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Abstract This work aims to address the heat accumulation issue in electronic components during high‐frequency operation through the preparation of novel thermally conductive composites. First, polydopamine (PDA) and in‐situ growth of silver (Ag) nanoparticles are applied for the surface modification of graphene oxide (GO) and carbon nanotube (CNT) to prepare pGO@Ag and pCNT@Ag hybrid filler, respectively. Then, nitrile butadiene rubber (NBR) is chosen as the polymeric matrix and simultaneously incorporated with both pGO@Ag and pCNT@Ag to prepare polymeric composites with excellent thermal conductivity (TC) and dielectric constant (ɛr). Due to the construction of 3D heat conduction networks by utilizing 2D pGO@Ag and 1D pCNT@Ag, the fabricated NBR composites achieved the maximum TC of 1.0112 W/(mK), which is 636% higher than that of neat NBR (0.1373 W (mK)−1). At the filler loading of 9 vol%, the TC of pGO@Ag/pCNT@Ag/NBR composite is 152% that of GO/CNT/NBR composite (0.6660 W (mK)−1). Moreover, due to electron polarization effect of GO and CNT and micro‐capacitor effect of Ag nanoparticles, a large ɛr of 147.12 is attained at 10 Hz for NBR composites. Overall, the development of dielectric polymer materials with high TC is beneficial for enhancing the service life and safety stability of the electronic components.

Fibrin, the prominent extracellular matrix in early wound tissue, is discussed to influence immune cells and healing. The nature of fibrinogen/fibrin to form fibrillary networks is frequently exploited to engineer microenvironments for cellular analysis. This study focuses on revealing the correlation of fibril formation kinetic and the resulting network microstructure of engineered 3D fibrin networks. Different concentrations of fibrinogen (1-3 mg mL -1 ), thrombin (0.01-0.15 U mL -1 ), sodium chloride (40-120 mm), and calcium chloride (1-10 mm) are applied to assess the impact on the fibril growth kinetics by turbidity analysis and on the resulting fibril and pore diameter by laser scanning microscopy. The results highlight a direct influence of the sodium chloride concentration on fibrillation kinetics and reveal a strong correlation between fibrillation kinetics and network microstructure. With the assumption of a first-order growth kinetic, an increase of the growth constant k (0.015-0.04 min -1 ) is found to correlate to a decrease in fibril diameter (1-0.65 µm) and pore diameter (11-5 µm). The new findings enable an easy prediction of 3D fibrin network microstructure by the fibril formation kinetic and contribute to an improved engineering of defined scaffolds for tissue engineering and cell culture applications., (© 2022 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.)

Here an all-carbon linked 3D covalent organic framework (COF) is introduced by employing a templated surface reaction in a continuous flow (TSRCF). The presented method of synthesis provides spatial control over the reaction chemistry and allows for the creation of ultrasmooth COF films of desired thickness and significant crystallinity. The films show high electrical conductivity (≈3.4 S m -1 ) after being doped with tetracyanoquinodimethane (TCNQ), setting a new record for 3D COF materials. The concurrence of 3D nanosized channels and high conductivity opens up for a number of hitherto unexplored applications for this class of materials, such as high surface area electrodes, electrochemical transistors, and for electronic sensing., (© 2021 The Authors. Small published by Wiley-VCH GmbH.)

To elevate the performance of polymer solar cells (PSC) processed by non-halogenated solvents, a dissymmetric fused-ring acceptor BTIC-2Cl-γCF 3 with chlorine and trifluoromethyl end groups has been designed and synthesized. X-ray crystallographic data suggests that BTIC-2Cl-γCF 3 has a 3D network packing structure as a result of H- and J-aggregations between adjacent molecules, which will strengthen its charge transport as an acceptor material. When PBDB-TF was used as a donor, the toluene-processed binary device realized a high power conversion efficiency (PCE) of 16.31 %, which improved to 17.12 % when PC71ThBM was added as the third component. Its efficiency of over 17 % is currently the highest among polymer solar cells processed by non-halogenated solvents. Compared to its symmetric counterparts BTIC-4Cl and BTIC-CF 3 -γ, the dissymmetric BTIC-2Cl-γCF 3 integrates their merits, and has optimized the molecular aggregations with excellent storage and photo-stability, and also extending the maximum absorption peak in film to 852 nm. The devices exhibit good transparency indicating a potential utilization in semi-transparent building integrated photovoltaics (ST-BIPV)., (© 2020 Wiley-VCH GmbH.)

Assembling different kinds of 2D nanosheets into heterostructures presents a promising way of designing novel artificial materials with new and improved functionalities by combining the unique properties of each component. In the past few years, black phosphorus nanosheets (BPNSs) have been recognized as a highly feasible 2D material with outstanding electronic properties, a tunable bandgap, and strong in-plane anisotropy, highlighting their suitability as a material for constructing heterostructures. In this study, recent progress in the construction of BPNS-based heterostructures ranging from 2D hybrid structures to 3D networks is discussed, emphasizing the different types of interactions (covalent or noncovalent) between individual layers. The preparation methods, optical and electronic properties, and various applications of these heterostructures-including electronic and optoelectronic devices, energy storage devices, photocatalysis and electrocatalysis, and biological applications-are discussed. Finally, critical challenges and prospective research aspects in BPNS-based heterostructures are also highlighted., (© 2020 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

The first three-dimensional (3D) conductive single-ion magnet (SIM), (TTF) 2 [Co(pdms) 2 ] (TTF=tetrathiafulvalene and H 2 pdms=1,2-bis(methanesulfonamido)benzene), was electrochemically synthesised and investigated structurally, physically, and theoretically. The similar oxidation potentials of neutral TTF and the molecular precursor [HNEt 3 ] 2 [M(pdms) 2 ] (M=Co, Zn) allow for multiple charge transfers (CTs) between the SIM donor [M(pdms) 2 ] n- and the TTF .+ acceptor, as well as an intradonor CT from the pdms ligand to Co ion upon electrocrystallisation. Usually TTF functions as a donor, whereas in our system TTF is both a donor and an accepter because of the similar oxidation potentials. Furthermore, the [M(pdms) 2 ] n- donor and TTF .+ acceptor are not segregated but strongly interact with each other, contrary to reported layered donor-acceptor electrical conductors. The strong intermolecular and intramolecular interactions, combined with CT, allow for relatively high electrical conductivity even down to very low temperatures. Furthermore, SIM behaviour with slow magnetic relaxation and opening of hysteresis loops was observed. (TTF) 2 [Co(pdms) 2 ] (2-Co) is an excellent building block for preparing new conductive SIMs., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Easy and high efficient methods are in great demand to obtain polyimide (PI) composites with high thermal conductivity in the electronic packaging field. In this work, PI/boron nitride (BN) composites with high thermal conductivity are easily fabricated. Tightly connected and well-arranged BN platelets construct effective 3D thermally conductive networks in the PI matrix upon hot pressing, after BN platelets are coated on the surface of PI granules by the help of a kind of PI adhesive. The thermal conductivity of the PI/BN composites reaches as high as 4.47 W mK -1 at a low BN loading of 20 vol%, showing an enhancement of 2099%, compared to pure PI. Such enhancement of the thermal conductivity is the highest compared with the results in the open literature. Our work is a good example that utilized the sufficient physical connection (aggregates) of thermally conductive fillers to significantly promote the thermal conductivity of polymer composites., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this study, we report a photoanode consisting of a polymeric/inorganic nanojunction between novel nanostructured 3D C 3 N 4 nano-networks and BiVO 4 substrate. This nanojunction is formed such that 3D C 3 N 4 nano-networks with a positively charged surface are efficiently anchored on the BiVO 4 photoanode with a negatively charged surface. This electrostatic self-assembly can initiate and contribute to an intimate contact at the interfaces, leading to an enhanced photoelectrochemical activity and stability compared with that fabricated by non-electrostatic assembly. The C 3 N 4 nano-network/BiVO 4 photoanode achieved a remarkable photocurrent density of 4.87 mA cm -2 for water oxidation at 1.23 V (vs. reversible hydrogen electrode) after depositing FeOOH/NiOOH as oxygen-evolution co-catalyst, which is among the highest photocurrent densities reported so far for BiVO 4 -based photoanodes., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of amorphous 3D Co-based phosphate networks with hierarchical porosity, including the CoPi, the binary CoM 1 Pi and the trinary CoM 1 M 2 Pi (M i  = Ni II , Fe III , Ce III ) are produced via a novel bitemplate coprecipitation approach at room temperature. Interestingly, the integration of Fe III and Co II in the same network is found to significantly influence both the porosity and the electronic state of Co II . The CoFePi with a Fe III to Co II mole ratio of 0.91 has a specific surface area of 170 m 2 g -1 and average pore size of 12.3 nm, larger than those of the CoPi network; furthermore, the Co II within such CoFePi exhibits a higher oxidation state than that in the CoPi. Due to such structural and compositional merits, the binary CoFePi network shows superior oxygen evolution reaction (OER) electrocatalytic activity, which gives an overpotential as low as 0.315 V at 10 mA cm -2 and a Tafel slope of 33 mV dec -1 in 0.10 m KOH. Additionally, the trinary CoFeNiPi demonstrates similar OER catalytic performance. The two phosphate networks also exhibit remarkable catalytic stability. In view of their easy preparation, superior activity, high stability, and low cost, such transition metal phosphate networks are promising catalysts for practical OER processes., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Three Sonogashira-Hagihara polymerization protocols were applied for the synthesis of conjugated microporous polymers (CMPs) by using group IV tetra(p-ethynylphenyl) monomers with 1,4-diiodobenzene or 1,4-dibromobenzene. The optical properties and surface areas of the CMPs were compared and related to the preparation conditions and the geometry of the tetrahedral building block as obtained after X-ray analysis. In each series, surface areas decreased-independently from the chosen parameters of catalyst, base, and solvent-from carbon-centered CMPs (1595 m 2  g -1 ) to silicon-, germanium-, and tin-centered (649 m 2  g -1 ) networks., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The present communication reports a concept battery made by direct contact of magnesium foil with ultralight polyaniline (PANI) foam in the absence of additional electrolyte. Electrical current is allowed to be steadily released from the junction with a specific energy of 646 mWh g(-1) and specific capacity of 1247 mAh g(-1). Additionally, the battery offers an environmentally friendly route of hydrogen production along with discharging. Mechanistic studies indicated that the ubiquitous galvanic corrosion combined with decomposition of adsorbed trace water in the semi-conducting polymer foam enabled the generation of electricity, which overturns the traditional view. The higher moisture level is conducive to the discharge. This work is believed to open up new possibilities for the design of electrochemical batteries., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)