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The development of semiconducting polymers with good processability in green solvents and competitive electrical performance is essential for realizing sustainable large‐scale manufacturing and commercialization of organic electronics. A major obstacle is the processability‐performance dichotomy that is dictated by the lack of ideal building blocks with balanced polarity, solubility, electronic structures, and molecular conformation. Herein, through the integration of donor, quinoid and acceptor units, an unprecedented building block, namely TQBT, is introduced for constructing a serial of conjugated polymers. The TQBT, distinct in non‐symmetric structure and high dipole moment, imparts enhanced solubility in anisole—a green solvent—to the polymer TQBT‐T. Furthermore, PTQBT‐T possess a highly rigid and planar backbone owing to the nearly coplanar geometry and quinoidal nature of TQBT, resulting in strong aggregation in solution and localized aggregates in film. Remarkably, PTQBT‐T films spuncast from anisole exhibit a hole mobility of 2.30 cm2 V‐1 s‐1, which is record high for green solvent‐processable semiconducting polymers via spin‐coating, together with commendable operational and storage stability. The hybrid building block emerges as a pioneering electroactive unit, shedding light on future design strategies in high‐performance semiconducting polymers compatible with green processing and marking a significant stride towards ecofriendly organic electronics. [ABSTRACT FROM AUTHOR]

Covalent triazine frameworks (CTFs) and their derivative N‐doped carbons have attracted much attention for application in energy conversion and storage. However, previous studies have mainly focused on developing new building blocks and optimizing synthetic conditions. The use of isometric building blocks to control the porous structure and to fundamentally understand structure–property relationships have rarely been reported. In this work, two isometric building blocks are used to produce isometric CTFs with controllable pore geometries. The as‐prepared CTF with nonplanar hexagonal rings demonstrates higher surface area, larger pore volume, and richer N content than the planar CTF. After pyrolysis, nonplanar porous CTF‐derived N‐doped carbons exhibit admirable catalytic activity for oxygen reduction in alkaline media (half‐wave potential: 0.86 V; Tafel slope: 65 mV dec−1), owing to their larger pore volume and the abundance of pyridinic and graphitic N species. When assembled into a zinc–air battery, the as‐made electrocatalysts show high capacities of up to 651 mAh g−1 and excellent durability. [ABSTRACT FROM AUTHOR]

The 2D conjugated coordination polymer frameworks (2D c‐CPFs), as a novel class of electronic materials, show significant potential in modern electronic devices. However, the lack of available construction monomers greatly hinders the development as well as the fundamental electronic process understanding of 2D c‐CPF in modern electronics. Herein, a novel conjugated coordination polymer framework is developed through coordination of a new planar ligand with copper ions. Benefiting from the in‐plane d–π conjugation and out‐of‐plane π stacking, as‐made coordination polymer framework exhibits a narrow bandgap of 1.12 eV. Then, a free‐standing hybrid layered film of coordination frameworks together with exfoliated graphene is prepared as the electrode for micro‐supercapacitors. The micro‐device displays the high areal specific capacitance of 14.3 mF cm−2, outperforming most of the reported conductive polymer‐based micro‐supercapacitors. Notably, the as‐prepared micro‐supercapacitor exhibits good electrochemical stability after 5000 cycles, as well as excellent flexibility for polyethylene terephthalate‐supported devices. Herein, not only is a novel d–π conjugated coordination polymer with narrow bandgap developed, but also its application in miniature and flexible devices is identified. [ABSTRACT FROM AUTHOR]

The robust fully conjugated covalent organic frameworks (COFs) are emerging as a novel type of semi‐conductive COFs for optoelectronic and energy devices due to their controllable architectures and easily tunable the highest occupied molecular orbital (HOMO) and the lowest occupied molecular orbital (LUMO) levels. However, the carrier mobility of such materials is still beyond requirements due to limited π‐conjugation. In this study, a series of new polyarylether‐based COFs are rationally synthesized via a direct reaction between hexadecafluorophthalocyanine (electron acceptor) and octahydroxyphthalocyanine (electron donor). These COFs have typical crystalline layered structures, narrow band gaps as low as ≈0.65 eV and ultra‐low resistance (1.31 × 10−6 S cm−1). Such COFs can be composed of two different metal‐sites and contribute improved carrier mobility via layer‐altered staking mode according to density functional theory calculation. Due to the narrow pore size of 1.4 nm and promising conductivity, such COFs and electrochemically exfoliated graphene based free‐standing films are fabricated for in‐plane micro‐supercapacitors, which demonstrate excellent volumetric capacitances (28.1 F cm−3) and excellent stability of 10 000 charge–discharge cycling in acidic electrolyte. This study provides a new approach toward dioxin‐linked COFs with donor‐acceptor structure and easily tunable energy levels for versatile energy storage and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Two frontier crystalline porous framework materials, namely, metal‐organic frameworks (MOFs) and covalent organic frameworks (COFs), have been widely explored owing to their outstanding physicochemical properties. While each type of framework has its own intrinsic advantages and shortcomings for specific applications, combining the complementary properties of the two materials allows the engineering of new classes of hybrid porous crystalline materials with properties superior to the individual components. Since the first report of MOF/COF hybrid in 2016, it has rapidly evolved as a novel platform for diverse applications. The state‐of‐art advances in the various synthetic approaches of MOF/COF hybrids are hereby summarized, together with their applications in different areas. Perspectives on the main challenges and future opportunities are also offered in order to inspire a multidisciplinary effort toward the further development of chemically diverse, multi‐functional hybrid porous crystalline materials. [ABSTRACT FROM AUTHOR]

2D porous polymers with a planar architecture and high specific surface area have significant applications potential, such as for photocatalysis, electrochemical catalysis, gas storage and separation, and sensing. Such 2D porous polymers have generally been classified as 2D metal–organic frameworks, 2D covalent organic frameworks, graphitic carbon nitride, graphdiyne, and sandwich‐like porous polymer nanosheets. Among these, 2D porous polymers with sp2‐hybridized carbon (Csp2) bonding are an emerging field of interest. Compared with 2D porous polymers linked by BO, CN, or CC bonds, Csp2‐linked 2D porous polymers exhibit extended electron delocalization resulting in unique optical/electrical properties, as well as high chemical/photostability and tunable electrochemical performance. Furthermore, such 2D porous polymers are one of the best precursors for the fabrication of 2D porous carbon materials and carbon skeletons with atomically dispersed transition‐metal active sites. Herein, rational synthetic approaches for 2D porous polymers with Csp2 bonding are summarized. Their current practical photoelectric applications, including for gas separation, luminescent sensing and imaging, electrodes for batteries and supercapacitors, and photocatalysis are also discussed. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) porous carbon nanosheets (2DPCs) have attracted great attention for their good porosity and long‐distance conductivity. Factors such as templates, precursors, and carbonization–activation methods, directly determine their performance. However, rational design and preparation of porous carbon materials with controlled 2D morphology and heteroatom dopants remains a challenge. Therefore, an ionic polyimide with both sp2‐ and sp3‐hybridized nitrogen atoms was prepared as a precursor for fabricating N‐doped hexagonal porous carbon nanosheets through a hard‐template approach. Because of the large surface area and efficient charge‐mass transport, the resulting activated 2D porous carbon nanosheets (2DPCs‐a) displayed promising electrocatalytic properties for oxygen reduction reaction (ORR) in alkaline and acidic media, such as ultralow half‐wave potential (0.83 vs. 0.84 V of Pt/C) and superior limiting current density (5.42 vs. 5.14 mA cm−2 of Pt/C). As air cathodes in Zn–air batteries, the as‐developed 2DPCs‐a exhibited long stability and high capacity (up to 614 mA h g−1), which are both higher than those of commercial Pt/C. This work provides a convenient method for controllable and scalable 2DPCs fabrication as well as new opportunities to develop high‐efficiency electrocatalysts for ORR and Zn–air batteries. [ABSTRACT FROM AUTHOR]

A gas‐phase approach to form Zn coordination sites on metal–organic frameworks (MOFs) by vapor‐phase infiltration (VPI) was developed. Compared to Zn sites synthesized by the solution‐phase method, VPI samples revealed approximately 2.8 % internal strain. Faradaic efficiency towards conversion of CO2 to CO was enhanced by up to a factor of four, and the initial potential was positively shifted by 200–300 mV. Using element‐specific X‐ray absorption spectroscopy, the local coordination environment of the Zn center was determined to have square‐pyramidal geometry with four Zn−N bonds in the equatorial plane and one Zn‐OH2 bond in the axial plane. The fine‐tuned internal strain was further supported by monitoring changes in XRD and UV/Visible absorption spectra across a range of infiltration cycles. The ability to use internal strain to increase catalytic activity of MOFs suggests that applying this strategy will enhance intrinsic catalytic capabilities of a variety of porous materials. [ABSTRACT FROM AUTHOR]

Fluid in interstitial spaces accounts for ~20% of an adult body weight and flows diffusively for a short range. Does it circulate around the body like vascular circulations? This bold conjecture has been debated for decades. As a conventional physiological concept, interstitial space is a micron‐sized space between cells and vasculature. Fluid in interstitial spaces is thought to be entrapped within interstitial matrix. However, our serial data have further defined a second space in interstitium that is a nanosized interfacial transport zone on a solid surface. Within this fine space, fluid along a solid fibre can be transported under a driving power and identically, interstitial fluid transport can be visualized by tracking the oriented fibres. Since 2006, our data from volunteers and cadavers have revealed a long‐distance extravascular pathway for interstitial fluid flow, comprising at least four types of anatomic distributions. The framework of each extravascular pathway contains the longitudinally assembled and oriented fibres, working as a fibrorail for fluid flow. Interestingly, our data showed that the movement of fluid in a fibrous pathway is in response to a dynamic driving source and named as dynamotaxis. By analysis of previous studies and our experimental results, a hypothesis of interstitial fluid circulatory system is proposed. [ABSTRACT FROM AUTHOR]

Objective: Interstitial fluid in extracellular matrices may not be totally fixed but partially flow through long‐distance oriented fibrous connective tissues via physical mechanisms. We hypothesized there is a long‐distance interstitial fluid transport network beyond vascular circulations. Materials and methods: We first used 20 volunteers to determine hypodermic entrant points to visualize long‐distance extravascular pathway by MRI. We then investigated the extravascular pathways initiating from the point of thumb in cadavers by chest compressor. The distributions and structures of long‐distance pathways from extremity ending to associated visceral structures were identified. Results: Using fluorescent tracer, the pathways from right thumb to right atrium wall near chest were visualized in seven of 10 subjects. The cutaneous pathways were found in dermic, hypodermic and fascial tissues of hand and forearm. The perivascular pathways were along the veins of arm, axillary sheath, superior vena cava and into the superficial tissues on right atrium. Histological and micro‐CT data showed these pathways were neither blood nor lymphatic vessels but long‐distance oriented fibrous matrices, which contained the longitudinally assembled micro‐scale fibres consistently from thumb to superficial tissues on right atrium. Conclusions: These data revealed the structural framework of the fibrous extracellular matrices in oriented fibrous connective tissues was of the long‐distance assembled fibres throughout human body. Along fibres, interstitial fluid can systemically transport by certain driving‐transfer mechanisms beyond vascular circulations. [ABSTRACT FROM AUTHOR]

On-chip micro-supercapacitors (MSCs) are important Si-compatible power-source backups for miniaturized electronics. Despite their tremendous advantages, current on-chip MSCs require harsh processing conditions and typically perform like resistors when filtering ripples from alternating current (AC). Herein, we demonstrated a facile layer-by-layer method towards on-chip MSCs based on an azulene-bridged coordination polymer framework (PiCBA). Owing to the good carrier mobility (5×10−3 cm2 V−1 s−1) of PiCBA, the permanent dipole moment of azulene skeleton, and ultralow band gap of PiCBA, the fabricated MSCs delivered high specific capacitances of up to 34.1 F cm−3 at 50 mV s−1 and a high volumetric power density of 1323 W cm−3. Most importantly, such MCSs exhibited AC line-filtering performance (−73° at 120 Hz) with a short resistance-capacitance constant of circa 0.83 ms. [ABSTRACT FROM AUTHOR]

On-chip micro-supercapacitors (MSCs) are important Si-compatible power-source backups for miniaturized electronics. Despite their tremendous advantages, current on-chip MSCs require harsh processing conditions and typically perform like resistors when filtering ripples from alternating current (AC). Herein, we demonstrated a facile layer-by-layer method towards on-chip MSCs based on an azulene-bridged coordination polymer framework (PiCBA). Owing to the good carrier mobility (5×10−3 cm2 V−1 s−1) of PiCBA, the permanent dipole moment of azulene skeleton, and ultralow band gap of PiCBA, the fabricated MSCs delivered high specific capacitances of up to 34.1 F cm−3 at 50 mV s−1 and a high volumetric power density of 1323 W cm−3. Most importantly, such MCSs exhibited AC line-filtering performance (−73° at 120 Hz) with a short resistance-capacitance constant of circa 0.83 ms. [ABSTRACT FROM AUTHOR]

A novel lyotropic liquid-crystal (LC) based assembly strategy is developed for the first time, to fabricate composite films of vanadium pentoxide (V2O5) nanobelts and graphene oxide (GO) sheets, with highly oriented layered structures. It is found that similar lamellar LC phases can be simply established by V2O5 nanobelts alone or by a mixture of V2O5 nanobelts and GO nanosheets in their aqueous dispersions. More importantly, the LC phases can be retained with any proportion of V2O5 nanobelts and GO, which allows facile optimization of the ratio of each component in the resulting films. Named VrGO, composite films manifest high electrical conductivity, good mechanical stability, and excellent flexibility, which allow them to be utilized as high performance electrodes in flexible energy storage devices. As demonstrated in this work, the VrGO films containing 67 wt% V2O5 exhibit excellent capacitance of 166 F g−1 at 10 A g−1; superior to those of the previously reported composites of V2O5 and nanocarbon. Moreover, the VrGO film in flexible lithium ion batteries delivers a high capacity of 215 mAh g−1 at 0.1 A g−1; comparable to the best V2O5 based cathode materials. [ABSTRACT FROM AUTHOR]

Abstract: An unprecedented sacrificial templating strategy towards hierarchically porous N‐doped carbon nanosheets (PNC‐A) proceeds by the thermal treatment of the graphene hybrid coated with polyaniline‐encapsulated tin oxide nanoparticles, and the following etching process with acid and NH3. The resultant PNC‐A exhibits well‐defined 2D morphology, high ratio of graphitic N and pyridinic N atoms as the active sites, and hierarchically porous structures with high specific surface area. Serving as the electrocatalyst for oxygen reduction reaction (ORR) in basic media, PNC‐A exhibits excellent catalytic activity via a four‐electron pathway with half‐wave potentials of 0.76 V vs. RHE electrode in alkaline media; the diffusion‐limiting current density is 5.48 mA cm−2, which is superior to most of the reported metal‐free ORR catalysts and comparable to state‐of‐the‐art Pt/C. [ABSTRACT FROM AUTHOR]

A novel phosphorus-containing porous polymer is efficiently prepared from tris(4-vinylphenyl)phosphane by radical polymerization, and it can be easily ionized to form an ionic porous polymer after treatment with hydrogen iodide. Upon ionic exchange, transition-metal-containing anions, such as tetrathiomolybdate (MoS42-) and hexacyanoferrate (Fe(CN)63-), are successfully loaded into the framework of the porous polymer to replace the original iodide anions, resulting in a polymer framework containing complex anions (termed HT-Met, where Met = Mo or Fe). After pyrolysis under a hydrogen atmosphere, the HT-Met materials are efficiently converted at a large scale to metal-phosphidecontaining porous carbons (denoted as MetP@PC, where again Met = Mo or Fe). This approach provides a convenient pathway to the controlled preparation of metal-phosphide-loaded porous carbon composites. The MetP@PC composites exhibit superior electrocatalytic activity for the hydrogen evolution reaction (HER) under acidic conditions. In particular, MoP@PC with a low loading of 0.24 mg cm-2(on a glass carbon electrode) affords an iR -corrected (where i is current and R is resistance) current density of up to 10 mA cm-2at 51 mV versus the reversible hydrogen electrode and a very low Tafel slope of 45 mV dec-1, in rotating disk measurements under saturated N2conditions. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have been widely studied due to their versatile applications and easily tunable structures. However, heteroatom‐metal coordination dominates the MOFs community, and the rational synthesis of carbon–metal coordination‐based MOFs remains a significant challenge. Herein, two‐dimensional (2D) MOFs based on silver–carbon linkages are synthesized through the coordination between silver(I) salt and isocyanide‐based monomers at ambient condition. The as‐synthesized 2D MOFs possess well‐defined crystalline structures and a staggered AB stacking mode. Most interestingly, these 2D MOFs, without π–π stacking between layers, exhibit narrow band gaps down to 1.42 eV. As electrochemical catalysts for converting CO2 to CO, such 2D MOFs demonstrate Faradaic efficiency over 92 %. Surprisingly, the CO2 reduction catalyzed by these MOFs indicates favorable adsorption of CO2 and *COOH on the active carbon sites of the isocyanide groups rather than on silver sites. This is attributed to the critical σ donor role of isocyanides and the corresponding ligand‐to‐metal charge–transfer effect. This work not only paves the way toward a new family of MOFs based on metal–isocyanide coordination but also offers a rare platform for understanding the electrocatalysis processes on strongly polarized carbon species. [ABSTRACT FROM AUTHOR]

Cover Feature: Ionic Polyimide Derived Porous Carbon Nanosheets as High-Efficiency Oxygen Reduction Catalysts for Zn-Air Batteries (Chem. Eur. J. 29/2020) Keywords: ionic polyimides; oxygen reduction reaction; porous carbon nanosheets; Zn-air battery EN ionic polyimides oxygen reduction reaction porous carbon nanosheets Zn-air battery 6288 6288 1 05/23/20 20200520 NES 200520 B Two-dimensional porous carbon nanosheets (2DPCs) b with controlled hexagonal morphology are reported, using LDH and ionic polyimide as template and carbon precursor, respectively. Looking at the top right-hand corner, we can see the polyimide model, which represents the viologen-linked ionic polyimide with both sp SP 2 sp - and sp SP 3 sp -hybridized nitrogen atoms. [Extracted from the article]

2D soft nanomaterials are an emerging research field due to their versatile chemical structures, easily tunable properties, and broad application potential. In this study, a benzene‐bridged polypyrrole film with a large area, up to a few square centimeters, is synthesized through an interfacial polymerization approach. As‐prepared semiconductive films exhibit a bandgap of ≈2 eV and a carrier mobility of ≈1.5 cm2 V−1 s−1, inferred from time‐resolved terahertz spectroscopy. The samples are employed to fabricate in‐plane micro‐supercapacitors (MSCs) by laser scribing and exhibit an ultrahigh areal capacitance of 0.95 mF cm−2, using 1‐ethyl‐3‐methylimidazolium tetrafluoroborate ([EMIM][BF4]) as an electrolyte. Importantly, the maximum energy and power densities of the developed MSCs reach values up to 50.7 mWh cm−3 and 9.6 kW cm−3, respectively; the performance surpassing most of the 2D material‐based MSCs is reported to date. [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on characterization of aortic valve calcification at different stage of disease. Topics include relation of aortic valve calcification to arteriosclerosis and coronary heart disease; use of micro-area synchrotron radiation X-ray powder diffraction for analyzing calcification powder; observation of calcification spheres in scanning electron microscopy; and gradual increase of the spheres with progress of the disease.

In article number 1606269, Haiqing Liu, Dongqing Wu, Xinliang Feng, and co‐workers develop a lyotropic liquid crystal based assembly strategy to fabricate composite films of vanadium pentoxide nanobelts and graphene oxide sheets. The obtained composite films possess highly oriented layered structures, high electrical conductivity, good mechanical stability, and excellent flexibility, which allows their application as high performance electrodes in flexible energy storage devices. [ABSTRACT FROM AUTHOR]