented for visually flexible electronics. The hydrogel film is generated by template replicating colloidal crystal by using phase separation emulsions of hydrophilic monomer (acrylic acid, AA), hydrophobic monomer (lauryl methacrylate, LMA), co‐monomer ([2‐(methacryloyloxy) ethyl] dimethyl‐(3‐sulfopropyl) ammonium hydroxide (SBMA)), surfactants (hexadecyl trimethyl ammonium bromide, CTAB) and initiator (ammonium persulphate (APS)). The appearance of phase separation results in asymmetric morphologies of hydrogel film, imparting them with anisotropic adhesive performance. Attributed to the formation of inverse opal scaffold structure, the hydrogel film is featured with vivid structural color, showing superior capability in self‐reporting mechanical behavior. Additionally, benefitting from the presence of abundant ions, the hydrogel film exhibits great conductivity. Thus, the resultant hydrogel film is demonstrated with stable dual‐signal sensing properties involving color‐changing and conductivity feedback ability to respond to human activities. These features make the proposed anisotropic adhesive structural color hydrogel film highly potential in the flexible electronic field. [ABSTRACT FROM AUTHOR]

Man‐made superhydrophobic membranes are of interest for various applications in energy, environment, and medical fields. However, simultaneously achieving durable superhydrophobicity, robust waterproofness, and high breathability of the membranes is still challenging. Herein, an efficient and powerful strategy is reported to create superhydrophobic membranes with perdurable liquid repellency and robust breathability via combining humidity‐induced electrospinning with coat‐crosslinking technology. The micro/nano rough structure is in situ constructed based on manipulating the phase separation of electrospun jets; meanwhile, the waterborne acrylic resins are bridged to the surface of nanofiber to endow the membranes with stable low surface energy via coating and crosslinking treatment. Eventually, the resultant membranes present superhydrophobicity with a water contact angle of ≈154°, good self‐cleaning and anti‐icing properties, robust waterproofness of 83.4 kPa, and high breathability of 3.71 kg m−2 d−1. More interestingly, the nanomaterials can maintain durable superhydrophobicity even after exposure to various severe conditions. The successful creation of high‐performance superhydrophobic membranes opens a new avenue for synthesizing advanced functional materials for application in a variety of fields. [ABSTRACT FROM AUTHOR]

Mechanical stretchability is a vital criterion for the wearable application of organic solar cells (OSCs), while the excessive rigidity of fused‐ring small molecular acceptors make the photovoltaic film hard to meet the stretchable requirements. Herein, an effective strategy is developed to construct an intrinsically stretchable active layer by inserting copolymer PM6‐b‐PYSe as an interlayer between layer‐by‐layer processed D18 and BTP‐eC9. The copolymer interlayer shunts the penetration of BTP‐eC9 and facilitates an appropriate phase separation, favoring the enhanced crack onset strain of 17.69% compared to the D18/BTP‐eC9 film (9.67%). Combining with the optimal energy levels, prolonged carrier lifetime, and suppressed bimolecular recombination aroused by the incorporation of PM6‐b‐PYSe, the D18/PM6‐b‐PYSe/BTP‐eC9‐based OSC yields an encouraging efficiency of 17.97%. In particular, the device demonstrates excellent mechanical property, which can retain over 80% after 4000 bending cycles. This work provides an effective strategy to simultaneously enhance the intrinsic mechanical stretchability and photovoltaic performance of flexible OSCs. [ABSTRACT FROM AUTHOR]

Flexible bioelectronics have a large range of applications in the field of human health monitoring and human‐machine interfaces. Among various bioelectronics, flexible electrodes have been widely studied. However, it is still lack of investigation in the development of electrodes with high signal quality and long service life. Here, a sponge inspired flexible electrode based on cellulose aerogel is developed via thermally induced phase separation. Due to its flexibility, the electrode can easily conform to skin and achieve a higher signal‐to‐noise ratio (SNR) than the commercial rigid electrode. At the same time, the aerogel electrode with a sponge‐like structure can absorb solutions several times their own weight (≈800%). In addition, the dope of polypyrrole coated silver nanowires (AgNWs@PPy) improves its intrinsic bactericidal activity (antibacterial rate above 97.8%) and the cellulose‐based material itself offers good skin compatibility. Therefore, all these features contribute to a longer service life, while has been proven in electrophysiological signals recording. The SNR of electrocardiogram (ECG) signals recorded by aerogel electrode in 24 h is ≈15% higher than that of commercial electrode. Apart from that, when the commercial electrode is unavailable for eye‐open (EO) and eye‐closed (EC) paradigm in 12 h, the aerogel electrode can still record clear electroencephalogram (EEG) features. [ABSTRACT FROM AUTHOR]

With the increasing demand for information security, current anti‐counterfeiting methods not only suffer from issues such as low information density and vulnerability to forgery, but also inherently involve a trade‐off between information capacity and readout methods. This paper reports a high‐security solution using hierarchical pattern with perfect combination of micro self‐wrinkle and nano phase‐separation as physical unclonable function (PUF) labels, which is generated through self‐organization of anthracene‐functionalized poly(styrene‐block‐butadiene‐block‐styrene) (SBS‐CAN) under UV exposure. The double‐layer morphologies formed by the wrinkle and phase separation are adjustable, independent, and stable. The obtained hierarchical PUF labels exhibit random and unique features similar to the minutiae of fingerprints at both micro and nano scales, ensuring a well‐balanced bit uniformity (>0.492), high uniqueness (>0.496), and outstanding reliability (>96%). As a consequence of the multi‐layered combination of morphologies, the designed PUF label possesses an information density about 1010 times higher than that of human fingerprints. The PUF labels can be quickly obtained through simple visual scanning and exhibit sufficient security. To cope with various application environments, the advanced authentication pipeline designed LPLA guarantees robust label recognition capability in real‐world scenarios. A practical integrated anti‐counterfeiting authentication system is developed by combining hierarchical PUF labels and authentication pipeline. [ABSTRACT FROM AUTHOR]

The emerging mechanically active wound dressing has been perceived as one of the most effective strategies to accelerate wound closure in a non‐invasive manner. However, the development of wound dressing with body temperature‐stimulated shrinkage behavior and superior mechanical capability is still a severe challenge. Here, a thermal‐shrinkable, stretchable, and tough fibrous tape is developed via the construction of “stiff‐elastic” binary component, as well as manipulation of the fiber stretching and phase separation. The resultant polyurethane (PU)/polyvinyl butyral (PVB) fibrous membrane (FM) shows a rapid and considerable shrinkage of 70.0% after exposure at 37 °C for 12 h. The shrunk PU/PVB FMs exhibit excellent mechanical performance including high elongation of 364.4%, large toughness of 26.6 MJ m−3 and rapid thermal‐recoverable capability with 80.4% and 71.8% restoration of stress and dissipated energy respectively. The in vivo study in rat full‐thickness skin model with 2 cm‐diameter circular wounds demonstrates that the thermal‐shrinkable PU/PVB FMs can enhance wound contraction and healing. Furthermore, the ex vivo rabbit organ model indicates the possibility of thermal‐shrinkable PU/PVB FMs in defect contraction of diverse tissues. This work may offer a promising way in the development of body temperature‐triggered mechanically active fibrous dressings for defects repair. [ABSTRACT FROM AUTHOR]

Polymer gels, consisting of cross‐linked polymer network systems swollen by a solvent, show great potential in biomedicine, flexible electronics, and artificial muscles, due to their tissue‐like mechanical properties. Due to the presence of a large amount of solvent, the improvement of the mechanical properties of the polymer gel is a challenge. Moreover, combining high toughness with useful properties, such as 3D printability or shape‐memory, in one polymer gel system is even more challenging. In this study, a simple and efficient method is developed for the fabrication of tough polymer gels by polymerizing 2‐hydroxyethyl methacrylate (HEMA) in a mixture of poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG). The polymerized elastic networkpresents distinct compatibility with PEG (compatible) and PPG (poorly compatible), resulting in in‐situ phase separation at the microscale. The resulting phase‐separated gel demonstrates high strength (8.0 MPa), favorable fracture strain (430%), and large toughness (17.0 MJ m−3). The separated hard phasewith a high glass transition temperature (75 °C) endows the whole soft polymer gel with the property of shape memory at room temperature. Finally, the fabrication of tunable tough PEGgels is combined with 3D printing as well as with shape memory properties, demonstrating the use of PEGgels for 4D printing. [ABSTRACT FROM AUTHOR]

Information coding, recording, encryption, and decryption are of great importance in the field of anti‐counterfeiting, especially in the current AI information era. Herein, a paper‐like hydrogel composed of solely H‐bonded poly(vinyl alcohol) (PVA) and poly(n‐vinylcaprolactam) (PNVCL), namely VAPN, is developed for multiple ways of encryption and decryption based on chemical‐induced phase separation. It not only exhibits excellent ability of ink absorption and retention by the noncovalent H‐bonds and n−π* interactions and good mechanical strength but also maintains a negligible volume change during the phase separation that is crucial for the information fidelity. Given that the noncovalent interactions are the driving force to trigger the phase separation in the hydrogel, available chemical inks are numerous ranging from small molecules to polymers. Furthermore, together with thermally induced phase separation, the different dynamic processes of the association and dissociation between ink molecules and the hydrogel endow the latter with reversible information recording and self‐erasing, temporary or permanent, and customized encryption and decryption. [ABSTRACT FROM AUTHOR]

Although tissue culture plastic has been widely employed for cell culture, the rigidity of plastic is not physiologic. Softer hydrogels used to culture cells have not been widely adopted in part because coupling chemistries are required to covalently capture extracellular matrix (ECM) proteins and support cell adhesion. To create an in vitro system with tunable stiffnesses that readily adsorbs ECM proteins for cell culture, a novel hydrophobic hydrogel system is presented via chemically converting hydroxyl residues on the dextran backbone to methacrylate groups, thereby transforming non-protein adhesive, hydrophilic dextran to highly protein adsorbent substrates. Increasing methacrylate functionality increases the hydrophobicity in the resulting hydrogels and enhances ECM protein adsorption without additional chemical reactions. These hydrophobic hydrogels permit facile and tunable modulation of substrate stiffness independent of hydrophobicity or ECM coatings. Using this approach, it is shown that substrate stiffness and ECM adsorption work together to affect cell morphology and proliferation, but the strengths of these effects vary in different cell types. Furthermore, it is revealed that stiffness-mediated differentiation of dermal fibroblasts into myofibroblasts is modulated by the substrate ECM. The material system demonstrates remarkable simplicity and flexibility to tune ECM coatings and substrate stiffness and study their effects on cell function. [ABSTRACT FROM AUTHOR]

Constructing Mott-Schottky heterojunctions in nanohybrids is an effective strategy for facilitating electron transfer and optimizing the electronic structure of active sites; however, challenges remain. Herein, a selenium-induced phase separation strategy is proposed and successfully construct NiSe2/MoSe2 Mott-Schottky heterojunctions on N-doped brain coral carbon nanospheres (N-BCCSs). Owing to built-in electric fields, optimized electronic density, and unique nanoflake/sphere structures, the designed NiSe2/MoSe2@N-BCCSs carbon-based Mott-Schottky catalysts achieved satisfactory electrocatalytic performance. When serving as a counter electrode for the triiodide reduction reaction (IRR), a power conversion efficiency of 8.49% is obtained, which outperformed that of conventional Pt electrodes (7.80%). When the NiSe2/MoSe2@N-BCCSs are used as electrocatalysts for the hydrogen evolution reaction (HER), their overpotential (η[sub 10]) is as low as 119 mV, which is significantly better than that of other transition-metal selenides. This research demonstrates a new concept for constructing Mott-Schottky heterojunctions and provides a new direction for investigating multifunctional carbon-based composites. [ABSTRACT FROM AUTHOR]

Conductive hydrogels possessing high conductivity, stretchability, and biocompatibility are promising materials for underwater devices and bioelectronics. However, typical hydrogels often exhibit low electrical conductivity, which is insufficient for applications requiring high electronic communication. A common approach to increase hydrogel conductivity is to introduce conductive fillers; however, this usually implies a partial sacrifice of stretchability, biocompatibility, and water content. In addition, the electrical properties of hydrogels tend to be unstable due to rehydration in aqueous environments. In this study, a conductive hydrogel composite is fabricated from silver nanowires (AgNWs) and poly(vinyl alcohol) (PVA) employing a synergistic method of freezing and salting‐out treatments. This combined method constructs a hierarchical hydrogel structure and increases the local concentration of AgNWs by inducing continuous phase separation. The resultant conductive hydrogel composites exhibit ultra‐high electrical conductivity (≈1739 S cm−1) and electrical stability in aqueous environments while maintaining high water content (≈87%), stretchability (≈480%), and excellent biocompatibility. To illustrate the capabilities of the conductive hydrogel composites, they are applied to bionic sharks, underwater soft circuitry, and electrocardiogram electrodes. [ABSTRACT FROM AUTHOR]

In practical applications, LiCoO2 (LCO) cathode is usually charged with a constant current plus constant voltage (CC+CV) procedure to obtain higher capacity delivery. However, the harsh condition upon CC+CV procedure causes the accelerated capacity decay of LCO. Herein, the fading mechanism of LCO cycling upon CC+CV procedure at 4.6 V versus Li/Li+ is first revealed. Comparing with a pure CC charging, the accelerated capacity decay of LCO upon CC+CV procedure is attributed to both the bulk and surface structure damages: i) the CV charging triggers more H1‐3 phase separation, leading to the generation of lattice dislocations, curved Co‐O layers, and ultimately the bulk microcracks inside the LCO particles; ii) upon cycle, the CV charging causes more side reactions and more surface structure collapse issues, including forming thick surface phase transition layer (PTL), causing more Co dissolution, forming thick and loose CEI layer, etc., which seriously increases the charge transfer resistance and reduces the interface Li+ transport kinetics. This work provides a new insight into the fading mechanism, and shows a new pathway for designing more advanced LCO cathodes. [ABSTRACT FROM AUTHOR]

Volatile solid (VS)‐additives are regarded as an effective tool to manipulate morphology of sequential deposited (SD) active layers for improving power conversion efficiencies (PCEs) of organic solar cells (OSCs), while the independent effect of VS‐additives on donor and acceptor layers is often overlooked. Herein, a new VS‐additive named 2‐(2‐methoxyphenyl)benzo[b]thiophene (BTO) is synthesized and applied in SD binary PM6/L8‐BO active layers. Introducing it into bottom PM6 layer (PM6+), BTO has a low volatility and longer volatilization distance, which prolongs the interaction time between BTO and L8‐BO in PM6+/L8‐BO film, leading to an over‐aggregated L8‐BO. While inserting it into top L8‐BO layer (L8‐BO+), the fast evaporation of BTO and excellent dipole interaction between BTO and L8‐BO help to enhance molecular absorption, crystallinity, and ordered packing of PM6/L8‐BO+ system. Therefore, an optimized morphology with proper phase separation is achieved to increase exciton dissociation and charge transfer properties, restrain charge recombination and energy loss of OSCs, yielding an impressive PCE of over 19%. Furtherly, using D18 instead of PM6, binary SD‐systems offer a record‐high PCE of 19.16%. The developed selective optimization strategy for SD active layers provides a deep insight into the working mechanism of VS‐additives for boosting PCE of OSCs. [ABSTRACT FROM AUTHOR]

Controlled sequential crystallization of donors and acceptors is a critical factor for achieving enhanced phase separation and efficient charge transfer performance in polymer solar cells (PSCs). In this study, a comprehensive investigation of a structurally simple solvent additive, 1‐fluoro‐2‐iodobenzene (OFIB) is conducted, which efficiently controls the morphology of the active layer, resulting in fibrous assembly and significantly enhancing the power conversion efficiency from 16.34% to 18.38% based on the PM6:L8‐BO system. Density functional theory, molecular dynamics simulations, and grazing incidence small‐ and wide‐angle X‐ray scattering techniques reveal that the addition of OFIB to the processed blend aligns the orientation of the acceptor molecules, thereby enhancing the overall π–π stacking in the active layer. OFIB establishes nearly equal‐strength π–π interactions with the conjugated frameworks of both the donor and acceptor materials, benefiting from the multiple electron conjugation between its iodine atom and the conjugated framework in the active layer. Femtosecond‐timescale photophysical studies demonstrate that the OFIB‐optimized active layer shows reduced exciton losses at the donor–acceptor interface. This study offers a new perspective on the mechanism underlying the function of solvent additives and presents a comprehensive research methodology that will guide the development of next‐generation non‐fullerene acceptors for efficient PSCs. [ABSTRACT FROM AUTHOR]

Halogenation of non‐fused ring electron acceptors (NFREAs) plays an important role in regulating their optoelectronic properties. However, the underlying mechanisms and their impact on the performance of organic solar cells (OSCs) have remained unclear. Herein, a series of halogenated NFREAs incorporating F, Cl, and Br, are prepared to study their effect on crystallization kinetics, phase separation, molecular packing, and charge transport. Among various halogenation strategies, chlorination minimizes the Coulomb attractive energy between donor and acceptor, thereby facilitating exciton dissociation. In situ UV–vis absorption tests reveal that chlorinated acceptors exhibit a longer crystallization time, effectively suppressing excessive molecular aggregation and enhancing overall crystallinity. Additionally, chlorinated acceptors exhibit a longer exciton diffusion length, which promotes exciton dissociation while mitigating charge recombination in the devices. Consequently, two chlorinated NFREAs, TCN‐Cl, and PCN‐Cl, yield an impressive power conversion efficiency (PCE) of 14.85% and 15.30%, respectively, when blended with PM6 and J52 donors. These values represent the highest reported PCEs to date for NFREAs with A‐π‐A'‐π‐A and A‐π‐D‐π‐A structures. The study elucidates the crucial role of chlorination in extending exciton diffusion length and crystallization time. These effects significantly benefit phase separation within the active layers, enhance charge separation, and suppress recombination for achieving high‐efficiency OSCs. [ABSTRACT FROM AUTHOR]

Traditional artificial skin gels often only focuses on a single perspective and overlooks the necessity of multidimensional synergistic design for sensitivity enhancement. To address these problems, the innovative introduction of dual solvents on the surface of polyacrylamide/sodium alginate gel induces to the transformation of supramolecular interactions including ion coordination, crystalline alcohol, and phase separation, synergistically achieving adjustable wrinkle wavelengths (304.2 ± 19.9 to 2393.5 ± 95.9 µm) and modulated chemical compositions with tunable moduli (87.5 ± 3.3 to 157.6 ± 3.7 kPa). This flexible strategy allows the construction of long‐range ordered wrinkled microstructures of three‐dimensional surfaces and complex morphologies. Meanwhile, the bridge effect induced by crystalline alcohols directs the insertion of ethanol molecules into the polymer chains, effectively reducing intramolecular friction. Benefiting from the small wavelength and low modulus dominated by crystalline alcohol, the wrinkled gel exhibits extremely high sensitivity of 164 kPa−1 (<0.5 kPa) and wide detection range (44.3 kPa). The wrinkled gel remains stable high sensitive to detect micro‐ and large stress, tactile perception, and human motion behaviors. This work proposes a new strategy for constructing highly sensitive bioinspired skin from multiple dimensions, showing broad application prospects in the fields of bioengineering and behavioral cognition. [ABSTRACT FROM AUTHOR]

Highly active and durable air electrodes are crucial for the commercialization of reversible proton ceramic electrochemical cells (R‐PCECs) for large‐scale energy conversion and storage that may be developed by introducing oxygen ion, electron, and proton triple conducting species into the electrode materials. Here, a new triple conducting nanocomposite is reported as a promising air electrode of R‐PCECs, which consists of a dominated cubic perovskite Ba0.5Sr0.5Co0.72Fe0.18Er0.09O3‐δ and a minor Er2O3 phase, developed by Er doping induced phase separation of Ba0.5Sr0.5(Co0.8Fe0.2)0.9Er0.1O3‐δ precursor. The Er doping stimulates the primary perovskite phase to possess excellent hydration capability and oxygen activation ability, while the Er2O3 minor phase, as a high‐speed proton transport channel, further cooperates with the perovskite main phase to boost the kinetic rate of the electrode for both oxygen reduction and evolution reactions (ORR/OER). As a result, the corresponding R‐PCEC achieves extraordinary electrochemical performance in fuel cell (1.327 W cm−2 at 650 °C) and electrolysis modes (−2.227 A cm−2 at 1.3 V and 650 °C), which exceed the similar cell with a typical Ba0.5Sr0.5Co0.8Fe0.2O3‐δ single‐phase perovskite air electrode by 82.3% and 122.7%, respectively. This Er‐doping induced phase separation provides a new way for new bifunctional electrodes development. [ABSTRACT FROM AUTHOR]

Porous carbon materials have increasingly drawn interest for applications ranging from supercapacitive energy storage to bioengineering. However, a simple and scalable fabrication process of such materials, employing low‐cost chemical compounds without sacrificing morphological and chemical control, remains lacking. Here, a novel, rapid, continuous bottom‐up strategy for synthesizing structurally tunable porous carbon network films on insulating and conductive substrates is reported. By employing rapid thermal annealing (RTA) of a commercial polyacrylonitrile‐based blend, simultaneous phase separation and thermal crosslinking are induced, effectively freezing the structure. Subsequent burning of degradable components generates a porous carbon framework (d¯pore${\bar{d}}_{{\mathrm{pore}}}$ ≈ 360 to 700 nm) doped with nitrogen and oxygen atoms. Introducing a boron‐containing reagent in the precursor solution enables boron doping and pore size reduction as small as 20 nm, enhancing materials' performance. The direct fabrication of micro‐supercapacitors on stainless steel substrates is demonstrated, achieving an areal capacitance of 12.7 mF cm−2 at 50 mV s−1, with ≈98% retention after 10 000 charge/discharge cycles. The benefit of boron doping is further highlighted for wound healing applications. Because RTA is already an established industrial method, this platform directly facilitates the synthesis of functional porous heteroatom‐doped carbon structures using commercial polymers and dopants for various applications. [ABSTRACT FROM AUTHOR]

As a new class of soft materials, continuous emulsion channels have been successfully stabilized solely by rough colloids, which exhibit unique capability in sterically controlling liquid–liquid interfaces. Once jammed at the interface, the roughness‐enhanced frictions can slow down the dynamics of phase separation, and the interlocking behaviors would constrain their relative motions and generate force structures that provide mechanical support for the created emulsions. Ethanol is used to ensure the particles' absorption, whose migration can modify the interfacial tension, and increase the solubility of active ingredients (e.g., curcumin). Applying rough colloids in ethanol‐containing systems opens new pathways toward the generation of novel structures and materials, where the parallel but separate functionalities provided by various phases demonstrate wide‐ranging applications, especially in delivery systems with variably soluble components. [ABSTRACT FROM AUTHOR]

Vitrimers are polymer networks with dynamic covalent bonds that allow the network to reconfigure its connectivity while maintaining a constant number of chemical bonds at all temperatures. The melt viscosity of vitrimers thus gradually decreases with temperature. This behavior makes vitrimers more difficult to process than typical thermoplastics using conventional processing techniques, such as extrusion. Although many strategies have been reported to address this issue, it remains challenging to overcome a key tradeoff between improving the processability or the mechanical performance. Herein, this work presents a new strategy for overcoming this tradeoff in the context of elastomeric vitrimers. The approach entails the cross‐linking of a functionalized low‐glass transition (Tg) polymer matrix with an incompatible high‐Tg polymer featuring pendant groups with complementary reactivity. When compared to a conventional homogeneous vitrimer, the microphase‐separated materials prepared by reactive extrusion present improved tensile properties and creep resistance at room temperature while also exhibiting enhanced processability at high temperature. These enhanced properties are a consequence of the combination of the phase separation between the soft and hard phases, the restriction of dynamic cross‐linking reactions within the interfacial zones, and the judicious selection of the Tg of the hard phase to be in between the use and processing temperatures. [ABSTRACT FROM AUTHOR]

Current state‐of‐the‐art Li batteries use single‐phase electrolytes; however, these electrolytes often encounter difficulty in simultaneously fulfilling the nonidentical electrochemical requirements of cathodes and anodes. Here, a class of immiscible binary liquid electrolyte (BLE) is designed by starving free solvent molecules. Based on their electrochemical stability window, 1,2‐dimethoxyethane (DME) and succinonitrile (SN) are selected as model solvents for Li‐metal anodes and LiNi0.8Co0.1Mn0.1 (NCM811) cathodes, respectively. Li bis(fluorosulfonyl)imide (LiFSI), which promotes Li+ solvation (i.e., reduces free solvents), enables the phase separation of the miscible solvent mixture (SN−DME), and an increase in its concentration strengthens the coordination of Li+−FSI− in the solvation sheath, thus yielding (anion‐derived) fluorine‐rich electrode–electrolyte interphases. The resulting BLE allows 4.4 V Li‐metal full cells to exhibit a stable capacity retention under a constrained cell condition (Li (20 µm, 4.1 mAh cm−2)||NCM811 (3.8 mAh cm−2), N (negative)/P (positive) capacity ratio = 1.08), which exceed those of previously reported binary liquid electrolytes. [ABSTRACT FROM AUTHOR]

Energy‐free thermal regulation is in great demand nowadays. Thermochromic materials are widely explored and used in smart windows. However, most thermochromic materials have fixed transition temperature and still suffer from poor stability. To overcome this challenge, a thermochromic polymer coating based on ion–dipole interaction with switchable transition temperature, high stability toward several harsh environments, self‐healing, and radiative cooling property is developed. It can continuously tune from transparent to opaque according to the temperature change. The lower critical transition temperature can be tuned from 33 to 43 °C by simply adjusting the composition of ionic liquids. Owing to the fluorine polymer backbone and dynamic ion–dipole interactions, it can also keep stable in aquatic, −20 °C, and 70 °C environments and self‐heal upon damage thus prolonging its working life for real applications. [ABSTRACT FROM AUTHOR]

Inkjet printing (IJP) is a roll‐to‐roll (R2R) compatible fabrication method for large‐area organic solar cells (OSCs). Unlike the coating process, the films are formed through droplet leveling and merging during IJP, and the pre‐deposited droplets are partly dissolved by the subsequent droplets. Such a process yields undesired printing pattern lines, especially in large‐area printed films. This study reveals that such a temperature‐dependent "drying lines‐related" phase separation morphology has caused component variation in the organic blend films, which leads to an obvious inhomogeneity of photocurrent in the printed OSCs. Such a phenomenon is attributed to the solubility difference between organic donor and acceptor molecules in the main printing solvent. A composite solvent strategy of ortho‐dichlorobenzene (oDCB)/trimethylbenzene (TMB) and tetralin (THN) is developed to solve this problem. The introduction of THN suppresses the formation of printing drying lines during high‐temperature printing due to the preferential miscibility of acceptor in THN, leading to the efficiency improvement to 13.96% and 15.78% for the binary and ternary devices. In addition, the 1 cm2 device with a disruptive pattern gives an efficiency of 12.80% and a certificated efficiency of 12.18%. [ABSTRACT FROM AUTHOR]

Spatially directed biomineralization of nanocrystals for specific optical purposes in biological systems and elucidation of the mechanism of biomineralized nanocrystals remains a fascinating but extremely challenging task. Herein, the biomineralization of tunable gold nanocrystals with in situ protein coronas by intracellular liquid‐liquid phase separation (LLPS) for in situ molecule surface‐enhanced Raman spectrum (SERS) analysis and tumor fluorescence identification. The anisotropic nanocrystals are realized by regulating LLPS, in which the nucleation of nanocrystals is at the protein secondary structural site (β‐Corner) of the droplet, the different adsorption energies of crystal surfaces further promote the directional growth of nanocrystals. Interestingly, gold nanocrystals with ultra‐narrow fluorescence emission at half‐peak width and ultra‐long Stokes shift and can obtain in situ molecular fingerprint information of protein corona to achieve by SERS. Of note are the anisotropic nanocrystals to differentiate clinical patient tumor tissue samples. Therefore, this study reveals the mechanism of intracellular tunable nanocrystal biomineralization and provides the basis for its biomedical application. [ABSTRACT FROM AUTHOR]

All‐small‐molecule organic solar cells (ASM‐OSCs), which consist of small‐molecule donors and acceptors, have recently been studied extensively to eliminate the batch‐to‐batch variation from polymer‐based donor or acceptor. On the other hand, the control of their active layer morphology is more challenging due to the similar chemical structure and miscibility of small‐molecule donor and small‐molecule accepter. Hence, this study develops a dual‐additive‐driven morphology optimization method for ASM‐OSCs based on BTR‐Cl:Y6. One solid additive – 1,4‐diiodobenzene (DIB) and one liquid additive – diiodomethane (DIM) are selected, making use of their distinct interaction mechanisms with Y6 and BTR‐Cl. It is found that DIB can form a eutectic phase with Y6, which can increase the intermolecular interactions and modulate the acceptor phase separation, while the simultaneous volatilization of DIM suppresses the over‐aggregation of BTR‐Cl during the film casting process. As a result of the synergistic morphology tuning, the optimized device delivers a power conversion efficiency (PCE) as high as 15.2%, among the highest PCE reported to date for binary ASM‐OSCs without solvent annealing treatment. This work demonstrates the potential of morphology tuning via the incorporation of dual additives into ASM‐OSCs, enabling them to achieve comparable efficiencies to those of conventional polymer/small‐molecule based OSCs. [ABSTRACT FROM AUTHOR]

Organic photodetectors (OPDs) with spectral response extending from ultraviolet to near‐infrared domains are of great interest for many applications. Morphological impact on the performance of photomultiplication (PM)‐type OPDs, however, is still rarely investigated so far. Herein, a non‐fullerene acceptor, Y6‐Se‐HD, is synthesized, in which heavier selenium atoms substitute the sulfur atoms in the core of Y6, and used for fabricating PM‐OPDs. The resulting devices exhibit remarkable PM effects in a very broadband spectral range covering from 320 to 1090 nm. A maximum EQE value of ≈6500% at 860 nm is achieved at a low bias of −1.0 V. As compared with the device prepared with Y6 molecules, the Y6‐Se‐HD OPDs exhibited much enhanced performance. From the morphological analysis, we infer that Y6‐Se‐HD almost covers the entire active layer and avoids the direct contact of the hole‐trapping donor polymers with the Ag electrode, thereby resulting in stronger charge trapping and preventing possible charge recombination and/or quenching. Furthermore, finer phase separation between the donor and acceptor molecules also facilitates hole trapping and strengthens the PM effects. This research highlights the importance of morphological effects on the PM‐OPDs and demonstrates one approach for controlling the device morphology. [ABSTRACT FROM AUTHOR]

The commercialization of organic solar cells (OSCs) requires the use of roll‐to‐roll coating technology. However, it is generally believed that all‐small‐molecule (ASM) systems cannot form high‐quality films in most film‐fabrication technologies except for spin coating, mainly due to their strong crystallinity and low solution viscosity. Herein, it is found that the small molecule donor and acceptor system with strong intermolecular interaction can weaken the molecular self‐aggregation during film formation. As a result, all‐small‐molecule organic solar cells (ASM‐OSCs) are successfully fabricated using the green solvent tetrahydrofuran via spin coating as well as slot‐die coating technology. Under the optimal conditions, the devices achieve power conversion efficiency (PCE) of 14.05% and 13.41% prepared by spin coating and slot‐die coating, respectively. Moreover, a large‐area device with an area of 1 cm2 achieve a PCE of 10.65% by slot‐die coating. The study of the device performance and the active layer morphology reveal a unique film optimization mechanism in ASM‐OSCs. In the slot‐die coating process, a high‐quality film is formed due to the significantly suppressed crystallinity of the small molecule donor; with further thermal annealing, the crystallization‐induced phase separation enables an optimized morphology. This study proves that high‐performance ASM‐OSCs can be fabricated by the industrial‐compatible method. [ABSTRACT FROM AUTHOR]

The correlations between semiconductor type and gas sensing properties in soluble acene/polymer blends have not yet been examined. Here, the phase separation mechanism in pseudo‐liquid phase blend film is investigated and an unusual solid‐state morphology that is effective for amperometric gas sensing performance is demonstrated. In 6,13‐bis(triisopropylsilylethynyl) pentacene (TIPS–pentacene)/poly(fluorine‐co‐triarylamine) (PTAA) blend, two phases are uniformly mixed, without being completely phase‐separated due to the similar solubility and surface tension. On the other hand, in 2,8‐difluoro‐5,11‐bis(triethylsilylethynyl) anthradithiophene (diF–TES ADT)/PTAA blend, the diF−TES ADT molecules are segregated both at the air–film, and film–substrate interfaces, and subsequently crystallized with a high degree of crystal perfection. In the meanwhile, Marangoni‐flow induces crater‐like via hole structure of PTAA at the middle layer. In situ measurement of (ultraviolet–visible) UV–vis absorption spectra and computational calculation reveal kinetics of liquid–solid–crystal transition in relation to the functional groups of soluble acene. Interestingly, flow driven hole structure of PTAA in diF–TES ADT/PTAA blend film allows the target NO2 gas to selectively penetrate the channel region, thereby enhancing sensitivity toward NO2, while decreasing affinity with other gases. The results provide protocols for fabricating highlperformance field‐effect transistors and gas sensors in a blending system. [ABSTRACT FROM AUTHOR]

The first synthesis of hierarchical porous metal–organic frameworks (HP‐MOFs) is reported through a solvent evaporation‐induced co‐assembly of polystyrene‐block‐poly(ethylene oxide) (PS‐b‐PEO) and MOF building blocks. The growth of MOFs is restricted to confined spaces formed by self‐assembled PS‐b‐PEO, and mesopores and/or macropores are created after removing PS‐b‐PEO by solvent rinsing. This approach avoids phase separation and competitive interactions between templates and MOF building blocks. Both amorphous and crystalline HP‐MOFs can be synthesized by finely controlling MOF growth conditions. Additionally, HP‐MOFs (ZIF‐L sheets) with honeycomb‐like channels show significantly enhanced incorporation of large guest molecules compared to microporous MOFs. This study establishes an efficient synthetic strategy for preparing HP‐MOFs with highly accessible mesopores and macropores for applications involving large molecules. [ABSTRACT FROM AUTHOR]

All‐small‐molecule organic solar cells (ASM‐OSCs) are challenging for their inadequate efficiency and device stability due to their more susceptive morphology. Herein, a family of isomeric small molecule donors (SMDs) is synthesized based on the benzodithiophene–terthiophene core with linear, 1st carbon, and 2nd carbon position branched butyl‐based rhodanine for ASM‐OSCs, respectively. The single crystal of thiophene‐substituted model T‐s‐Bu forms a more compact intermolecular packing with herringbone structure than slip‐layered packing‐based T‐n‐Bu and T‐i‐Bu. SM‐i‐Bu and SM‐s‐Bu show slightly blue‐shifted absorption and deepened HOMO levels in the neat film compared to SM‐n‐Bu. SM‐s‐Bu:BO‐4Cl blend films have distinct face‐on packing orientations and suitable fibrous phase separation along with more apparent microcrystals. Finally, SM‐s‐Bu:BO‐4Cl‐based device yields an improved power conversion efficiency of 16.06% compared to 15.12% and 8.22% for SM‐n‐Bu:BO‐4Cl and SM‐i‐Bu:BO‐4Cl, which is one of the top‐ranked results for BTR‐series SMDs in binary ASM‐OSCs. More importantly, the excellent storage stability with a T80 lifetime of over 1700 h and decent thermal stability is realized in SM‐s‐Bu:BO‐4Cl. This work highlights that the isomeric terminal alkyl with a branching point directly connected to the backbone for SMDs is a promising strategy for improving the crystal packing and film morphology and achieving highly efficient and stable ASM‐OSCs. [ABSTRACT FROM AUTHOR]

Wide‐bandgap perovskite is a vital part of perovskite‐based tandem solar cells. Currently, wide‐bandgap perovskites are typically based on mixed‐halide (I/Br) materials, but suffer from photoinduced phase separation. The pure‐iodide formamidine/cesium (FA/Cs) based FAxCs1−xPbI3 perovskites with high Cs content are good candidates, whereas the control of crystallization is challenging due to the complex crystallization kinetics. Here, pure‐iodide FA0.5Cs0.5PbI3 wide‐bandgap perovskite solar cells is reported. As an acidic diammonium salt, methylenediaminium dichloride (MDACl2) is applied as an additive to control the whole crystallization process of perovskite films, including both nucleation and crystal growth. Starting from the solution chemistry, the MDACl2 additive with acidity and strong solvation properties can effectively regulate the chemical composition of perovskite precursor, thus inhibiting the growth of undesired 1D intermediates during the nucleation process. Besides, the incorporation of larger‐sized MDA2+ into the lattice compensates for the tolerance factor and accelerates the ion exchange reaction between FA+ and Cs+ in the crystal growth process. As a result, the crystallinity of the perovskite films is significantly improved, benefitting from the dual function of MDACl2. Finally, the efficiency of hole transport layer‐free carbon electrode‐based wide‐bandgap perovskite solar cells reaches 18.52%, which is the highest reported so far. [ABSTRACT FROM AUTHOR]

All small molecule organic solar cells (ASM‐OSCs) have numerous advantages but lower power conversion efficiencies (PCEs) than their polymer equivalents, which is largely due to the suboptimal nanoscale network structure in a bulk heterojunction (BHJ). Herein, new small molecule donors with symmetric/asymmetric hybrid cyclopentyl‐hexyl side chains are designed, accounting for manipulated intermolecular interactions and BHJ morphology. Theoretical and experimental results reveal that the asymmetric cyclopentyl‐hexyl side chains modification has a significant influence on potential energy surface and intermolecular interaction that can ensure preferable molecular assembly and regulate the D/A interfacial energetics, thus boosting the exciton dissociation and charge transport when pairing with a wide‐used acceptor L8‐BO. Concurrently, a nanoscale bicontinuous interpenetrating network with optimal domain size can be fully evolved in the BHJ layer. As a consequence, the As‐TCp‐based binary device achieves a superior PCE of 16.46% in comparison to that of the controlled symmetric counterparts S‐BF (14.92%) and A‐TCp (15.77%), and ranks one of best performance among ASM‐OSCs. This study demonstrates that precise manipulation of the cyclo‐alkyl chain in combination with the asymmetric 2D side chain strategy is an effective synergistic approach to control intermolecular interaction and nanoscale bicontinuous phase separation for achieving high‐performance ASM‐OSCs. [ABSTRACT FROM AUTHOR]

Developing new polymerized small molecular acceptor (PSMA) is pivotal for improving the performance of all‐polymer solar cells. On the basis of this newly developed CH‐series small molecule acceptors, two PSMAs are reported herein (namely PZC16 and PZC17, respectively). To reduce the molecular torsion caused by the traditional aromatic π‐bridges, non‐aromatic conjugated units (ethynyl for PZC16 and vinylene for PZC17) are adopted as the linkers and their effect on the photo‐physical properties as well as the device performance are systematically investigated. Both polymer acceptors exhibit co‐planar molecular conformation, along with broad absorption ranges and suitable energy levels. In comparison with the PM6:PZC16 film, the PM6:PZC17 film exhibits more uniform phase separation in morphology with a distinct bi‐continuous network and better crystallinity. The PM6:PZC17‐binary‐based devices exhibit a satisfactory PCE of 16.33%, significantly higher than 9.22% of the PZC16‐based devices. Impressively, PM6:PZC17‐based large area device (ca. 1 cm2) achieves an excellent PCE of 15.14%, which is among the top performance for reported all‐polymer solar cells (all‐PSCs). [ABSTRACT FROM AUTHOR]

Molecular innovation is highly desirable to achieve efficient all‐small‐molecule organic solar cells (SM‐OSCs). Herein, three small‐molecule donors (SMDs) with alkylated thiazole side groups (namely BO‐1, HD‐1, and OD‐1), which differ only in the alkyl side chain are reported. Although these SMDs possess similar absorption profiles and molecular energy levels, their crystallinity and miscibility with BTP‐eC9 slightly decrease along with the elongation of the alkyl side chain. After blending with BTP‐eC9, different miscibility leads to different degrees of phase separation. Among these SM‐OSCs, the HD‐1‐based device shows a decent bulk‐heterojunction (BHJ) morphology with proper phase separation and more dynamic carrier behavior. Thus, compared to the BO‐1 and OD‐1‐based devices, the HD‐1‐based device achieves a higher short‐circuit current of 26.04 mA cm−2 and a fill factor of 78.46%, leading to an outstanding PCE of 17.19%, which is one of the highest values among SM‐OSCs. This work provides a rational design strategy of SMDs for highly efficient SM‐OSCs. [ABSTRACT FROM AUTHOR]

The investigation of drying dynamics and kinetic quenching depth related degradation of high‐performance photoactive materials with scalable coating techniques demands significant research attention. Herein, film formation kinetics regulated crystallinity, preferential orientation and vertical phase separation of the active layers is revealed, which then further affects exciton diffusion, dissociation, charge‐transport and recombination processes. By suppressing over aggregation/crystallization in slow drying process and overcoming quenching of disordered liquid phase in fast‐dried films, the optimized PM6:BTP‐eC9‐based organic solar cells obtain power conversion efficiencies up to 16.81%. In addition, photoluminescence lifetime distribution is found to be an alternative probe for kinetic quenching depth that governs the degradation rate. This study provides valuable insights into the control of thin film formation kinetics during scalable processing and develops an effective way to associate the kinetic quenching depth with morphological degradation for mechanistic understanding of long‐term stability. [ABSTRACT FROM AUTHOR]

Solar steam generation (SSG) through hydrogel‐based evaporators has shown great promise for freshwater production. However, developing hydrogel‐based evaporators with stable SSG performance in high‐salinity brines remains challenging. Herein, phase‐separated polyzwitterionic hydrogel‐based evaporators are presented with sponge‐like structures comprising interconnected pores for stable SSG performance, which are fabricated by photopolymerization of sulfobetaine methacrylate (SBMA) in water‐dimethyl sulfoxide (DMSO) mixed solvents. It is shown that driven by competitive adsorption, the structures of the resulting poly(sulfobetaine methacrylate) (PSBMA) hydrogels can be readily tuned by the volume ratio of DMSO to achieve phase separation. The optimized phase‐separated PSBMA hydrogels, combining the unique anti‐polyelectrolyte effects of polyzwitterionic hydrogels, demonstrate a rapid water transport capability in brines. After introducing photothermal polypyrrole particles on the surface of the phase‐separated PSBMA hydrogel evaporators, a stable water evaporation rate of ≈2.024 kg m−2 h−1 and high solar‐to‐vapor efficiency of ≈97.5% in a 3.5 wt.% brine are obtained under simulated solar light irradiation (1.0 kW m−2). Surprisingly, the evaporation rates remain stable even under high‐intensity solar irradiation (2.0 kW m−2). It is anticipated that the polyzwitterionic hydrogel evaporators with sponge‐like porous structures will contribute to developing SSG technology for high‐salinity seawater applications. [ABSTRACT FROM AUTHOR]