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Mixed‐halide perovskites show promising applications in tandem solar cells owing to their adjustable bandgap. One major obstacle to their commercialization is halide phase segregation, which results in large open‐circuit voltage deficiency and J‐V hysteresis. However, the ambiguous interplay between structural origin and phase segregation often results in aimless and unspecific optimization strategies for the device's performance and stability. An atomic scale is directly figured out the abundant Ruddlesden‐Popper anti‐phase boundaries (RP‐APBs) within a CsPbIBr2 polycrystalline film and revealed that phase segregation predominantly occurs at RP‐APB‐enriched interfaces due to the defect‐mediated lattice strain. By compensating their structural lead halide, such RP‐APBs are eliminated, and the decreasing of strain can be observed, resulting in the suppression of halide phase segregation. The present work provides the deciphering to precisely regulate the perovskite atomic structure for achieving photo‐stable mixed halide wide‐bandgap perovskites of high‐efficiency tandem solar cell commercial applications. [ABSTRACT FROM AUTHOR]

A dynamically responsive hydrogel medium is prepared from two self‐assembling components, a polysaccharide (chitosan) and a surfactant (sodium dodecyl sulfate; SDS). It is shown that this medium can be patterned using an electrode "pen" to reconfigure supramolecular structure: cathodic writing induces neutral chitosan chains to form a crystalline network, while anodic writing generates cationic chitosan chains that electrostatically crosslink with anionic SDS micelles. Both supramolecular structures are re‐configurable and each is stabilized by structure‐induced shifts in chitosan's pKa, thus electronically written patterns can be erased, new patterns can be written, and patterns can be written in three dimensions. Further, it is shown that NaCl‐induced morphological transitions of the SDS micelles allow patterns to be reversibly concealed or revealed. To demonstrate the versatility of this medium for information storage, a quick response (QR) code is electronically written and it is shown that this code can be recognized by a standard cellphone app. This QR code can be concealed by making the medium opaque (i.e., by obscuring the pattern) or by making the pattern evanescent (i.e., by making pattern invisible). Overall, this work demonstrates that a dynamically responsive medium composed of simple, safe and sustainable components can be reversibly patterned with spatial and quantitative control using top‐down electronic inputs. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis, which converts carbon dioxide into hydrocarbon fuels, is a promising strategy to overcome both global warming and energy crisis. Herein, the geometric position of Cu and Ga on ultra‐thin CuGaS2/Ga2S3 is oriented via a sulfur defect engineering, and the unprecedented C2H4 yield selectivity is ≈93.87% and yield is ≈335.67 µmol g−1 h−1. A highly delocalized electron distribution intensity induced by S vacancy indicates that Cu and Ga adjacent to S vacancy form Cu–Ga metallic bond, which accelerates the photocatalytic reduction of CO2 to C2H4. The stability of the crucial intermediates (*CHOHCO) is attributed to the upshift of the d‐band center of ultra‐thin CGS/GS. The C–C coupling barrier is intrinsically reduced by the dominant exposed Cu atoms on the 2D ultra‐thin CuGaS2/Ga2S3 in the process of photocatalytic CO2 reduction, which captures *CO molecules effectively. This study proposes a new strategy to design photocatalyst through defect engineering to adjust the selectivity of photocatalytic CO2 reduction. [ABSTRACT FROM AUTHOR]

Complementary metal‐oxide‐semiconductor (CMOS) field‐effect transistors (FETs) are the key component of a chip. Bulk indium arsenide (InAs) owns nearly 30 times higher electron mobility µe than silicon but suffers from a much lower hole mobility µh (µe/µh = 80), thus unsuited to CMOS application with a single material. Through the accurate ab initio quantum‐transport simulations, the performance gap between the NMOS and PMOS is significantly narrowed is predicted and even vanished in the sub‐2‐nm‐diameter gate‐all‐around (GAA) InAs nanowires (NW) FETs because the inversion of the light and heavy hole bands occurs when the diameter is shorter than 3 nm. It is further proposed several feasible strategies for further improving the performance symmetry in the GAA InAs NWFETs. Short‐channel effects are effectively depressed in the symmetric n‐ and p‐type GAA InAs NWFETs till the gate length is scaled down to 2 nm according to the standards of the International Technology Roadmap for Semiconductors. Therefore, the ultrasmall GAA InAs NWFETs possess tremendous prospects in CMOS integrated circuits. [ABSTRACT FROM AUTHOR]

Constructing proper in vitro tumor immune microenvironment (TIME) is important for cancer immune‐therapy studies, while the selection of biomaterials is critical. As innate immune cells, macrophages can target and kill cancer cells in vivo at the early stage of tumor development. However, this targeting phenomenon has not been observed in vitro. Herein, a quasi‐3D in vitro cell culture model is constructed to mimic TIME by integrating hydrogel collagen as extracellular matrix for cells. In the collagen‐based quasi‐3D in vitro system, for the first time, it is found that macrophages can be attracted toward cancer cells along the dynamically reconstructed collagen fibers. By combining traction force microscopy and customized micro‐manipulator system, it is revealed that the collagen matrix‐transmitted tensile force signaling precisely guides the migration of macrophages toward cancer cells. The mechano‐responsiveness mechanism is related to the activation of mechanosensitive ion channels, and the induced local increase of calcium signal, which is proved to enhance the F‐actin assembly and to guide the cell migration. This novel mechanism advances the understanding of the role of collagen fibers in mechanotaxis of macrophages. Taken together, it has great potential for assisting biomaterial designs in developing new drug‐screening models and clinical strategies for cancer immune‐therapy. [ABSTRACT FROM AUTHOR]

The Zn2+ sluggish kinetics resulting from high desolvation barriers of Zn(H2O)62+ in the electrode/electrolyte interface restricts the practical application of Zn‐ion batteries (ZIBs). Herein, ethylene glycol (EG) molecules are inserted into V2O5·3H2O to form V‐EG nanoarray structures to improve the Zn2+ diffusion rate. Unlike most efforts focused on improving interlayer spacing and structural stability, the influence of EG on the Zn2+ desolvation and Zn2+ storage process are the main goals. Based on experimental and theoretical analysis, EG molecules are confirmed to participate in the reshaping of V2O5·3H2O morphology and Zn2+ solvation structure, which is beneficial to enhance the reaction kinetics and specific capacity. The polar group of the EG molecule leads it anchored in the VO skeleton and decreases the desolvation energy, while the steric hindrance of the low polarity group liberalizes Zn2+ transfer reversibly in the VO skeleton. Therefore, V‐EG delivers a higher ion diffusion coefficient and lower kinetic barrier. As expected, V‐EG exhibits a high specific capacity of 553 mA h g−1 at 0.3 A g−1 and a long cycle life of 10 000 cycles at 20 A g−1. This work provides a strategy to decrease the desolvation energy of Zn2+ in the interface of cathode materials toward advanced ZIBs. [ABSTRACT FROM AUTHOR]

Patients with diabetes mellitus (DM) suffer from a high risk of fractures and poor bone healing ability. Surprisingly, no effective therapy is available to treat diabetic bone defect in clinic. Here, a 3D printed enzyme‐functionalized scaffold with multiple bioactivities including osteogenesis, angiogenesis, and anti‐inflammation in diabetic conditions is proposed. The as‐prepared multifunctional scaffold is constituted with alginate, glucose oxidase (GOx), and catalase‐assisted biomineralized calcium phosphate nanosheets (CaP@CAT NSs). The GOx inside scaffolds can alleviate the hyperglycemia environment by catalyzing glucose and oxygen into gluconic acid and hydrogen peroxide (H2O2). Both the generated H2O2 as well as the overproduced H2O2 in DM can be scavenged by CaP@CAT NSs, while the initiated hypoxic microenvironment stimulates neovascularization. Moreover, the incorporation of CaP@CAT NSs not only enhance the mechanical property of the scaffolds, but also facilitate bone regeneration by the degraded Ca2+ and PO43− ions. The remarkable in vitro and in vivo outcomes demonstrate that enzymes functionalized scaffolds can be an effective strategy for enhancing bone tissue regeneration in diabetic conditions, underpinning the potential of multifunctional scaffolds for diabetic bone regeneration. [ABSTRACT FROM AUTHOR]

There are no significant differences between the control group and GOx contained groups, indicating the long-term biosafety of GOx contained scaffolds in vivo. 3D Printed Enzyme-Functionalized Scaffold Facilitates Diabetic Bone Regeneration The original image of lung in the Alg/GOx group was repeatedly clipped and used again in Figure S12 (Supporting information) for the Alg/GOx/CaP@CAT group in error. [Extracted from the article]

Synapse formation in complex neuronal network is a pivotal process for normal functioning of nervous system. Although intense research has been conducted, how neurons and axons are guided toward the target remains largely unclear. In traditional opinions, axons are directed through chemotaxis, while recently mechanotaxis has been brought up as a potential complementary mechanism, as it can provide delicately controlled signals in addition to the random diffusive chemical cues. To further explore the path‐finding mechanism, a quasi‐3D in vitro model for neuronal cells is constructed by integrating hydrogel collagen I as extracellular matrix (ECM), and primary mouse cortical neurons and PC12 cells are tested. It is strikingly found out that axons and neuronal cells can be precisely guided toward target neurites via ECM. By developing a label‐free traction force microscopy technique, the force networks among neurons are presented, validating that the fibrous matrix‐transmitted paratensile signals can assist the axon pathfinding. This precise axon guidance is related to the activation of mechanosensitive ion channels, calcium signaling, and probably the following F‐actin assembly. This mechanism can potentially assist developing clinical applications and designing biomaterials in near future. [ABSTRACT FROM AUTHOR]

Porous ultrathin 2D catalysts are attracting great attention in the field of electro/photocatalytic hydrogen evolution reaction (HER) and overall water splitting. Herein, a universal pH‐controlled wet‐chemical strategy is reported followed by thermal and phosphorization treatment to prepare large‐size, porous and ultrathin bimetallic phosphide (NiCoP) nanosheets, in which graphene oxide is adopted as a template to determine the size of products. The thickness of the resultant NiCoP nanosheets ranges from 3.5 to 12.8 nm via delicately adjusting pH from 7.8 to 8.5. The thickness‐dependent electrocatalytic performance is evidenced experimentally and explained by computational studies. The prepared large‐size ultrathin NiCoP nanosheets show excellent bifunctional electrocatalytic activity for overall water splitting, with low overpotentials of 34.3 mV for HER and 245.0 mV for oxygen evolution reaction, respectively, at 10 mA cm−2. Furthermore, the NiCoP nanosheets exhibit superior photocatalytic HER performance, achieving a high HER rate of 238.2 mmol h−1 g−1 in combination with commonly used photocatalyst CdS, which is far superior to that of Pt/CdS (81.7 mmol h−1 g−1). All these results demonstrate large‐size porous ultrathin NiCoP nanosheets as an efficient and multifunctional electro/photocatalyst for water splitting. [ABSTRACT FROM AUTHOR]

To enhance the energy density of batteries and explore intrinsic charge storage mechanism of the active materials, it is important to reduce or eliminate the use of non‐active materials in electrodes, such as binder and conductive additives. Herein, free‐standing Na4MnV(PO4)3@C (F‐NMVP@C) fiber membrane is fabricated and directly used as a sodium‐ion battery (SIB) cathode. In situ X‐ray diffraction reveals that the V3+/V4+ redox reaction occurs through a solid‐solution reaction while a two‐phase Mn2+/Mn3+ redox reaction is identified, and both are highly reversible. Meanwhile, ex situ electrochemical impedance spectroscopy reveals that both the ion diffusion coefficient and charge transfer resistance of F‐NMVP@C change reversibly during the Na+ intercalation/de‐intercalation. Battery full cells are assembled based on the free‐standing F‐NMVP@C cathodes and F‐Sb@C anodes, which manifests a high energy density (293 Wh kg−1) and good cyclability (87.5% after 100 cycles at 1 C). The high‐performance free‐standing cathodes and anodes shed light on the development of flexible SIBs. [ABSTRACT FROM AUTHOR]

The quinoid‐donor‐acceptor (Q‐D‐A) strategy has recently emerged as a promising approach for constructing high mobility semiconducting polymers. In order to fully explore the potential of this strategy in improving the charge transport and elucidating the structure‐property‐performance relationships in Q‐D‐A polymers, a series of new polymers with different electron acceptor units and backbone coplanarity have been synthesized and characterized. All of the resulting Q‐D‐A polymers exhibit much more planar backbone conformations in comparison to their donor‐acceptor (D‐A) counterparts. Moreover, organic field‐effect transistors based on Q‐D‐A polymers exhibit excellent effective hole mobilities in a range of 0.44 to 3.35 cm2 V−1 s−1, most of which are orders of magnitude higher than those of their corresponding D‐A polymers. Notably, the hole mobility of 3.35 cm2 V−1 s−1 is among the highest for the quinoidal‐aromatic polymers characterized by conventional spin‐coating methods. Furthermore, the role of electron acceptors in Q‐D‐A polymers has been comprehensively investigated. Polymers with stronger acceptor units are more inclined to deliver edge‐on lamellas, high film crystallinity, small effective hole masses, and decent operational stability. The detailed structure‐property‐device performance relationship will pave the way toward high performance semiconducting polymers using the potent Q‐D‐A strategy. [ABSTRACT FROM AUTHOR]

The crystal orientation of small molecules is one of the key parameters for developing high‐performance small molecule based organic field‐effect transistors. However, achieving a high degree of backbone alignment still remains a challenge, due to the sensitive nature of small molecules to processing conditions. Herein, the thin films of three conjugated small molecules, named as ZR1, ZR2‐C3, and Y6 are prepared by epitaxial‐crystallization on a highly oriented polyethylene (PE) substrate, resulting in the significant enhancement in charge transport properties. The maximum mobilities for aligned edge‐on molecules in the films enhance by up to 9.91 × 10−2 and 8.97 × 10−2 cm2 V−1s−1 for ZR1 and ZR2‐C3 films with conducting channel along small molecule backbones, which are 35‐ and 37‐fold that of the values evaluated in perpendicular to molecular backbones and nearly 23‐and 19‐fold beyond the values measured from unaligned films. Furthermore, the electron and hole mobilities of the small molecule Y6 with face‐on nature increase by nearly fourfold the values measured in perpendicular to the backbone direction and from unaligned films. This work demonstrates the epitaxial crystallization of thin films on oriented PE, offers a critical understanding of small molecules with different orientations and an effective approach for tuning charge transport toward high‐performance organic electronic applications. [ABSTRACT FROM AUTHOR]

While the use of molecular materials having long-lived triplet excited state(s) for harvesting solar energy could be an effective approach to boost up the power conversion efficiency (PCE) of organic solar cells (OSCs), the performances of this kind of OSCs as reported in the literature are low (< 2.9% PCE attained for the vacuum-deposited OSCs). Herein is described the realization of high performance OSCs by using gold(III) 5,10,15-triphenylcorrole ( Au-C1), gold(III) 10-( p-trifluoromethylphenyl)-5,15-diphenylcorrole ( Au-C2), and gold(III) 10-(pentafluorophenyl)-5,15-diphenyl-corrole ( Au-C3), as electron-donors. These gold(III) corroles display excited state lifetimes of ≥ 25 μs and low emission quantum yields of < 0.15%. With the complexes Au-C1, Au-C2, and Au-C3, vacuum-deposited OSCs, which give PCEs of 2.7%, 3.0%, and 1.8%, respectively, are fabricated. The PCE can be further boosted up to 4.0% after thermal treatment of the OSC devices. Meanwhile, a solution-processed OSC based on Au-C2 with a high PCE of 6.0% is fabricated. These PCE values are among the best reported for both types of vacuum-deposited and solution-processed OSCs fabricated with metal-organic complexes having long-lived excited states as electron-donor material. The underlying mechanism for the inferior performance of the reported OSCs is discussed. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is exploited as a promising strategy for cancer treatment. However, the hypoxic solid tumor and the lack of tumor‐specific photosensitizer administration hinder the further application of oxygen (O2)‐dependent PDT. In this study, a biodegradable and O2 self‐supplying nanoplatform for tumor microenvironment (TME)‐specific activatable cascade catalytic reactions‐augmented PDT is reported. The nanoplatform (named GMCD) is constructed by coloading catalase (CAT) and sinoporphyrin sodium (DVDMS) in the manganese (Mn)‐doped calcium phosphate mineralized glucose oxidase (GOx) nanoparticles. The GMCD can effectively accumulate in tumor sites to achieve an "off to on" fluorescence transduction and a TME‐activatable magnetic resonance imaging. After internalization into cancer cells, the endogenous hydrogen peroxide (H2O2) can be catalyzed to generate O2 by CAT, which not only promotes GOx catalytic reaction to consume more intratumoral glucose, but also alleviates tumor hypoxia and enhances the production of cytotoxic singlet oxygen from light‐triggered DVDMS. Moreover, the H2O2 generated by GOx‐catalysis can be converted into highly toxic hydroxyl radicals by Mn2+‐mediated Fenton‐like reaction, further amplifying the oxidative damage of cancer cells. As a result, GMCD displays superior therapeutic effects on 4T1‐tumor bearing mice by a long term cascade catalytic reactions augmented PDT. [ABSTRACT FROM AUTHOR]

The optimization of bulk heterojunction morphology is one of the most challenging topics in all‐small‐molecule organic solar cells. Herein, three small molecular donors based on dithieno[2,3‐d;2′,3′‐d′]benzo[1,2‐b;4,5‐b′]dithiophene (DTBDT) unit by systematically moving the branching point of the alkyl chain have been designed, synthesized, and applied in organic solar cells. Modifying the branching points enables the properties of the aggregation state to be tuned, and an efficient nanofiber‐based hierarchical morphology is successfully demonstrated by combining with different nonfullerene acceptors. The molecules with far branching points can form nanofibers in active layers, and theses nanofibers help the charge separation and charge transport in a large donor‐rich or acceptor‐rich domain of approximately 100 nm. Using nonfullerrene Y6 as an acceptor, the highest power conversion efficiency of 14.78% is obtained, which is one of the highest efficiencies in all‐small‐molecule organic solar cells. The strategy of modification of alkyl side chain branching points can be a practical way to actualize crystallinity control and active layer morphology for improving the performance of all‐small‐molecule organic solar cells. [ABSTRACT FROM AUTHOR]

Van der Waals p–n junctions of 2D materials present great potential for electronic devices due to the fascinating properties at the junction interface. In this work, an efficient gas sensor based on planar 2D van der Waals junctions is reported by stacking n‐type and p‐type atomically thin MoS2 films, which are synthesized by chemical vapor deposition (CVD) and soft‐chemistry route, respectively. The electrical conductivity of the van der Waals p–n junctions is found to be strongly affected by the exposure to NO2 at room temperature (RT). The MoS2 p–n junction sensor exhibits an outstanding sensitivity and selectivity to NO2 at RT, which are unavailable in sensors based on individual n‐type or p‐type MoS2. The sensitivity of 20 ppm NO2 is improved by 60 times compared to a p‐type MoS2 sensor, and an extremely low limit of detection of 8 ppb is obtained under ultraviolet irradiation. Complete and very fast sensor recovery is achieved within 30 s. These results are superior to most of the previous reports related to NO2 detection. This work establishes an entirely new sensing platform and proves the feasibility of using such materials for the high‐performance detection of gaseous molecules at RT. [ABSTRACT FROM AUTHOR]

Microneedle (MN), a miniaturized needle with a length‐scale of hundreds of micrometers, has received a great deal of attention because of its minimally invasive, pain‐free, and easy‐to‐use nature. However, a major challenge for controlled long‐term drug delivery or biosensing using MN is its low tissue adhesion. Although microscopic structures with high tissue adhesion are found from living creatures in nature (e.g., microhooks of parasites, barbed stingers of honeybees, quills of porcupines), creating MNs with such complex microscopic features is still challenging with traditional fabrication methods. Here, a MN with bioinspired backward‐facing curved barbs for enhanced tissue adhesion, manufactured by a digital light processing 3D printing technique, is presented. Backward‐facing barbs on a MN are created by desolvation‐induced deformation utilizing cross‐linking density gradient in a photocurable polymer. Barb thickness and bending curvature are controlled by printing parameters and material composition. It is demonstrated that tissue adhesion of a backward‐facing barbed MN is 18 times stronger than that of barbless MN. Also demonstrated is sustained drug release with barbed MNs in tissue. Improved tissue adhesion of the bioinspired MN allows for more stable and robust performance for drug delivery, biofluid collection, and biosensing. [ABSTRACT FROM AUTHOR]

This precise axon guidance mechanism is associated with the activation of mechanosensitive ion channels, calcium signals, and subsequent F-actin assembly. Axon pathfinding, extracellular matrix, mechanical signals, synapse formation Keywords: axon pathfinding; extracellular matrix; mechanical signals; synapse formation EN axon pathfinding extracellular matrix mechanical signals synapse formation 1 1 1 09/07/23 20230905 NES 230905 B Axon Pathfinding b In article number 2301926, Qihui Fan, Fangfu Ye, and co-workers show that the mechanical signals transmitted through the fibrous extracellular matrix enable precise guidance of axons and neuronal cells towards target neurites, leading to highly efficient neural network formation. [Extracted from the article]

High performance organic solar cells comprising gold(III) corroles as donors are demonstrated by C.‐M. Che and co‐workers. On page 4655, power conversion efficiencies of 4.0% and 6.0% are realized in optimized OSCs via vacuum and solution processes: among the best reported for both types of devices with triplet photoabsorbers. Their long excited‐state lifetimes (≥25 μs) and low luminescence quantum yields (<0.15%) may benefit OSC device performance. [ABSTRACT FROM AUTHOR]

In this work, for the first time, the addition of aluminum oxide nanostructures (Al2O3 NSs) grown by glancing angle deposition (GLAD) is investigated on an ultrathin Cu(In,Ga)Se2 device (400 nm) fabricated using a sequential process, i.e., post‐selenization of the metallic precursor layer. The most striking observation to emerge from this study is the alleviation of phase separation after adding the Al2O3 NSs with improved Se diffusion into the non‐uniformed metallic precursor due to the surface roughness resulting from the Al2O3 NSs. In addition, the raised Na concentration at the rear surface can be attributed to the increased diffusion of Na ion facilitated by Al2O3 NSs. The coverage and thickness of the Al2O3 NSs significantly affects the cell performance because of an increase in shunt resistance associated with the formation of Na2SeX and phase separation. The passivation effect attributed to the Al2O3 NSs is well studied using the bias‐EQE measurement and J–V characteristics under dark and illuminated conditions. With the optimization of the Al2O3 NSs, the remarkable enhancement in the cell performance occurs, exhibiting a power conversion efficiency increase from 2.83% to 5.33%, demonstrating a promising method for improving ultrathin Cu(In,Ga)Se2 devices, and providing significant opportunities for further applications. [ABSTRACT FROM AUTHOR]