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Reticular chemistry has been a cornerstone in the design of novel 2D materials. Despite numerous possibilities for topological arrangements, only a few with high symmetry can form stable networks. Here, starting from 2D carbons, four types of highly stable tessellations are discovered, which consist of chains of non‐hexagonal rings separated by hexagonal ribbons. A modified Read–Shockley model is established to perfectly describe the stability of these highly stable frameworks, which is based on the interaction between non‐hexagonal rings. Moreover, these four types of tessellations and the modified Read–Shockley model are found to be of general validity in designing highly stable 2D materials, which is verified by the calculations on polymorphs of boron nitride and molybdenum disulfide. Besides, among the studied 2D carbon allotropes, two semi‐metallic structures with highly anisotropic Dirac cones and one semimetal with a Dirac nodal line at the Fermi level are discovered, as protected by their D2h symmetry. Spin‐orbital coupling is further found to open small bandgaps for these three Dirac structures, making them nontrivial topological insulators. The in‐depth understanding of the stability of 2D crystals in this study provides a new way for rational design of 2D crystals that may show peculiar electronic structures. [ABSTRACT FROM AUTHOR]

Heterocycle‐linked phthalocyanine‐based COFs with close‐packed π–π conjugated structures are a kind of material with intrinsic electrical conductivity, and they are considered to be candidates for photoelectrical devices. Previous studies have revealed their applications for energy storage, gas sensors, and field‐effect transistors. However, their potential application in photodetector is still not fully studied. The main difficulty is preparing high‐quality films. In our study, we found that our newly designed benzimidazole‐linked Cu (II)‐phthalocyanine‐based COFs (BICuPc‐COFs) film can hardly formed with a regular aerobic oxidation method. Therefore, we developed a transfer dehydrogenation method with N‐benzylideneaniline (BA) as a mild reagent. With this in hand, we successfully prepared a family of high crystalline BICuPc‐COFs powders and films. Furthermore, both of these new BICuPc‐COFs films showed high electrical conductivity (0.022–0.218 S/m), higher than most of the reported COFs materials. Due to the broad absorption and high conductivity of BICuPc‐COFs, synaptic devices with small source‐drain voltage (VDS=1 V) were fabricated with response light from visible to near‐infrared. Based on these findings, we expect this study will provide a new perspective for the application of conducting heterocycle‐linked COFs in synaptic devices. [ABSTRACT FROM AUTHOR]

The lack of ambipolar polymers with balanced hole (μh) and electron mobilities (μe) >10 cm2 V−1 s−1 is the main bottleneck for developing organic integrated circuits. Herein, we show the design and synthesis of a π‐extended selenium‐containing acceptor‐dimeric unit, namely benzo[c][1,2,5]selenadiazol‐4‐yl)ethane (BBSeE), to address this dilemma. In comparison to its sulfur‐counterpart, BBSeE demonstrates enlarged co‐planarity, selective noncovalent interactions, polarized Se−N bond, and higher electron affinity. The successful stannylation of BBSeE offers a great opportunity to access acceptor‐acceptor copolymer pN‐BBSeE, which shows a narrower band gap, lower‐lying lowest unoccupied molecular orbital level (−4.05 eV), and a higher degree of backbone planarity. Consequently, the pN‐BBSeE‐based organic transistors display an ideally balanced ambipolar transporting property with μh and μe of 10.65 and 10.72 cm2 V−1 s−1, respectively. To the best of our knowledge, the simultaneous μh/μe values >10.0 cm2 V−1 s−1 are the best performances ever reported for ambipolar polymers. In addition, pN‐BBSeE shows an excellent shelf‐storage stability, retaining over 85 % of the initial mobility values after two months storage. Our study demonstrates the π‐extended acceptor‐dimeric BBSeE is a promising acceptor building block for constructing high‐performance ambipolar polymers applied in next‐generation organic integrated circuit. [ABSTRACT FROM AUTHOR]

The lack of ambipolar polymers with balanced hole (μh) and electron mobilities (μe) >10 cm2 V−1 s−1 is the main bottleneck for developing organic integrated circuits. Herein, we show the design and synthesis of a π‐extended selenium‐containing acceptor‐dimeric unit, namely benzo[c][1,2,5]selenadiazol‐4‐yl)ethane (BBSeE), to address this dilemma. In comparison to its sulfur‐counterpart, BBSeE demonstrates enlarged co‐planarity, selective noncovalent interactions, polarized Se−N bond, and higher electron affinity. The successful stannylation of BBSeE offers a great opportunity to access acceptor‐acceptor copolymer pN‐BBSeE, which shows a narrower band gap, lower‐lying lowest unoccupied molecular orbital level (−4.05 eV), and a higher degree of backbone planarity. Consequently, the pN‐BBSeE‐based organic transistors display an ideally balanced ambipolar transporting property with μh and μe of 10.65 and 10.72 cm2 V−1 s−1, respectively. To the best of our knowledge, the simultaneous μh/μe values >10.0 cm2 V−1 s−1 are the best performances ever reported for ambipolar polymers. In addition, pN‐BBSeE shows an excellent shelf‐storage stability, retaining over 85 % of the initial mobility values after two months storage. Our study demonstrates the π‐extended acceptor‐dimeric BBSeE is a promising acceptor building block for constructing high‐performance ambipolar polymers applied in next‐generation organic integrated circuit. [ABSTRACT FROM AUTHOR]

Intrinsically stretchable light‐emitting polymer semiconductors are essential building blocks for bioelectronics and display textiles. Stretchability is challenging for rigid conjugated polymers unless sacrificing charge mobility by introducing amorphous domains. High‐performance light‐emitting properties designed with twisted angle are undesirable for conductive materials. Hence, the concurrent strategies hardly satisfy the balance of stretchability, light‐emitting and mobility. Herein, a morphology engineering is proposed by controlling micro‐crystalline and limiting aggregation, that four intrinsically stretchable emissive polymers with good charge mobility based on indacenodithiophene (IDT) are obtained. Polymers reveal good emission properties with high photoluminescence quantum yields (PLQY) of about 20%, while stretchable modulus and charge mobility are tunable by backbone and weight. Specifically emphasizing, IDT‐2T‐H retains high performance of charge mobility and PLQY even at 100% strain. Therefore, organic light emitting diodes are fabricated based on it and showing the luminance of 176.2 cd cm−2, which verifies the potential of technique to reconcile integration of stretchability, light‐emitting, and mobility. This is the first attempt to integrate balanced mechanical, optical, and electrical properties through micro‐crystalline aggregation‐limited morphology in one polymer, offering a feasible approach to advanced integrated circuit and multi‐functional electronics in the future. [ABSTRACT FROM AUTHOR]

Constructing uniform covalent organic framework (COF) film on substrates for electronic devices is highly desirable. Here, a simple and mild strategy is developed to prepare them by polymerization on a solid‐liquid interface. The universality of the method is confirmed by the successful preparation of five COF films with different microstructures. These films have large lateral size, controllable thickness, and high crystalline quality. And COF patterns can also be directly achieved on substrates via hydrophilic and hydrophobic interface engineering, which is in favor of preparing device array. For application studies, the PyTTA‐TPA (PyTTA: 4,4′,4′′,4′′′‐(1,3,6,8‐Tetrakis(4‐aminophenyl)pyrene and TPA: terephthalaldehyde) COF film has a high photoresponsivity of 59.79 μA W−1 at 420 nm for photoelectrochemical (PEC) detection. When employed as an active material for optoelectronic synaptic devices for the first attempt, it shows excellent light‐stimulated synaptic plasticity properties such as short‐term plasticity (STP), long‐term plasticity (LTP), and the conversion of STP to LTP, which can be used to simulate biological synaptic functions. [ABSTRACT FROM AUTHOR]

Recently, conductive metal–organic frameworks (c‐MOFs) have drawn tremendous attention for the application in oxygen evolution reaction (OER) due to their superior conductivity and highly accessible active sites. Herein, a facile method is reported to prepare a series of bimetallic c‐MOFs (NixFe1‐x‐THQ, THQ = tetrahydroxy‐1,4‐benzoquinone hydrate) by using the smallest benzene‐based ligand with high‐density catalytic active sites for OER. By adjusting the ratio of Ni/Fe, a series of catalysts with optimal electronic structures and adsorption capacity to intermediates, and faster charge transport are obtained. Among them, Ni0.5Fe0.5‐THQ exhibits superior catalytic performances for OER with a low overpotential of 272 mV at 10 mA cm−2, a small Tafel slope of 47.9 mV, and robust operation for 40 h with no detectable activity decay, which is far superior to commercial RuO2, most of traditional MOFs and even some monometallic conductive MOFs. Moreover, both the measured and simulated results manifest that Ni0.5Fe0.5‐THQ can tailor the d‐band center, and induce the directional transfer of electrons, optimizing the rate‐determining step and adsorption capacity to intermediates during OER, thus exhibits superior electrochemical activity. This work not only presents a strategy to fabricate an electrocatalyst with remarkable OER performance but also promotes the development of THQ‐based c‐MOFs for electrocatalysis. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are a type of crystalline porous polymer composed of light elements through strong covalent bonds. COFs have attracted considerable attention due to their unique designable structures and excellent material properties. Currently, COFs have shown outstanding potential in various fields, including gas storage, pollutant removal, catalysis, adsorption, optoelectronics, and their research in the sensing field is also increasingly flourishing. In this review, we focus on COF‐based sensors. Firstly, we elucidate the fundamental principles of COF‐based sensors. Then, we present the primary application areas of COF‐based sensors and their recent advancements, encompassing gas, ions, organic compounds, and biomolecules sensing. Finally, we discuss the future trends and challenges faced by COF‐based sensors, outlining their promising prospects in the field of sensing. [ABSTRACT FROM AUTHOR]

A N, S co‐doped carbon with abundant vacancy defects (NSC) anchored Pt single atoms (SAs) and nanoclusters (NCs) derived from coal pitch by a self‐assembly‐pyrolysis strategy is reported and a defect‐induced electron redistribution effect based on Pt SAs‐Pt NCs/NSC catalyst is proposed for electrocatalytic hydrogen evolution reaction (HER). The optimized catalyst featuring Pt‐N3S1 SAs and Pt NCs dual active sites exhibit excellent HER activity with an overpotential of 192 mV at a current density of 400 mA cm−2, a turnover frequency of 30.1 s−1 at an overpotential of 150 mV, which the mass activity is 13716 mA mgPt−1, 7.4 times higher than that of 20% Pt/C catalyst. In situ Raman revealsa direct correlation between the defect structure of the catalyst and hydrogen adsorption during the reaction process. Density functional theory calculation shows the defect‐induced electron redistribution between Pt‐N3S1 SAs and Pt NCs. The electrons are transferred from Pt NCs to Pt SAs, which increases the number of electrons on the surface of Pt SAs and enhances the adsorption ability of H+. Meanwhile, the dissociation ability of H* on the Pt NCs is promoted, thus synergistically promoting the HER process. [ABSTRACT FROM AUTHOR]

Y‐series non‐fullerene acceptors (NFAs) have achieved great progress in organic solar cells (OSCs). Most research attention is currently paid to their molecular engineering to improve the efficiency of OSCs. However, as n‐type organic semiconductors, the relationship between their molecular packing structures and charge transport properties is mostly ignored. Herein, it is clarified how the molecular packing of Y‐series NFAs fundamentally determines their charge transport properties by manipulating their crystal stacking via sidechain engineering. Therefore, branched alkyl/alkoxy substitutions are taken on a reference NFA (Y6‐1O), affording three derivatives, namely 1OBO‐1, 1OBO‐2, and 1OBO‐3. Results show that while the replacement of branched alkyl/alkoxy sidechains has little impact on optical properties and energy levels, it can change crystal stacking motifs significantly. The single crystal of Y6‐1O with all linear sidechains forms a 2D‐brickwork structure and shows lower mobility. In contrast, 1OBO‐2 with all branched sidechains exhibits a favorable 3D interpenetrating porous network, displaying an electron mobility of 1.42 cm2 V−1 s−1 in single‐crystal organic field‐effect transistors (SC‐OFETs). This value is among the highest for NFA‐based n‐type OFETs. This study not only reveals the fundamental structure–property relationships of Y‐series NFAs, but also suggests the potential of Y‐series NFAs for high‐performance n‐type organic semiconductors. [ABSTRACT FROM AUTHOR]

A series of new π‐conjugated macrocycles (AzoM‐n‐E, n = 1–3) incorporating azobenzene units have been synthesized by a facile strategy in one‐pot reaction. The resultant azobenzene‐embedded macrocycles feature intrinsic photoresponsive behaviors and intriguing supramolecular assembling properties. The smallest macrocycle AzoM‐1‐E with a rigid planar conjugated backbone structure is used to prepare the single crystal transistors, showing reversible optical tunability. The moderate size macrocycle AzoM‐2‐E assembles into a dimer in the form of interpenetration through π‐π stacking between azobenzene units. The largest macrocycle AzoM‐3‐E with enhanced flexibility can adaptively assemble with various types of electron‐deficient guests accompanied by distortion of azobenzene. Typically, AzoM‐3‐E assembles with the planar F4‐TCNQ to form a tetragonal geometry by C‐F···π and π‐π interactions, while the assembly with ellipsoidal C70 via π‐π interactions induces AzoM‐3‐E to form a boat‐shaped geometry. This work will shed new light on the development of functional conjugated macrocycles in organic electronics. [ABSTRACT FROM AUTHOR]

Carbon nanorings (CNRs) and carbon nanobelts (CNBs) of various sizes and innovative molecular architectures have ushered improvement in research in recent years. This serves as a prerequisite for further advances and applications, such as organic semiconductors and bottom‐up synthesis of single‐walled carbon nanotubes. Nevertheless, challenges such as high strain energy, excessive reactivity, end‐product stability, low‐scale yields, and side reactions inhibit material synthesis and applications. In this review, CNRs, CNBs, and other heteroatom‐doped molecular belts are discussed based on their molecular structural characteristics, with a special focus on their developments in the past two years. Furthermore, current applications, research obstacles, and future developments related to CNRs and CNBs are discussed. For the first time, studies and advancements in organic field‐effect transistors (OFETs) have been summarized in detail. [ABSTRACT FROM AUTHOR]

Large‐area continuous covalent organic frameworks (COFs) film is highly desirable for the large‐scale continuous selective photocatalytic coupling of benzylamine (BA); however, traditional synthetic methods for preparing COFs films still suffer from the issues of harsh reaction condition, film breakage, and high energy‐consumption. Herein, a room‐temperature strategy is reported for making large‐area continuous imine‐based COFs film through the "infiltration‐reaction‐assembly" mechanism, demonstrating that such strategy is quite universal for making four types of large‐area COFs films. The as‐made PyTTA‐TPA (PyTTA: 1，3，6，8‐tetrakis(4‐aminophenyl)pyrene, TPA: p‐benzaldehyde) COFs film exhibits excellent catalytic performance for selective photocatalytic coupling of benzylamine (BA) with a high conversion rate of 98.2% and high selectivity of 97% in 3 h, which is the best photocatalytic performance in all reported photocatalysts. In addition, the as‐made COFs film is quite general for achieving photocatalytic coupling of other amine derivatives with outstanding photocatalytic performance of ≈100% conversion rate. Overall, this work brings a significant development for the room‐temperature synthesis of large‐area continuous COFs film to photocatalytic reaction. [ABSTRACT FROM AUTHOR]

A family of novel highly π‐extended tetracyano‐substituted acene diimides, named as tetracyanodiacenaphthoanthracene diimides (TCDADIs), have been synthesized using a facile four‐fold Knoevenagel condensation strategy. Unlike conventional cyano substitution reactions, our approach enables access to a large π‐conjugated backbone with the in‐situ formation of four cyano substitutents at room temperature while avoiding extra cyano‐functionalization reactions. TCDADIs decorated with different N‐alkyl substituents present good solubility, near‐coplanar backbones, good crystallinity, and low‐lying lowest unoccupied molecular orbital energies of −4.33 eV, all of which contribute to desirable electron‐transport performance when applied in organic field‐effect transistors (OFET). The highest electron mobility of an OFET based on a 2‐hexyldecyl‐substituted TCDADI single crystal reaches 12.6 cm2 V−1 s−1, which is not only among the highest values for the reported n‐type organic semiconductor materials (OSMs) but also exceeds that of most n‐type OSMs decorated with imide units. [ABSTRACT FROM AUTHOR]

A family of novel highly π‐extended tetracyano‐substituted acene diimides, named as tetracyanodiacenaphthoanthracene diimides (TCDADIs), have been synthesized using a facile four‐fold Knoevenagel condensation strategy. Unlike conventional cyano substitution reactions, our approach enables access to a large π‐conjugated backbone with the in‐situ formation of four cyano substitutents at room temperature while avoiding extra cyano‐functionalization reactions. TCDADIs decorated with different N‐alkyl substituents present good solubility, near‐coplanar backbones, good crystallinity, and low‐lying lowest unoccupied molecular orbital energies of −4.33 eV, all of which contribute to desirable electron‐transport performance when applied in organic field‐effect transistors (OFET). The highest electron mobility of an OFET based on a 2‐hexyldecyl‐substituted TCDADI single crystal reaches 12.6 cm2 V−1 s−1, which is not only among the highest values for the reported n‐type organic semiconductor materials (OSMs) but also exceeds that of most n‐type OSMs decorated with imide units. [ABSTRACT FROM AUTHOR]

Biomarkers are primary indicators for precise diagnosis and treatment. The early identification of health biomarkers has been sustained by the evolutionary success in sensor technologies. Among them, graphene field‐effect transistor (GFET) biosensors have exhibited major advantages such as an ultrashort response time, high sensitivity, easy operation, capability of integration, and label‐free detection. Owing to the atomic thickness, graphene restricts charge carrier flow merely at the material surface and responds to foreign stimuli directly, leading to effective signal acquisition and transmission. Here, this review summarizes the latest advances in GFET biosensors in a comprehensive manner that contains the device design, working principle, surface functionalization, and proof‐of‐concept applications. It provides a comprehensive survey of GFET biosensors with regard to biomarker analysis at the single‐device level and integrated prototypes that include wearable sensors, biomimetic systems, healthcare electronics, and diagnostic platforms. Moreover, there is discussion on the long‐standing research efforts and outlook for the future development of GFET sensor systems from lab to fab. [ABSTRACT FROM AUTHOR]

In this paper, a simple cationic exchange method was proposed to increase the Co/Mo ratio in the Evans‐Showell polyoxometalate to the desired 0.5 with both Mo and Co atoms in one molecule. This approach was proved successfully by X‐ray diffraction, X‐ray fluorescence spectrometer, infrared spectroscopy, and thermogravimetric analyzer. Then, the obtained Evans‐Showell‐type polyoxometalate was used as a superior precursor to construct efficient hydrodesulfurization catalyst, and the dibenzothiophene evaluation results showed that the hydrodesulfurization reaction turnover frequency, the rate constant, and the dibenzothiophene conversion are 1.8×10−3 s−1, 6.4×10−7 mol g−1 s−1, and 95.2 %, respectively, illustrating the excellent hydrodesulfurization performance of the catalyst. The cationic exchange approach promises the Mo and Co atoms in one molecule and the desired proximity of them, leading to a higher dispersion of MoS2 nanoparticles, a higher percent of CoMoS active phase and the excellent hydrodesulfurization performance for dibenzothiophene consequently. [ABSTRACT FROM AUTHOR]

The emulation of functions and behaviors of biological synapses using electronic devices has inspired the development of artificial neural networks (ANNs) in biomedical interfaces. Despite the achievements, artificial synapses that can be selectively responsive to non‐electroactive biomolecules and directly operate in biological environments are still lacking. Herein, we report an artificial synapse based on organic electrochemical transistors and investigate the selective modulation of its synaptic plasticity by glucose. The enzymatic reaction between glucose and glucose oxidase results in long‐term modulation of the channel conductance, mimicking selective binding of biomolecules to their receptors and consequent long‐term modulation of the synaptic weight. Moreover, the device shows enhanced synaptic behaviors in the blood serum at a higher glucose concentration, which suggests its potential application in vivo as artificial neurons. This work provides a step towards the fabrication of ANNs with synaptic plasticity selectively mediated by biomolecules for neuro‐prosthetics and human‐machine interfaces. [ABSTRACT FROM AUTHOR]

For epidemic prevention and control, molecular diagnostic techniques such as field‐effect transistor (FET) biosensors is developed for rapid screening of infectious agents, including Mycobacterium tuberculosis, SARS‐CoV‐2, rhinovirus, and others. They obtain results within a few minutes but exhibit diminished sensitivity (<75%) in unprocessed biological samples due to insufficient recognition of low‐abundance analytes. Here, an electro‐enhanced strategy is developed for the precise detection of trace‐level infectious agents by liquid‐gate graphene field‐effect transistors (LG‐GFETs). The applied gate bias preconcentrates analytes electrostatically at the sensing interface, contributing to a 10‐fold signal enhancement and a limit of detection down to 5 × 10−16 g mL−1 MPT64 protein in serum. Of 402 participants, sensitivity in tuberculosis, COVID‐19 and human rhinovirus assays reached 97.3% (181 of 186), and specificity is 98.6% (213 of 216) with a response time of <60 s. This study solves a long‐standing dilemma that response speed and result accuracy of molecular diagnostics undergo trade‐offs in unprocessed biological samples, holding unique promise in high‐quality and population‐wide screening of infectious diseases. [ABSTRACT FROM AUTHOR]

Although the effects of electron‐deficient group substitution on isoindigo on the corresponding conjugated polymers are extensively studied, the modification of isoindigo core with electron‐rich groups has not been investigated. It is envisioned that the introduction of the methoxy group on isoindigo will not only tune the highest occupied molecular orbital (HOMO) energy level of the corresponding polymers but also introduce O···S "conformation lock" to increase the coplanarity of the polymers, which should facilitate hole transport. Herein, the syntheses of two methoxylated isoindigos and the investigations on the charge transport behaviors of their copolymers with bisthiophene (2T) and bisthiazole (2Tz) are reported. It is found that the substitution positions have a drastic influence on the UV–vis absorption and electrochemical properties for both monomers and polymers. Theoretical calculations and single crystal structure analysis confirm the existence of O···S "conformation lock", however, both methoxy substitutions also change the aggregation behaviors of the corresponding polymers to a mixed face‐on/edge‐on orientation which has an adverse effect for charge transport. Among the four polymers, the polymer of 5,5'‐methoxylated isoindigo and 2T exhibit the best hole mobility of 1.9 × 10−1 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

Highly aligned aggregation state structures have great significance for effective charge‐carrier transport in organic semiconductors. Several methods have been developed to provide organic semiconducting molecules with highly oriented aggregation state structure; among these, using a water surface to form organic semiconductor films is a widely implemented strategy, wherein solutions are spread on the surface of water. However, common techniques of film formation on water surfaces generally result in a nonuniform orientation of the film owing to the isotropic spread process of droplets on the water surface. In this study, a spatially confined air/water interfacial assembly method is proposed to obtain uniformly aligned monolayer and multilayer poly(diketopyrrolopyrrole‐thieno[3,2‐b]thiophene) thin films with controlled thickness. The structural and morphological characterizations obtained using atomic force microscopy, high‐resolution transmission electron microscopy, and grazing incidence wide‐angle X‐ray scattering indicates the crystalline structure of the thin films and high alignment of the molecular chains. The maximum mobility of the thin films reaches up to 2.06 and 0.5 cm2 V−1 s−1 in the parallel and perpendicular direction, respectively, indicating apparent anisotropic electrical properties. Furthermore, an inverter based on these thin films exhibits a voltage gain of up to 70, demonstrating the potential of applying the proposed technique to logic circuits. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: 2D covalent organic framework (2D‐COF), a modular three‐dimensional material, is easily influenced by the component module. The assembly of different functionalized modules gives 2D‐COF unique performance. The modular structure not only allows for customization but also allows for variety, which gives 2D‐COF a wide range of functions. Hence, many building blocks with catalytic, ligand, semiconductor, luminescent, and redox centers are integrated into the COF scaffold. The connection and assembly of such modules determine the nature of the final block material. The intra‐layer connections of the modules form a monolayer mesh chemical structure, and the subsequent stacking of the monolayer mesh structure produces the final crystalline porous material—2D‐COF. This review describes in detail the potential of COF materials as optoelectronic materials and our understanding of optoelectronic processes, starting from monolayer reticulation chemistry to final 3D stacked structures, thus establishing a new paradigm for the rational design of well‐defined novel 2D‐COF optoelectronic materials and devices. [ABSTRACT FROM AUTHOR]

Artificial sensory nerves can simulate the functions of visual perception and information processing of the human brain, which is indispensable for the immediate visualization of the environment and awareness requisite to avoid the potential harm. However, it still remains a long‐standing challenge to integrate recognition learning with real‐time processing function in a single device. Herein, an interface defects‐tuning strategy is proposed for developing a novel bi‐functional phototransistor. Benefiting from the tuned polymer‐perovskite layer‐heterointerface defects, the photogenerated charge trapping and de‐trapping capacities are significantly improved, thereby facilitating the photogenerated carrier separation and injection. The prepared organic‐inorganic hybrid phototransistors can perfectly mimic the human visual synaptic behaviors with a quick response speed (<35 ms, far below that of human eyes to incident light (225 ms)). More importantly, the phototransistor exhibited obvious visual adaptation toward wide‐ranging light stimuli, and realized unique desensitization to simulate the self‐protection behavior of the human visual systems. Specifically, the adaptation timescales of the device under dim and high light conditions are superior to bio‐systems (<2 min). Consequently, the reported strategy for the preparation of bi‐functional phototransistors provides a brand‐new perspective for next‐generation artificial nervous systems. [ABSTRACT FROM AUTHOR]

The modulation effect manifests an encouraging potential to enhance the performance of single‐atom catalysts; however, the in‐depth study about this effect for the isolated diatomic sites (DASs) remains a great challenge. Herein, a proximity electronic effect (PEE) of Ni/Co DASs is proposed that is anchored in N‐doped carbon (N‐C) substrate (NiCo DASs/N‐C) for synergistic promoting electrocatalytic oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER). Benefiting from the PEE of adjacent Ni anchored by four nitrogen (Ni‐N4) moiety, NiCo DASs/N‐C catalyst exhibits superior ORR and HER activity. In situ characterization results suggest Co anchored by four nitrogen (Co‐N4) as main active site for O2 adsorption‐activation process, which promotes the formation of key *OOH and the desorption of *OH intermediate to accelerate the multielectron reaction kinetics. Theoretical calculation reveals the adjacent Ni‐N4 site as a modulator can effectively adjust the electronic localization of proximity Co‐N4 site, promoting the *OH desorption and *H adsorption on Co‐N4 site, thereby boosting ORR and HER process significantly. This study opens a new opportunity for rationally regulating the electronic localization of catalytic active centers by proximity single‐atom moiety, as well as provides guidance for designing high‐efficiency bifunctional electrocatalysts for promising applications. [ABSTRACT FROM AUTHOR]

Ladder‐like aromatic diketones (LADK), which possess a coplanar π‐extended geometry, a high electron deficiency as well as various attractive optoelectronic properties, are demonstrated as the promising candidates in building small‐molecule organic electron‐transporting materials, yet reports on direct integration of these structural motifs into n‐type polymers are rarely accessed. Herein, it is demonstrated that a possibility of realizing unipolar n‐type characteristics of such acceptor system by developing two novel donor–acceptor type polymers, in which the newly developed LADK unit, named as 3,8‐bis(2‐decyltetradecyl)‐5,10‐difluoro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐4,9‐dione (FIDTO‐R), is adopted as the acceptor segments. The resulting polymers present deep‐lying unoccupied molecular orbital levels (as low as −3.84 eV), compact π–π stacking (d‐spacing, ≈3.57 Å) coupled with uniform nanofiber‐like surface morphology. All these factors contribute to excellent unipolar n‐type characteristics with high electron mobilities of 0.27 and 1.01 cm2 V−1 s−1, together with high inverter gain values of 141 and 80, respectively. The recorded values are among the best in n‐type polymer field‐effect transistors and associated inverter circuits. These findings unambiguously reveal that the as‐prepared FIDTO‐R and its analog LADK derivatives are another type of excellent building blocks for the construction of high‐mobility n‐type polymers. [ABSTRACT FROM AUTHOR]

Flexible organic monitoring system that can work in short‐wave infrared (SIR) region has great potential in autonomous driving, night driving safety, military encryption, biomedical imaging, and robot engineering. Especially, the development of infrared artificial vision system device that can autonomously improve the computing speed and adapt to different brightness ambient light is very important. However, it is a challenge for mimicking infrared visual adaptation because of the need for infrared absorbing materials and the need to control the concentration of carriers. In this study, inorganic quantum dot material is combined with organic materials to promote carrier separation and introduce interface defects that adjust the carrier concentration in transistors, which induce the synaptic behavior under SIR (1100 nm) light in darkness and the ability to adapt to white ambient light. Furthermore, the device array realizes the image recognition of SIR light at night with white ambient light of different brightness, exhibiting good self‐adaptability, and strong anti‐interference ability. These results demonstrate promising applications of the infrared synaptic phototransistors in adapted bionic optoelectronic devices. [ABSTRACT FROM AUTHOR]

The development of polymer semiconductors with strong luminescence and high mobility has always been challenging, and achieving both properties together is considered paradoxical according to molecular design principles. Studies on novel molecular species with unique optoelectrical characteristics are limited. Herein, a novel fully rigid coplanar thiophene‐pyridal[1,2,3]triazole‐thiophene (T‐PT‐T) class structure with considerable intramolecular noncovalent interactions is proposed. To balance luminescence and carrier transport properties, a series of non‐conventional regioregular conjugated polymers (PPTs) with suitable energy gaps (Egs ≈ 1.8 eV) are developed, which exhibit near‐infrared (NIR, 700–1000 nm) light emission and high mobility. One of the synthesized polymers, PPT‐2, exhibits an excellent photoluminescence quantum yield (PLQY) of 9% in the solid‐state and a high mobility reaching 0.35 cm2 V−1 s−1, indicating superior performance compared to other NIR light‐emitting polymer semiconductors. The authors believe that the class structure of fully rigid coplanar "T‐PT‐T" could be harnessed to develop high‐mobility NIR light‐emitting polymer semiconductors. [ABSTRACT FROM AUTHOR]

Numerous studies conducted on the layered graphene family—including the monolayer, bilayer, trilayer, few‐layer, and multilayer—draw plenty of attention to stacking modes and twist angles, which are extensively explored for its controlled growth, properties, and applications. This review provides a comprehensive overview of current challenges and opportunities for the chemical vapor deposition (CVD) growth, characterization, and electrical properties of graphene depending on the layer number and twist angles. Various state‐of‐the‐art innovations using the CVD method, which incorporates graphene synthesis through the control of metal substrates, layer numbers, and twist angles, are presented. The underlying growth mechanisms are discussed in terms of the interactions among graphene substrates/layers and its dynamic process. The characterization methods for determining the layer number and twist angle of graphene layers are summarized. Furthermore, the electrical properties and applications of graphene, particularly magic‐angle twist bilayer graphene, are briefly introduced. Finally, outlooks and perspectives for the engineering of CVD graphene layers are discussed. [ABSTRACT FROM AUTHOR]

BACKGROUND: Vitis vinifera L. cv. Syrah grapevines in most Chinese viticulture regions generally have compact clusters that increase the susceptibility to diseases and inhibit coloration of the inner berries. Gibberellic acid (GA3) is a plant growth regulator that is widely used during grape cultivation to elongate the rachis, control fruit set, and decrease cluster compactness. In this study, Syrah grapevines were treated with GA3 before flowering in 2019 and 2020 to determine the optimal GA3 treatment concentrations and times for decreasing bunch compactness, while minimizing the negative effects on the wine grape cluster weight. RESULTS: Pre‐flowering GA3 applications at 3, 5, and 7 mg L−1, especially treatment at 20 days before flowering, decreased Syrah grape bunch compactness by decreasing the fruit set rate and promoting bunch elongation, with minimal adverse effects on the healthy grape cluster weight in both years. The 7 mg L−1 GA3 treatment at 20 days before flowering significantly increased reducing sugar, total phenolic, tannin, and total anthocyanin contents of Syrah grape berries in 2019 and 2020. Moreover, high‐performance liquid chromatography–electrospray ionization–tandem mass spectrometry, hierarchical cluster, and principal component analysis results indicated GA3 applications before flowering (3, 5, and 7 mg L−1) significantly affected the accumulation of different anthocyanins in Syrah grape berries. Notably, the application of 7 mg L−1 GA3 at 20 days before flowering resulted in the highest anthocyanin content. CONCLUSION: Pre‐flowering gibberellin application can decrease bunch compactness and improve the quality of Syrah grape berries. These findings reflect the potential utility of gibberellin treatments for decreasing cluster compactness and increasing the quality of wine grapes. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Solution‐processing approaches are widely used for controlling the aggregation structure of organic semiconductors because they are fast, efficient, and have strong practicability. Effective regulation of the aggregation structure of molecules to achieve highly ordered molecular stacking is key to realizing effective carrier transport and high‐performance devices. Numerous studies have achieved highly aligned organic semiconductors using different solution‐processing approaches. This article provides a detailed review of the prevalent solution‐processing technologies and emerging methods developed over the past few years for the alignment of organic semiconducting materials. These technologies and methods are classified according to the processing principle. This review focuses on the principles of different experimental techniques, improvements upon the conventional methods, and state‐of‐the‐art performance of resulting devices. In addition, a brief discussion of the characteristics and development prospects of various methods is presented. [ABSTRACT FROM AUTHOR]

Organic field‐effect transistor (OFET)‐based circuits require stable device performance. However, OFETs are suffering from process variation and environmental instability, which limits circuit performance. Here, an optimally designed XOR gate based on p‐type‐only OFETs is reported. The circuit has excellent postfabrication tunability that is enough to cope with a threshold voltage shift as high as 1.5 V. Moreover, the circuit largely reduces the number of transistors by 81% compared with conventional design and can realize ultralow power consumption. In addition, the XOR gate can act as a programmable inverter with good regenerative property. Utilizing the XOR gate, the authors demonstrate its application in cryptography. A 3481‐bit message is correctly encrypted and decrypted with an accuracy rate of up to 98.5%. The authors' work enables the accurate prediction of circuit operation in the presence of OFET threshold voltage shifts. [ABSTRACT FROM AUTHOR]

Cu‐benzenehexathiol (Cu‐BHT) has attracted significant attention due to its record high electrical conductivity and crystal defects Cu2c. However, the nonporous structure and small specific surface area of Cu‐BHT with two‐dimensional kagome lattice invariably limit its practical application in sensing and catalysis. In this work, Cu‐BHT nanotubes (Cu‐BHT‐NTs) are designed and prepared via a facile homogeneous reaction to solve these problems. Compared with the traditional nanorod‐like structure, the Cu‐BHT‐NTs not only have a higher specific surface area but also possess a higher proportion of crystal defects (66.6%). The successfully configured DPPTT/Cu‐BHT‐NTs heterostructure organic field‐effect transistor (OFET)‐based sensor exhibits excellent sensitivity as high as 13 610%, a minimum detection limits down to 5 ppb, and exceptional selectivity to nitric oxide (NO) toxic gases. Theoretical analysis systematically shows that Cu2c sites in the Cu‐BHT‐NTs increase the number of electrons transferred from the heterostructure to NO molecules, confirming that the high sensitivity and selectivity result from the high binding between Cu‐BHT‐NTs and NO molecules. Furthermore, a fully flexible device based on the heterojunction OFET sensor is prepared to ensure the convenience of wearing and carrying gas sensors, opening up a new avenue for the next generation of wearable intelligent electronics. [ABSTRACT FROM AUTHOR]

The molecular packing and resultant charge transport behaviors of semiconducting polymers are widely known to be temperature‐dependent. Due to the limitation of measurement methods, previous studies on molecular packing behavior have been mainly focused on a very limited temperature range, and therefore cannot support the understanding of charge transport behaviors. In this study, with a homemade temperature‐dependent grazing incidence XRD measurement chamber, the relationship between molecular packing structure and charge transport properties of diketopyrrolopyrrole‐based polymers is investigated across a wide temperature range of 98–623 K. Glass transition temperatures of the alkyl side‐chain and aromatic backbone are identified through the observation of clear transitions in the thermal expansion coefficients of d−d packing and π−π stacking, respectively. A correlation between the π−π stacking distance and charge transport properties is then established using an extended Miller−Abrahams model. The turning point of the charge transport and the failure of the polymer‐based devices are proved to be caused by packing structure changes due to increased temperatures. Such an examination over a wide range of temperatures improves the understanding of the charge transport properties of semiconducting polymers and helps construct thermally stable devices to be used in extreme conditions. [ABSTRACT FROM AUTHOR]

Robust 2‐mm 6061‐T6/SUS304 butt plates were obtained using laser‐MIG hybrid welding‐brazing technology. The fatigue properties and fracture behavior of Al/steel welding‐brazing joints were first discussed. Due to the change in the fracture mechanism, the weld reinforcement improved the fatigue strength, which was higher than that of the Al/steel joints using the solid‐state welding method. This strengthening effect was very different from traditional fusion welding joints with reinforcement. The fatigue test results showed that the fatigue strength of the Al/steel joints with reinforcement reached about 105 MPa at 106 cycles. After removing the weld reinforcement, the fatigue strength of the Al/steel joints reduced significantly to 55 MPa. The existence of reinforcement also led to different fatigue fracture behaviors. In the Al/steel joints with reinforcement, the fatigue fracture mode changed with increasing cyclic stress load, and the fatigue crack initiation zone was inclined to begin at the weld toe and then propagated along the weld at a lower stress load. Fatigue crack initiation sites moved to the aluminum weld near the interface and spread along with the IMC layer and the aluminum weld at higher stress loads. After removing the weld reinforcement, only the interface fracture mode was found. Highlights: A high strength Al/steel welding‐brazing joint (up to 200 MPa) is obtained.The weld reinforcement has a positive effect on the fatigue strength.The existence of the weld reinforcement leads to different fatigue fracture modes.Pores inside the aluminum weld are likely to be the fatigue crack initiation zone. [ABSTRACT FROM AUTHOR]