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In recent decades, polymer semiconductors, extensively employed as charge transport layers in devices like organic field‐effect transistors (OFETs), have undergone thorough investigation due to their capacity for large‐area solution processing, making them promising for mass production. Research efforts have been twofold: enhancing the charge mobilities of polymer semiconductors and augmenting their mechanical properties to meet the demands of flexible devices. Significant progress has been made in both realms, propelling the practical application of polymer semiconductors in flexible electronics. However, integrating excellent semiconducting and mechanical properties into a single polymer still remains a significant challenge. This review intends to introduce the design strategies and discuss the properties of high‐charge mobility stretchable conjugated polymers. In addition, another key challenge faced in this cutting‐edge field is maintaining stable semiconducting performance during long‐term mechanical deformations. Therefore, this review also discusses the development of healable polymer semiconductors as a promising avenue to improve the lifetime of stretchable device. In conclusion, challenges and outline future research perspectives in this interdisciplinary field are highlighted. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Isoindigo (IID) is widely used as organic dye and conjugated unit in opto‐electronic materials. Functionalization of IID to increase its structural complexity is demanding for obtaining diversity properties. Herein, we developed a direct C—H/N—H activation method of IIDs via double alkyne annulations and synthesized π‐extended IIDs with two pairs of 5/7 membered rings. The structure of the π‐extended IIDs was characterized and confirmed by 1H NMR, 13C NMR, HRMS and X ray crystal analysis. Their physical properties were characterized by UV‐vis absorption, cyclic voltammetry and thermogravimetric analysis. The absorption coefficient of the annulated products enhanced significantly compared with the non‐annulated analogue. [ABSTRACT FROM AUTHOR]

Non‐benzenoid polycyclic aromatic hydrocarbons (PAHs) have received a lot of attention because of their unique optical, electronic, and magnetic properties, but their synthesis remains challenging. Herein, we report a non‐benzenoid isomer of peri‐tetracene, diazulenorubicene (DAR), with two sets of 5/7/5 membered rings synthesized by a (3+2) annulation reaction. Compared with the precursor containing only 5/7 membered rings, the newly formed five membered rings switch the aromaticity of the original heptagon/pentagon from antiaromatic/aromatic to non‐aromatic/antiaromatic respectively, modify the intermolecular packing modes, and lower the LUMO levels. Notably, compound 2 b (DAR‐TMS) shows p‐type semiconducting properties with a hole mobility up to 1.27 cm2 V−1 s−1. Moreover, further extension to larger non‐benzenoid PAHs with 19 rings was achieved through on‐surface chemistry from the DAR derivative with one alkynyl group. [ABSTRACT FROM AUTHOR]

Emissive organic semiconductors are highly demanding for organic light‐emitting transistors (OLETs) and electrically pumped organic lasers (EPOLs). However, it remains a great challenge to obtain organic semiconductors with high carrier mobility and high photoluminescence quantum yield simultaneously. Here, a new design strategy is reported for highly emissive ambipolar and even n‐type semiconductors by introducing perfluorophenyl groups into polycyclic aromatic hydrocarbons such as perylene and anthracene. The results reveal that 3,9‐diperfluorophenyl perylene (5FDPP) exhibits the ambipolar semiconducting property with hole and electron mobilities up to 0.12 and 1.89 cm2 V−1 s−1, and a photoluminescence quantum yield of 55%. One of the crystal forms of 5FDPA exhibits blue emission with an emission quantum yield of 52% and simultaneously shows the n‐type semiconducting property with an electron mobility up to 2.65 cm2 V−1 s−1, which is the highest value among the reported organic emissive n‐type semiconductors. Furthermore, crystals of 5FDPP are utilized to fabricate OLETs by using Ag as source–drain electrodes. The electroluminescence is detected in the transporting channels with an external quantum efficiency (EQE) of up to 2.2%, and the current density is up to 145 kA cm−2, which are among the highest values for single‐component OLETs with symmetric electrodes. [ABSTRACT FROM AUTHOR]

Molecular probes which can be modulated, functionalized and used to visualize the processes are highly desirable for understanding and manipulating biological systems. Geometric cis and trans isomers of tetraphenylethene (TPE) emerge as attractive candidates to fulfill these tasks thanks to the unique aggregation‐induced emission properties, tailorable structures, and responsiveness to external stimuli. This minireview focuses on cis and trans isomers of TPE derivatives that are functionalized with molecular recognition units for fluorescence detection, bioimaging and cancer therapy. The effects of molecular geometry on fluorescence property, target binding ability and biological activity are summarized. The feasibility to in vitro and in vivo switch molecular configuration and thus bio‐activity is discussed. Finally, the future development and challenges are discussed in view of TPE‐based stereoisomers for targeted sensing and imaging‐guided modulation of biological processes. [ABSTRACT FROM AUTHOR]

Non‐benzenoid acenes containing heptagons have received increasing attention. We herein report a heptacene analogue containing a quinoidal benzodi[7]annulene core. Derivatives of this new non‐benzenoid acene were obtained through an efficient synthetic strategy involving an Aldol condensation and a Diels–Alder reaction as key steps. The configuration of this heptacene analogue can be modulated from a wavy to a curved one by just varying the substituents from a (triisopropylsilyl)ethynyl group to a 2,4,6‐triisopropylphenyl (Trip) group. When mesityl (Mes) groups are linked to the heptagons, the resulting non‐benzenoid acene displays polymorphism with a tunable configuration from a curved to a wavy one upon varying the crystallization conditions. In addition, this new non‐benzenoid acene can be oxidized or reduced by NOSbF6 or KC8 to the respective radical cation or radical anion. Compared with the neutral acene, the radical anion shows a wavy configuration and the central hexagon becomes aromatic. [ABSTRACT FROM AUTHOR]

Organic room‐temperature phosphorescence (RTP) materials have attracted much attention in recent years due to their potential applications. However, the development of organic RTP emitters with a long lifetime and high quantum yield remains a great challenge owing to the weak molecular spin–orbit coupling and high sensitivity to oxygen. In this paper, a new purely organic RTP emitter, 3,3″,4,4″‐diphenylsulfonetetracarboxylic dianhydride (DPS), is reported which shows an excitingly ultralong lifetime up to 1.08 s and high phosphorescence quantum yield of 8%. When anhydride units in DPS are transformed into imides, the RTP performance in terms of lifetime and quantum yield is decreased. The presence of multiple intermolecular interactions is favorable for the restriction of nonradiative decay and the promotion of spin–orbit coupling, which is further corroborated by theoretical calculations. The studies demonstrate that DPS is a promising structural motif for developing high‐performance organic RTP emitters. [ABSTRACT FROM AUTHOR]

We herein report a phosphoric‐acid‐substituted tetraphenylethene (T‐P) capable of adapting its geometric configuration and biological activity to the microenvironment upon light irradiation for apoptosis modulation. Different from most ultraviolet‐responsive isomerization, T‐P undergoes cis‐trans isomerization under visible light irradiation, which is biocompatible and thus photo‐modulation is possible in living biosystems. By using alkaline phosphatase (ALP) and albumin as dual targets, T‐P isomers display different protein binding selectivity, cancer‐cell internalization efficiency and apoptosis‐inducing ability. The proapoptotic activity was found to be kinetically controlled by the enzymatic reaction with ALP and regulated by co‐existing albumin. Motivated by these findings, two‐way modulation of proapoptotic effect and on‐demand boosting anticancer efficacy were realized in vitro and in vivo using light and endogenous proteins as multiple non‐invasive switching stimuli. [ABSTRACT FROM AUTHOR]

Herein, single‐molecule conductance studies of TBT1‐TBT6 which entails 1,4‐dithienylbenzene as the backbone and SMe groups as the anchoring units, with the scanning tunneling microscope break junction (STM‐BJ) technique, are reported. The molecular conductance of TBT1 with intramolecular O•••S noncovalent interactions is enhanced by about one order of magnitude in comparison to their analogue TBT2 (which contains alkyl instead of alkoxy chains). By replacing the methoxy groups in TBT1 with extending alkoxy chains in TBT3, TBT4, and TBT5, the molecular backbones become twisted and as a consequence the single‐molecule conductance decreases gradually, showing that the intramolecular O•••S noncovalent interaction is influenced by the structural features of alkoxy chains. More importantly, the single‐molecule conductance of TBT3, TBT4, and TBT5 can be boosted by increasing the electric field applied to the molecular junctions. Remarkably, the conductance of TBT3, TBT4, and TBT5 can be reversibly modulated due to the conformational changes between twisted and planar ones by varying the electric field. These results demonstrate that molecules with intramolecular O•••S noncovalent interactions have the potential for in situ control of the electrical properties of molecular‐scale devices. [ABSTRACT FROM AUTHOR]

Multiple relaxation behaviors are promising for broad frequency band and strong electromagnetic wave (EMW) absorption based on polarization‐controlled electromagnetic (EM) attenuation. However, rational selection of materials and structure manipulation through tunable substitution or phase control are challenging toward optimization of EMW absorption. Herein, bi‐metallic organic frameworks (B‐MOFs) with various morphologies are employed as EMW absorbers. Remarkably, the polar units can be enhanced by introducing Ni‐metal nodes into the Cu‐coordinated MOFs, rendering the B‐MOFs with self‐polarized properties and consecutive multifrequency EMW absorption behaviors. The maximum reflection loss of acetylene black (ACET) filled NiCu‐MOFs can reach –40.54 dB together with a wide bandwidth (<‐10 dB) of 5.87 GHz at a thickness of 2.5 mm. As a counterpart of the Ni/Cu/C derivatives, significantly increased broad band absorption (6.93 GHz) and multifrequency absorbing and polarization characteristics are also maintained in bimetal coexisting carbonized architectures as prepared by calcination of CuNi‐MOFs. This work demonstrates that the performance of effective absorbing frequency band can be enhanced in multi‐metallic organic frameworks‐based architectures, and paves a novel avenue for developing broadband and strong EMW absorbers. [ABSTRACT FROM AUTHOR]

Vigorous development of 5G communication technologies can boost mobile networks yet bring in electromagnetic interferences and safety concerns in utilizing electronic devices. Particularly, 5G network can not only involve a low‐frequency band of n78 (3.3–3.8 GHz) but also cover multi‐frequency bands of n77 (3.3–4.2 GHz) and n79 (4.4–5.0 GHz), displaying multiple electromagnetic radiations. Countless efforts have been devoted to investigating electromagnetic wave (EMW) absorbers with low‐ and multi‐band absorption properties. However, in terms of emerging materials and designs, few reports propose the mechanisms related to those properties. This perspective briefly reviews the impressive achievements of low‐ and multi‐frequency EMW absorbers and analyzes the design strategies that may enable low‐ and multi‐frequency absorption. Furthermore, the cutting‐edge mechanisms of corresponding electromagnetic responses, such as Snoek limit, quarter wavelength, and dielectric‐magnetic synergy effects are elaborated. Thus, this perspective can shed light on the new trends and ongoing challenges for EMW absorbers and further promote their practical application. [ABSTRACT FROM AUTHOR]

Molecular systems that can function as photoresists are essential for the fabrication of flexible electronics through all‐photolithographic processes. Most of the reported molecular systems for photo‐patterning of polymeric semiconductors contain binary or multi‐components. In comparison, single component semiconducting photoresist is advantageous since it will circumvent the optimization of phase separation and ensure the patterned semiconducting thin films to be more uniform. In this paper, a single component semiconducting photoresist (PDPP4T‐N3) by incorporating azide groups into the branching alkyl chains of a diketopyrrolopyrrole‐based conjugated polymer is reported. The results reveal that i) the azide groups make the side chains to be photo‐cross‐linkable; ii) uniform patterns with size as small as 5 µm form under mild UV irradiation (365 nm, 85 mW cm−2) at ambient conditions; iii) such photo‐induced cross‐linking does not affect the inter‐chain packing; iv) benefiting from the single component feature, field‐effect transistors (FETs) with the individual patterned thin films display satisfactorily uniform performances with average charge mobility of 0.61 ± 0.10 cm2 V–1 s–1 and threshold voltage of 3.49 ± 1.43 V. These results offer a simple yet effective design strategy for high‐performance single component semiconducting photoresists, which hold great potentials for flexible electronics processed by all‐photolithography. [ABSTRACT FROM AUTHOR]

Development of pure organic molecular materials with room temperature phosphorescence (RTP) and their applications for white emitters have received significant attentions recently. Herein, a D–π–A molecule (DMACPPY) which can realize white emitting under ambient conditions both in the crystal state and the doped‐film state by combining RTP with two fluorescent emissions is reported. The white emission from the crystalline sample of DMACPPY consists fluorescence from S2 (the second excited singlet state) and S1 (the first excited singlet state) along with RTP from T1 (the first excited triplet state), namely, SST‐type white light. While, the white emission from the poly methyl methacrylate (PMMA) film doped with DMACPPY contains fluorescences from S2 and S1, and RTP from T2 (the second excited triplet state) rather than T1 (STS type). DMACPPY cannot exhibit white spectrum within alternative crystalline state since inferior RTP intensity despite similar ternary emissions. The results demonstrate that the emissive properties for excited states of DMACPPY can be tuned by changing the aggregate state from crystalline to dispersion state in PMMA film. This new RTP emitter fulfills the talent for white emitting and achieves dual‐mode white emissions, invisibly, expands the application range for pure organic and heavy atom‐free RTP materials. [ABSTRACT FROM AUTHOR]

VB‐Group transition metal disulfides (TMDs) are considered excellent materials for electromagnetic wave (EMW) absorption because of their good conductivity and abundant active sites located at their edges and substrates, as compared with VIB‐Group TMDs. Herein, for the first time, EMW absorbers based on VB‐Group NbS2 nanosheets by using a facile one‐step solvothermal method are successfully prepared. The minimum reflection loss (RLmin) can reach up to 43.85 dB with an effective absorption bandwidth of 6.48 GHz (11.52–18.00 GHz). The remarkable EMW absorption performance can also be reflected in the tunable frequency bands (C‐, X‐, and Ku‐bands), which is achieved by adjusting the contents of materials. Furthermore, the influence of the content of 2H‐phase and 1T‐phase in NbS2 on the EMW absorption performance is systematically investigated. The hierarchical hollow‐sphere structure of NbS2 promotes dielectric loss and the multiple reflection and absorption of EMW, and enhances the impedance matching and synergistic attenuation ability. This work demonstrates that the bottleneck of effective absorbing frequency band of single‐component dielectric EMW absorbing materials could be broken through, and paves a novel path towards developing broadband absorbing materials in EMW absorption. [ABSTRACT FROM AUTHOR]

A diazirine‐based four‐armed cross‐linker (4CNN) with a tetrahedron geometry is presented for efficient patterning of polymeric semiconductors by photo‐induced carbene insertion. After blending of 4CNN with no more than 3 % (w/w), photo‐patterning of p‐, n‐, and ambipolar semiconducting polymers with side alkyl chains was achieved; regular patterns with size as small as 5 μm were prepared with appropriate photomasks after 365 nm irradiation for just 40 s. The interchain packing order and the thin film morphology were nearly unaltered after the cross‐linking and the semiconducting properties of the patterned thin films were mostly retained. A complementary‐like inverter with a gain value of 112 was constructed easily by two steps of photo‐patterning of the p‐type and n‐type semiconducting polymers. The results show that 4CNN is a new generation of cross‐linker for the photo‐patterning of polymeric semiconductors for all‐solution‐processible flexible electronic devices. [ABSTRACT FROM AUTHOR]

The soft nature has endowed conjugated polymers with promising applications in a wide range of field‐effect transistor (FET) based flexible electronics. With unremitting efforts on revealing the molecular structure–property relationships, numerous novel conjugated polymers with high mobility and excellent mechanical property have been developed in the past decades. Incorporating hydrogen‐bonding (H‐bonding) units into semiconducting polymers is one of the most successful strategies for designing high‐performance semiconducting materials. In this review, we aim to highlight the roles of H‐bonding units in the performances of polymeric FETs from three aspects. These include (i) charge mobility enhancement for semiconducting polymers after incorporation of H‐bonding units into the side chains, (ii) the effects of H‐bonding units on the stretchability of conjugated polymers, and (iii) the improvement of self‐healing properties of conjugated polymers containing dynamic hydrogen bonds due to the H‐bonding units in the side chains or conjugated backbones. [ABSTRACT FROM AUTHOR]

Diketopyrrolopyrrole (DPP) as a building block has been intensively investigated for organic semiconductors and light emitting materials. The synthesis of N‐aryl DPPs remains challenging. Herein, we firstly report a new easily handled synthetic method toward N‐aryl DPPs through H‐DPP with diaryliodonium salt in the presence of CuI, which shows broad reaction scope. Sixteen N‐aryl DPPs, including phenyl, furan and thiophene as flanking aromatic groups, were synthesized with yields up to 78 %. These N‐aryl DPPs are fluorescent in both solutions and solid states, with quantum yields up to 96 % and 40 %, respectively. Moreover, we show that the reaction between H‐DPP and diaryliodonium salt can lead to π‐expanded DPPs by using Pd(OAc)2 as catalyst. Nine π‐expanded DPPs were obtained in 27–61 % yields. These π‐expanded DPPs exhibit good semiconducting properties with hole mobility of 0.71 cm2 V−1 s−1, demonstrating that they are useful building blocks for high performance organic semiconductors. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: The development of selenophene‐flanked DPP (SeDPP) based copolymers, especially for the ambipolar ones, lags behind other aromatic group flanked DPP‐based polymers. Herein, we report two new ambipolar SeDPP‐based conjugated polymers. One is the alternating polymer PSeDPPFT with normal SeDPP and 3,4‐difluorothiophene units. The other is PSeFDFT, in which the electron acceptor unit is replaced by a new SeDPP derivative, referred as to half‐fused SeDPP. The more planar structure of half‐fused SeDPP endows the backbone of PSeFDFT with good rigidity and planarity. Both polymers exhibit ambipolar transporting properties in air. The PSeFDFT based field‐effect transistors (FETs) display higher and more balanced ambipolar properties with μhave of 0.27 cm2·V–1·s–1, μeave of 0.18 cm2·V–1·s–1, and μhave/μeave of 1.5 than those of PSeDPPFT (μhave = 0.11 cm2·V–1·s–1, μeave = 0.042 cm2·V–1·s–1, and μh/μe = 2.6). This is attributed to the more planar structure, lower LUMO level, higher HOMO level, and better interchain packing orientations of PSeFDFT by comparing with PSeDPPFT. Therefore, a new molecular design strategy to modulate the hole and electron transporting properties is proposed for conjugated D‐A polymers. [ABSTRACT FROM AUTHOR]

Optically tunable field‐effect transistors (FETs) with near infra‐red (NIR) light show promising applications in various areas. Now, arylazopyrazole groups are incorporated in the side chains of a semiconducting donor–acceptor (D‐A) polymer. The cis–trans interconversion of the arylazopyrazole can be controlled by 980 nm and 808 nm NIR light irradiation, by utilizing NaYF4:Yb,Tm upconversion nanoparticles and the photothermal effect of conjugated D‐A polymers, respectively. This reversible transformation affects the interchain packing of the polymer thin film, which in turn reversibly tunes the semiconducting properties of the FETs by the successive 980 nm and 808 nm light irradiation. The resultant FETs display fast response to NIR light, good resistance to photofatigue, and stability in storage for up to 120 days. These unique features will be useful in future memory and bioelectronic wearable devices. [ABSTRACT FROM AUTHOR]

Tuning autophagy in a controlled manner could facilitate cancer therapy but it remains challenging. Pyridinium‐substituted tetraphenylethylene salts (PTPE 1—3), able to target mitochondria and disrupt autophagy after forming complexes with albumin, are reported. Mitochondrion affinity and autophagy‐inducing activity are improved by prolonging the length of alkyl chains in PTPE 1–3. PTPE 1–3 demonstrate proautophagic activity and a mitophagy blockage effect. Failure of autophagosome–lysosome fusion in downstream autophagy flux results in cancer cell death. Moreover, fast formation of complexes of PTPE 1–3 with albumin in blood can facilitate biomimetic delivery and deep tumor penetration. Efficient tumor accumulation and effective tumor suppression are successfully demonstrated with in vitro and in vivo studies. PTPE 1–3 salts exhibit dual functionality: they target and image mitochondria because of aggregation‐induced emission effects and they are promising for cancer therapy. [ABSTRACT FROM AUTHOR]

A novel building block, denoted as half‐fused diketopyrrolopyrrole (DPP) (9‐(3‐octadecylhenicosyl)‐8‐(thiophen‐2‐yl)‐7H‐pyrrolo[3,4‐a]thieno[3,2‐g]indolizine‐7,10(9H)‐dione), in which one of the flanking thiophene units is fused to one of the DPP rings via a carbon‐carbon double bond at the N‐position is reported. The half‐fused DPP is successfully utilized as an electron acceptor to prepare the conjugated donor–acceptor polymer PTFDFT, which exhibits ambipolar semiconducting behavior in ambient air. Theoretical calculations and absorption spectral studies show that the backbone of PTFDFT is more planar compared to the reference polymer with conventional DPP units. As a result, PTFDFT shows a narrow bandgap and low lowest unoccupied molecular orbital level. The more planar backbone with fewer side chains favors the dense packing of the polymer chains of PTFDFT with a short π–π stacking distance (3.49 Å). Grazing‐incidence wide‐angle X‐ray scattering data further confirm the predominant edge‐on packing mode of the PTFDFT polymer chains on the substrate. As expected, the PTFDFT thin film shows excellent ambipolar semiconducting properties under ambient conditions, reaching 2.23 and 1.08 cm2 V−1 s−1 for the n‐ and p‐channels, respectively. In addition, complementary‐like inverter with gain value as high as 141 is successfully constructed using the PTFDFT thin film. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons with hexagons/pentagons or hexagons/heptagons have been intensively investigated in recent years, but those with simultaneous presence of hexagons, pentagons and heptagons remain rare. In this paper, we report dicyclohepta[ijkl,uvwx]rubicene (DHR), a non‐benzenoid isomer of dibenzo[bc,kl]coronene with two pentagons and two heptagons. We developed an efficient and scalable synthetic method for DHR by using Scholl reaction and dehydrogenation. Crystal structure of DHR shows that the benzenoid rings, two pentagons and two heptagons are coplanar. The bond lengths analysis and the ICSS(1)zz and LOL‐π calculations indicate that the incorporation of two formal azulene moieties has an effect on the conjugated structure. The π‐electrons of benzenoid and pentagon rings are more delocalized. Cyclic voltammetry studies indicate that DHR shows multiple oxidation and reduction potentials. Interestingly, DHR exhibits unusual S0 to S2 absorption and abnormal anti‐Kasha S2 to S0 emission. Moreover, crystals of DHR exhibit semiconducting behaviour with hole mobility up to 0.082 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

The experimental investigation of intermolecular charge transport in π‐conjugated materials is challenging. Herein, we describe the investigation of charge transport through intermolecular and intramolecular paths in single‐molecule and single‐stacking thiophene junctions by the mechanically controllable break junction (MCBJ) technique. We found that the ability for intermolecular charge transport through different single‐stacking junctions was approximately independent of the molecular structure, which contrasts with the strong length dependence of conductance in single‐molecule junctions with the same building blocks, and the dominant charge‐transport path of molecules with two anchors transited from an intramolecular to an intermolecular path when the degree of conjugation increased. An increase in conjugation further led to higher binding probability owing to the variation in binding energies, as supported by DFT calculations. [ABSTRACT FROM AUTHOR]

Direct and label‐free detection of unmodified DNA has always been a great challenge for DNA analyses. Surface‐enhanced Raman spectroscopy (SERS) can provide structural fingerprinting of analytes with single‐molecules sensitivity, so it could be the best candidate for label‐free detection of DNA. Wild mushrooms, a very nutritious and delicious food in our lives, are widely distributed in Yunnan province. Herein, a simple and reliable method, based on SERS, was developed for label‐free detection of DNA from six wild mushrooms and three common edible mushrooms. Concentrated Ag colloid prepared by microwave heating method with high SERS activity was used to obtain high reproducible SERS spectra. SERS signatures and spectroscopic band assignments of these mushrooms DNA were analyzed. Principal component analysis was used to distinguish these nine mushrooms. This experiment provides a simple and reliable method to detect mushrooms DNA, which is useful for the study of mushrooms DNA. Also, this approach has great potential for species identification of wild mushrooms and provides a basis for learning the interaction between DNA and small molecules. To our best knowledge, it is the first SERS study on DNA from wild mushrooms. [ABSTRACT FROM AUTHOR]

Development of high‐performance organic thermoelectric (TE) materials is of vital importance for flexible power generation and solid‐cooling applications. Demonstrated here is the significant enhancement in TE performance of selenium‐substituted diketopyrrolopyrrole (DPP) derivatives. Along with strong intermolecular interactions and high Hall mobilities of 1.0–2.3 cm2 V−1 s−1 in doping‐states for polymers, PDPPSe‐12 exhibits a maximum power factor and ZT of up to 364 μW m−1 K−2 and 0.25, respectively. The performance is more than twice that of the sulfur‐based DPP derivative and represents the highest value for p‐type organic thermoelectric materials based on high‐mobility polymers. These results reveal that selenium substitution can serve as a powerful strategy towards rationally designed thermoelectric polymers with state‐of‐the‐art performances. [ABSTRACT FROM AUTHOR]

Conjugated molecules with low lying LUMO levels are demanding for the development of air stable n‐type organic semiconductors. In this paper, we report a new A‐D‐A′‐D‐A conjugated molecule (DAPDCV) entailing diazapentalene (DAP) and dicyanovinylene groups as electron accepting units. Both theoretical and electrochemical studies manifest that the incorporation of DAP unit in the conjugated molecule can effectively lower the LUMO energy level. Accordingly, thin film of DAPDCV shows n‐type semiconducting behavior with electron mobility up to 0.16 cm2⋅V−1⋅s−1 after thermal annealing under N2 atmosphere. Moreover, thin film of DAPDCV also shows stable n‐type transporting property in air with mobility reaching 0.078 cm2⋅V−1⋅s−1. [ABSTRACT FROM AUTHOR]

Photoresponsive molecular systems are essential for molecular optoelectronic devices, but most molecular building blocks are non‐photoresponsive. Employed here is a photoinduced proton transfer (PIPT) strategy to control charge transport through single‐molecule azulene junctions with visible light under ambient conditions, which leads to a reversible and controllable photoresponsive molecular device based on non‐photoresponsive molecules and a photoacid. Also demonstrated is the application of PIPT in two single‐molecule AND gate and OR gate devices with electrical signal as outputs. Out of the blue: By using a photoinduced proton‐transfer (PIPT) strategy, a non‐photoresponsive 1,3‐azulene derivative can be modulated in single‐molecule junctions by blue light, with conductance variation by almost one order of magnitude. This behavior can lead to potential applications in single‐molecule logic gate devices with electrical outputs. [ABSTRACT FROM AUTHOR]

Photooxidation under sunlight has potential in organic synthesis, bacterial killing, and organic waste treatment. Photosensitizers (PSs) can play an important role in this process. High 1O2 generation efficiency and excellent photostability under sunlight, as well as easy recyclability are ideal properties for PSs, but are not easy to achieve simultaneously. Herein, a pure organic porous conjugated polymer PS, CPTF, shows great photostability, large specific surface area, and high 1O2 generation efficiency under sunlight for photooxidation. For the oxidation of aromatic aldehyde to aromatic acid, the PS catalyst shows excellent recyclability, and enables solvent‐free reactions in high yields both under direct sunlight and simulated AM 1.5G irradiation. In addition, the successful application of CPTF as an antibacterial agent and organic waste decomposition under simulated AM 1.5G irradiation indicates the potential of CPTF in sunlight‐induced waste water treatment. A sunny outlook: A cross‐linked porous conjugated polymer photosensitizer CPTF is used for sunlight‐induced photooxidation. Under simulated AM 1.5G irradiation, benzaldehyde can be oxidized to benzoic acid easily on a 10 g scale in the presence of CPTF. In addition, CPTF can also be used as photocatalyst for sunlight‐induced organic waste decomposition and an antibacterial agent in water. [ABSTRACT FROM AUTHOR]

Frontispiece: Diazulenorubicene as a Non-benzenoid Isomer of peri-Tetracene with Two Sets of 5/7/5 Membered Rings Showing Good Semiconducting Properties Keywords: Annulation; Aromaticity; Fused Ring Systems; Semiconducting Properties; on-Surface Synthesis EN Annulation Aromaticity Fused Ring Systems Semiconducting Properties on-Surface Synthesis 1 1 1 09/20/23 20230925 NES 230925 B Organic Semiconductors b . In their Research Article (e202304632), Xi-Sha Zhang, Deqing Zhang et al. report a (3+2) annulation reaction to synthesize diazulenorubicenes showing semiconducting properties. [Extracted from the article]

A series of novel propylene‐tethered heteronuclear bis‐isatin derivatives were designed, synthesized, and assessed for their in vitro and anti‐mycobacterial activities. All hybrids exhibited considerable antibacterial and anti‐mycobacterial activities against Mycobacterium tuberculosis H37Rv and multi‐drug‐resistant tuberculosis (MDR‐TB) with minimum inhibitory concentration (MIC) ranging from 16 to 256 μg/mL. In particular, the heteronuclear bis‐isatin 4i (MIC: 25 and 16 μg/mL) was most active against M. tuberculosis H37Rv and MDR‐TB strains, which was fourfold and greater than eightfold more potent than the first‐line anti‐tubercular agents rifampicin (MIC: 64 μg/mL) and isoniazid (MIC: >128 μg/mL) against MDR‐TB, could act as a lead for further optimization. [ABSTRACT FROM AUTHOR]

Abstract: Ammonia/amine gas sensors have received increasing attention in recent years, due to their applications in monitoring of meat and seafood spoilage and air pollution as well as diagnosis of chronic diseases. Herein, a new conjugated polymer PTTEH is developed, which is composed of thieno[3,4‐b]thiophene units, with very low bandgap. The low bandgap and the existence of radical state endow the polymer thin film with good electrical conductivity. As a result, PTTEH is successfully utilized for construction of a field‐effect transistor (FET) sensor for ammonia and amines at low driving voltages, which are advantageous for practical applications. Moreover, this FET sensor shows good selectivity and high sensitivity (down to 10 ppb) toward ammonia and amines. Accordingly, the real‐time monitoring of meat spoilage is achieved with this FET sensor. These studies will open a new venue to fabricate sensitive, portable, and small size sensors for real‐time monitoring of chemical vapors. [ABSTRACT FROM AUTHOR]

In this Review, the configuration-dependent molecular recognition, aggregation-induced emission and bioactivities of I cis i / I trans i tetraphenylethene-based isomers are summarized. Aggregation-induced emission, fluorescence, molecular recognition, stereoisomers, tetraphenylethene Keywords: aggregation-induced emission; fluorescence; molecular recognition; stereoisomers; tetraphenylethene EN aggregation-induced emission fluorescence molecular recognition stereoisomers tetraphenylethene 1 1 1 05/30/23 20230526 NES 230526 Tetraphenylethene derivatives with adjustable molecular geometry emerge as an attractive paradigm for the development of smart and versatile chemical probes. [Extracted from the article]

The rational design of multifunctional materials with both emissive and semiconducting properties remains a challenge. A multifunctional cruciform donor-acceptor (D-A) molecule, 2,2′-(((4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl)bis(thiophene-5,2-diyl))bis(methanylylidene))dimalononitrile ( BDTTM), which contains a benzodithiophene as the central core, has been synthesized and, based on the output and transfer characteristics of the corresponding FETs, thin films of BDTTM exhibited ambipolar semiconducting behavior. Notably, FETs with thin films of BDTTM showed a photoresponse in both p- and n-channels, and drain-source-current enhancement under white-light irradiation could be detected, even at a low light intensity of 0.1 mW cm−2. Furthermore, BDTTM exhibited red-light emission both in solution and as a crystalline solid. A microplate of BDTTM with red-light emission displayed typical optical waveguiding behavior. [ABSTRACT FROM AUTHOR]

Singlet fission (SF), in which one singlet exciton (S1) splits into two triplets (T1) on adjacent molecules through a correlated triplet-pair 1(TT) state, requires precise but difficult tuning of exciton energetics and intermolecular electronic couplings in the solid state. Antiaromatic 4nπ dibenzopentalenes (DPs) are demonstrated as a new class of single-chromophore-based intramolecular SF materials that exhibit an optically allowed S2 state with E(S2)>2×E(T1) and an optically forbidden S1 state. Ultrafast population transfer from a high-lying S2 state to a 1(TT) state was observed in monomeric solution of styryl-substituted DP (SDP) on a sub-picosecond timescale. There is evidence of exciton diffusion (ED) of the 1(TT) state to yield two individual long-lived triplets in SDP thin film. The overall triplet yield via intramolecular SF and subsequent triplet-pair diffusion can be as high as 142±10 % in thin film. [ABSTRACT FROM AUTHOR]

Apart from sensing and imaging, luminogens with aggregation-induced emission (AIE) are also interesting for photosensitizing. The photosensitizing behavior and bacteria-killing performance of a pyridinium-substituted tetraphenylethylene with an alkyne group ( TPE-A-Py+) is reported herein. Interestingly, TPE-A-Py+ exhibits higher photosensitizing efficiency than TPE-Py+ (without alkyne group) when I− was used as a counteranion. This is well explained by the fact that the Δ ΕST between the excited singlet state ( S1) and triplet state ( T1) was lower for TPE-A-Py+ than for TPE-Py+, according to theoretical calculations. Moreover, replacement of I− with other anions (PF6−, N(SO2CF3)2− and BPh4−) led to a decrease of photosensitizing efficiency for TPE-A-Py+. Notably, TPE-A-Py+ could be used as an efficient photosensitizer to photo-inactivate ampicillin-resistant (ampr) E. coli at low concentration under white-light irradiation very quickly. [ABSTRACT FROM AUTHOR]

The fluorescence detection of nitroreductase (NTR) and evaluation of the hypoxia status of tumor cells are vital, not only for clinical diagnoses and therapy, but also for biomedical research. Herein, we report the synthesis and application of a new fluorometric 'turn-on' probe for the detection of NTR ( TPE−NO2) that takes advantage of the aggregation-induced emission of tetraphenylethylene. TPE−NO2 can detect NTR at concentrations as low as 5 ng mL−1 in aqueous solution. The detection mechanism relied on the aggregation and deaggregation of tetraphenylethylene molecules. Moreover, this fluorescent probe can be used to monitor the hypoxia status of tumor cells through the detection of endogenous NTR. [ABSTRACT FROM AUTHOR]

A comprehensive investigation into the spectral properties and excitation energy transfer in di- or tribranched dithienyldiketopyrrolopyrrole (DPP) molecules with meta-substituted benzene as a central core ( TADPP2-TT and TADPP3), by means of steady-state and transient measurements and quantum chemical calculations, is reported. Excitation in the meta-substituted chromophores is localized on one of the DPP units in the branching molecules owing to the disruption of conjugation by meta substitution for both TADPP2-TT and TADPP3. Weak electronic couplings result from the long distance between the DPP chromophores and the steric effects from the attached side chains on DPP. The attachment of the acetylene linker in each branch, which has a very low twisting barrier, could also play an important role in reducing the interaction between DPP chromophores. The dynamics of the excited states show that excitation energy transfer occurs on the picosecond scale, which is attributed to the incoherent hopping mechanism. [ABSTRACT FROM AUTHOR]