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Solid-state lithium metal batteries built with composite polymer electrolytes using cubic garnets as active fillers are particularly attractive owing to their high energy density, easy manufacturing and inherent safety. However, the uncontrollable formation of intractable contaminant on garnet surface usually aggravates poor interfacial contact with polymer matrix and deteriorates Li + pathways. Here we report a rational designed intermolecular interaction in composite electrolytes that utilizing contaminants as reaction initiator to generate Li + conducting ether oligomers, which further emerge as molecular cross-linkers between inorganic fillers and polymer matrix, creating dense and homogeneous interfacial Li + immigration channels in the composite electrolytes. The delicate design results in a remarkable ionic conductivity of 1.43×10 -3 S cm -1 and an unprecedented 1000 cycles with 90% capacity retention at room temperature is achieved for the assembled solid-state batteries.

MAX-phase materials, bulk as well as film, have manifested outstanding potential applications owing to their unusual properties. Usually, MAX-phase is achieved after higher ex-situ post-annealing (≥1000 ℃) treatment. Here, we report single-step transition to Ti2AlC MAX-phase, deposited on stainless-steel(SS) by mid-frequency magnetron-sputtering system, at a lower substrate temperature of 750 ℃. The microstructure, phase and morphological characterization reveals that the compact, dense and crack-free film comprises of randomly oriented grains. Importantly, the surface of the film still remains crack-free after transition to the MAX-Phase. Moreover, a large improvement in conductivity for the film deposited at 750 ℃ (ICR = 3.27 mΩ.cm2 under 140 N. cm−2) as compared to Ti-Al-C film deposited at 500 ℃ (ICR ≥ 400 mΩ.cm2) elucidates the MAX-phase formation. The films with such low ICR values (

All-solid-state lithium metal batteries are highly attractive because of their high energy density and inherent safety. However, it is still a great challenge to design the solid electrolytes with ...

Here we present a magnetic recyclable photo-Fenton catalyst CoFe2O4@PPy with uniform morphology and excellent dispersibility prepared via simple in situ Fenton oxidization polymerization. The CoFe2O4 core provides good magnetic recyclability for the catalysts as well as the ion source for catalyzed decomposition of H2O2 in PPy coating. The optimal catalytic effect can be obtained by adjusting the ratio of CoFe2O4 and PPy. Methylene blue, Methyl orange and Rhodamine B (RhB) employed as model pollutants certificated that the catalyst exhibits a wide range of photodegradability. The decoloration rates reach nearly 100% in the photodegradation of 10 mg L−1 RhB after 2 h visible-light irradiation and only low toxicity small molecules are detected by LC-MS. Moreover, the catalytic activity remains after 5 cycles with decoloration rates up to 90%. The degradation measurement in the presence of scavengers of reactive species reveals that the positive holes (h+) and hydroxyl radical (·OH) are the main reactive oxygen species in the CoFe2O4@PPy system. The performance enhancement may be attributed to the combination of improved Fenton activity by coordinated Fe2+ and PPy redox pairs and photo-catalytic activity by broaden adsorption and photo-generated charge separation.

In this study, a multilayered van der Waals (vdW) heterostructure, HfS2/MoTe2, was modeled and simulated using density functional theory (DFT). It was found that the multilayers (up to 7 layers) are typical indirect bandgap semiconductors with an indirect band gap varying from 0.35 eV to 0.51 eV. The maximum energy value of the valence band (VBM) and the minimum energy value of the conduction band (CBM) of the heterostructure were found to be dominated by the MoTe2 layer and the HfS2 layer, respectively, characterized as type-II band alignment, leading to potential photovoltaic applications. Optical spectra analysis also revealed that the materials have strong absorption coefficients in the visible and ultraviolet regions, which can be used in the detection of visible and ultraviolet light. Under an external strain perpendicular to the layer plane, the heterostructure exhibits a general transition from semiconductor to metal at a critical interlayer-distance of 2.54 A. The carrier effective mass and optical properties of the heterostructures can also be modulated under external strain, indicating a good piezoelectric effect in the heterostructure.

Bipolar plates (BPs) are key component of a fuel cell and the high prices of fuel cell are owed to the use of expensive BPs. Metals are cheap alternate to the conventional thicker and expensive graphitic BP plates. Stainless steel (SS) is considered to be the most suitable future BP material but highly corrosive nature of metals prevents their direct use as BPs, so surface treatment is obligatory. Ti–Al–C is an important ternary metal carbide which possess various unique and useful properties and could be considered as an effective coating material for SS BPs. Since the film properties are sensitive to the substrate type, so a detailed investigation about the morphology and microstructure of Ti–Al–C films, deposited on two different substrates (SS304 and SS316) by a combined ECR-CVD and PVD system, as a function of annealing temperature is reported hereby. It was observed that change in microstructure is diverse for different substrates with annealing temperature. Moreover, the formation of Ti2AlC MAX phase along with other phases was also recognized at an annealing temperature of 700 °C. Our study provides an insight about the variation in morphology and microstructure of Ti–Al–C thin films on SS substrates with annealing temperature.

Over the past decade, intensive research efforts have been directed toward the field of organic–inorganic hybrid perovskites, with dramatic progress made in both the photovoltaic performance and device stability. Therefore, it has become the fastest growing photovoltaic research area. Perovskite materials use low-cost earth-abundant elements and can be solution-processed; furthermore, the technology is compatible with large-scale roll-to-roll manufacturing. Recently, the successful demonstration of the photovoltaic performance of perovskites reaching that of the commercialized monosilicon photovoltaic technology combined with the significantly improved stability has made scaling-up the perovskite PV technology to become a new research area, which is the topic of this review. First, the fundamental background knowledge of classical nucleation and crystal growth from a solution is summarized along with its application in perovskite film evolution. We then discuss the common perovskite PV device architectures and perovskite layer deposition methods, followed by summarizing scalable solution approaches with recent progress and related challenges for the scaling-up process. Upon the introduction of the current in-depth understanding of perovskite nucleation and crystal growth, external strategies (including both physical and chemical approaches) controlling the perovskite film formation are reviewed in diverse scalable manufacturing methods. Overall, aiming at overcoming the challenges of transferring from laboratory research, we provide an overview of achieving high-performance perovskite solar cells by using scalable fabrication methods via precise nucleation and crystal growth control during the perovskite film formation process.

A novel visible-light-driven Cu/rGO/MoS2 (CRM) ternary nanostructure as a photocatalyst with high catalytic activity towards environmental purification using solar energy was successfully synthesized through a facile solvothermal method. It was found that the nanoflower structure of MoS2 increased the number of its exposed edges. Meanwhile rGO as a catalytic substrate played a role of charge-carrier channel to improve the separation of holes and electrons, which originated from the band gap absorption of MoS2. The content of Cu in photocatalyst affected photocatalytic performance obviously. And the optimal 30% Cu/rGO/MoS2 possessed the highest photocatalytic performance, which could be attributed to the improved separation of charges and synergistic effects among Cu, rGO and MoS2. The removal efficiency of Rhodamine B (RhB) over CRM was up to 100% in 5 min. CRM as a photocatalyst maintained good reproducibility and stability during 3 times of the recycle experiments. These results indicate CRM is a promising photocatalyst for degrading organic pollutants in wastewater.

Efforts to develop microcapsules that respond to different stimuli derive from the incorporation of multiple dynamic assemblies of diverse functional species to the capsule shells. However, this usually involves complicated preparation processes that ultimately hinder the integration of multiple functionalities in a single material. This is addressed in the present work by proposing a multilevel interfacial assembly approach involving polymeric complexes that facilitate the fabrication of multistimuli-responsive microcapsules based on one-step Pickering emulsification using oppositely charged polycation-graphene oxide (GO) and polyanion-surfactant complexes prepared in immiscible liquid solutions. The complexes initially stabilize the emulsion based on electrostatic interactions. Subsequently, the highly dynamic bonding between the polymeric complexes facilitates the rearrangement of components at the oil/water interface to form a continuous interfacial shell membrane. The integrity of the microcapsule shells is sensitive to near-infrared irradiation owing to the GO component and is also sensitive to NaCl content because the assemblies between nanoparticles and polyelectrolytes are bonded through electrostatic interactions. The generality of the proposed strategy is demonstrated by the interfacial assembly of polycation-Fe3O4 complexes and polyanion-surfactant complexes. The resulting microcapsules exhibit salt responsiveness, pH responsiveness, and the ability to be positioned controllably by the application of an external magnetic field. This work provides a promising approach for the preparation of multistimuli-responsive microcapsules.

Smart materials with multiple shape memory capacities have gradually attracted the interest of a lot of researchers due to their potential application in textiles, smart actuators, and aerospace engineering. However, the design and sustainable synthesis of multiple shape memory polymers (SMPs) simultaneously possessing robust mechanical strength, reprocessability, and reconfigurability still remain full of challenges. Starting from a readily available biomass material cellulose, a well-defined SMP, cellulose-graft-poly(n-butyl acrylate-co-1-vinylimidazole) copolymer (Cell-g-(BA-co-VI)) was facilely synthesized by addition-fragmentation chain transfer polymerization (RAFT) and the subsequent metallosupramolecular cross-linking. Taking advantage of the dynamic bonding, i.e., the rapid reversible fragmentation and the formation of metal ion-imidazole coordination, polymer networks with highly tunable mechanical properties, excellent solid-state plasticity, and quadruple-shape memory capacity are handily attainable. Microscopically, the metal-ligand clusters have a strong tendency to phase segregate from the soft grafted copolymers indicated by atomic force microscopy (AFM), and these serve as netpoints to construct novel SMPs. This article represents our new exploration of the next-generation SMPs based on cellulose backbone where carrying with supramolecular cross-linked soft grafted copolymers. This architecture design allows achieving robust, reprocessable, and reconfigurable thermoplastic SMPs that are difficult to realize by many other methods. Integrating these properties into one system in a synergetic manner also provides a novel approach to the high value addition application of cellulose in the fabrication of advanced functional materials.

Flexible fiber-based supercapacitors applied in portable energy storage devices and wearable electronics have recently aroused widespread research interests. However, challenges still exist in the pursuit of facile fabrication technique for simultaneously realizing high capacitive performance and excellent mechanical stability. Here, two novel types of core-sheathed hybrid electrodes with carbon nanotube fiber (CNF) as the core and three-dimensional (3D) porous carbon nanotubes/polypyrrole (CNTs/PPy) or reduced graphene oxide (rGO) as the sheath were hierarchically constructed through one-pot electrochemical deposition. An all-solid-state asymmetric fiber-shaped supercapacitor was assembled by wrapping the gel electrolyte coated negative CNF/rGO electrode along the positive CNF/CNTs/PPy electrode. Thanks to the combination of abundant 3D pore structure and synergistic effect of different components in the fiber electrodes, the resulted supercapacitors exhibited a broadened potential window of 1.6 V, a high areal specific capacitance of 58.82 mF cm−2 and a high areal energy density of 20.91 μW h cm−2. It should be noted that 98.6% of the initial capacitance of the supercapacitor device can still be maintained after experiencing 200 reciprocating bending cycles, demonstrating outstanding mechanical stability. Moreover, the supercapacitor exhibited excellent cyclic performance, which was testified by 90% capacity retention after 10000 times of galvanostatic charge-discharge process.

The healing mechanisms and healing performance of cementitious materials are reviewed, including autogenic self-healing and bacteria-based self-healing, as well as the use of mineral admixtures, polymeric adhesive agents, superabsorbent polymers, and shape memory materials. To determine the robustness of various self-healing methods, several reliable methods for the assessment of the healing efficiency are reviewed in terms of the mechanical properties. In addition, a comprehensive review of the applicable techniques is provided, i.e., microscopy, spectroscopy, thermoanalysis, and imaging for the characterization of the healing products, the microstructure, and the healing process. To demonstrate the applicability of various self-healing methods in engineering practice, the major disadvantages and challenges of the self-healing materials and encapsulation techniques are reviewed and the future development in the field of self-healing cementitious materials is addressed. Finally, an engineering case study on the healing efficiency of cementitious materials for four self-healing systems is discussed.

The development of acid environment-applicable fluorescence sensor is challenging but attractive topic, which can achieve the rapid and comprehensive evaluation of total soluble heavy metal content in natural water. In this work, a quinoline-containing Schiff base, AMQD, was utilized as fluorescence probe for Cd2+. Interestingly, the obtained chemosensor exhibited much better fluorescence detection sensitivity and selectivity toward Cd2+ in acidic 10% methanol aqueous solution (pH 4) comparing to those in neutral environment. Initially, the fluorescence emission of AMQD was almost invisible with the absence of metal ions, while a significant turn-on fluorescence response (~425 nm) can be observed with the addition of Cd2+. The fluorescence detection possesses excellent selectivity without the interference of any other metal cation. The recognition ratio between the fluorescence sensor AMQD and Cd2+ was confirmed to be 1:1, and the detection limit was calculated to be 2.4 nM.

Next generation lithium batteries require new electrolytes with good safety, excellent ionic conductivity, high electrochemical stability and good cycling performance. Herein, we first report a solid composite polymer electrolyte comprises of Li6.4La3Zr1.4Nb0.6O12 fillers and polyethylene oxide matrix. The ionic conductivity of the solid composite electrolyte is significantly improved to 1.4 × 10−3 S cm−1 (60 °C) and the electrochemical window is enhanced to 5.2 V, respectively, by incorporation of Li6.4La3Zr1.4Nb0.6O12 powder at a weight ratio of 0.5:1 with respect to polyethylene oxide. The solid batteries employing the composite electrolytes are able to work at room temperature and have a capacity retention of 99% after cycle. The performance improvement is primarily due to the combined functions of each component in the composite: (i) the incorporation of fillers effectively decreases the crystallinity of PEO, providing more amorphous region for ion conduction; (ii) Li6.4La3Zr1.4Nb0.6O12 serves as a fast ion conductor in the composite and enhance the electrochemical stability; (iii) the polymer matrix forms intimate surface contact with fillers and electrodes, reducing the bulk and interfacial resistance. The composite polymer electrolyte in this work would be a competitive alternative for the next generation solid state lithium rechargeable batteries.

Light-diffusing materials (LDMs) are essential for diffusing indoor light-emitting diode (LED) illumination to soft light. The size and refractive index of the light-diffusing agent are the...

To obtain the mechanical parameters for a microcapsule, such as the Young's modulus, yield stress, and hardening coefficients using different mechanical constitutive models, parameter identification must be implemented using inverse analysis. In the present study, a new approach combining the finite-element method and an optimisation procedure is proposed for determining the constitutive parameters of urea-formaldehyde microcapsules, in which three types of elastic-plastic constitutive models are considered: the power-law hardening model, the elastic-perfectly plastic model, and the elastic-perfectly plastic model with linear hardening. A nonlinear optimisation procedure is applied to determine the minimum of the multivariable objective function, which is defined as the norm of the difference between the numerical and experimental results. The efficiency and robustness of the proposed method are verified with different initial values and numbers of elements. The force-displacement curves from a numerical simulation show good agreement with the experimental data, indicating that the proposed approach and the mechanical parameters determined are reliable.

As an n-type semiconductor with a band gap of 1.9–2.2 eV, α-Fe2O3 is widely applied for photo-electrodes, organic pollutant degradation, ion adsorption, gas sensors, etc. Therefore, controlled synthesis of hematite with certain morphology has attracted increasing attention due to the unique properties associated with a specific crystal face. Here, we present a simple hydrothermal method to prepare hematite mesocrystals with novel morphologies. Substituted vicinal diol and alkamine were generated via hydrolysis and aminolysis of glycidyl methacrylate and used as novel capping agents to obtain plate-like and hexagonal bipyramidal mesocrystals, respectively. The effects of capping agents on morphology were investigated and the formation mechanism was discussed. The mainly exposed faces of the plate-like and bipyramid-like mesocrystals were the {001} and {116} planes, respectively. Improvement in the catalytic activity for the photo-Fenton reaction was achieved probably due to the specific exposed crystal faces.

The demands for achieving microencapsulated phase-change materials (MEPCMs) with high thermal-energy storage ability have motivated increasing research interest in inorganic filler-modified MEPCMs. However, challenges for such MEPCMs still exist in the pursuit of good compatibility of inorganic particles with the core or shell material. Here, a novel type of octadecylamine-grafted graphene oxide (GO-ODA) -modified MEPCMs using melamine-formaldehyde (MF) resin as the shell material and the mixture of GO-ODA and n-octadecane as the core material was fabricated via in-situ polymerization. The alkylated GO with a thickness of ∼1 nm was confirmed to be highly compatible with the core material. The as-prepared MEPCMs with a regular spherical shape were dispersed without any agglomeration, and the size decreased with increasing the filling amounts of GO-ODA. The incorporation of GO-ODA promoted the crystallization of n-octadecane, resulting in an observable reduction in supercooling degree. The encapsulation efficiency of MEPCMs was calculated to be over 88.0%, and the melting/freezing latent heats reached to a level as high as 207.2 J g−1 and 202.5 J g−1, respectively, even at a tiny loading level of 0.5%. Besides, the GO-ODA incorporated MEPCMs showed a good thermal cycling stability during a phase change. Moreover, a substantial enhancement in thermal transfer rate and a less marked heating effect for the MEPCMs containing GO-ODA were observed from the thermal conductivity tests and infrared thermography analysis. The findings suggested that the prepared MEPCMs are promising for applications in the fields of thermal energy storage and temperature regulation due to their enhanced thermal transfer performance and prominent phase-change enthalpy.

Graphite-like carbon films are deposited on 304SS substrates with different duty cycles and bias voltages by unbalanced magnetron sputtering, both the alternating current (AC) twinned and direct current (DC) single graphite targets are used. The microstructures and properties are investigated as bipolar plate for proton exchange membrane fuel cell (PEMFC). It is found that the surface compactness and sp2 fraction are significantly affected by the duty cycle and bias voltage. The electrical resistivity and interface contact resistance (ICR) first decrease and then increase with increasing duty cycle, which is completely dominated by the sp2 fraction. However, although the electrical resistivity and sp3/sp2 ratio monotonously increases with increasing bias voltage, the ICR values show an initial decrease and final increase for appearing a difference between 0 V and −75 V, a mechanism of electronic channels is put forward to explain this result. The lowest ICR of carbon films reaches 8.4 mΩcm2 at a compaction force of 140 N/cm2, which is hopeful to replace commercial graphitic plate. In addition, the corrosion potential and current density are closely related to the surface morphology. The perfect duty cycle and bias voltage are 40% and −75 V respectively in this research, which promotes a most conductive, moderate corrosion resistant and well hydrophobic carbon film to form.

Titanium dioxide (TiO2) is a common photocatalyst for organic pollutants degradation. However, in practical application, the poor adsorption capacity of pure TiO2 seriously impeded its efficiency in the degradation of organic molecules. In this work, a series of hierarchical wrinkle mesoporous silica supported TiO2 nano-composite particles (TiO2 @WMS-COOH) were successfully prepared. Thanks to their high surface areas, large pore volumes and mesoporous structures, these materials showed high adsorption capacity and excellent photocatalytic performance towards dye molecules, which is comparable to or even better than commercial catalyst P25. Moreover, their photocatalytic efficiency can be further enhanced by increasing the calcination temperature during preparation process. Therefore it can be concluded that the TiO2 @WMS-COOH particles may find promising applications in the photodegradation of organic pollutants. Keywords: Hierarchical wrinkled mesoporous silica, Titanium dioxide, Photocatalytic performance, Organic pollutants

A new type of ternary carbon nanotube fiber (CNF)/three-dimensional (3D) porous carbon nanotubes (CNTs)/polyaniline (PANI) electrodes with a double core-sheathed architecture composed of CNF/CNTs and CNTs/PANI was fabricated via low-potential electrophoretic deposition of CNTs and subsequent electrochemical polymerization of PANI on the CNF surface. The resulting all-solid-state supercapacitor possesses a high specific capacitance of 67.31 mF cm−2 at the current density of 0.5 mA cm−2 and only a loss as less as 10% of its initial specific capacitance after 5000 charge-discharge cycles. Furthermore, it is capable of withstanding different bending deformations, and can maintain 99.8% capacitance, even after experiencing the bending of 180° for 500 times, which manifests a significant application potential in the field of flexible electronic devices.

Although solid composite electrolytes show tremendous potential for the practical solid-state lithium metal batteries, searching for a straightforward tactic to promote the ion conduction at electrolyte/electrode interface, especially settling lithium dendrites formation caused by the concentration gradient polarization, are still long-standing problems. Here, the authors report a corrugated 3D nanowires-bulk ceramic-nanowires (NCN) skeleton reinforced composite electrolyte with regulated interfacial Li-ion transport behavior. The special and integrated NCN skeleton endows the electrolyte with fast Li-ion transfer and solves the Li

Owing to their excellent tissue-penetration ability, near-infrared (NIR) photothermal-responsive intelligent materials show remarkable advantages in biomedical applications. However, the majority the previously reported NIR-absorbing agents are metal- and carbon-based nanoparticles, both of which possess low photothermal conversion efficiency and poor biocompatibility. Herein, polydopamine modified black phosphorus (pBP) nanosheet-containing poly(vinyl alcohol) (PVA) composite hydrogels are facilely fabricated via a freezing/thawing approach. Taking advantage of the high photothermal conversion efficiency of pBP, the prepared composite hydrogels exhibit a fascinating on-demand NIR-responsive drug release behavior. An in vitro cell culture study demonstrates that these composite hydrogels present good biocompatibility and cellular interaction. Moreover, since the incorporated pBP nanosheets can form a strong hydrogen bonding interaction within the PVA matrix, the composite hydrogels also show enhanced mechanical properties. We believe that the robust mechanical properties and excellent biocompatibility accompanied by the highly controllable NIR-responsive drug release performance of the obtained composite hydrogel augur well for its diverse future applications in the biomedical field.

Hierarchical wrinkled mesoporous silica nanoparticles (WMS NPs) bedecked with diverse functionality density of amino groups (WMSs-N2, WMSs-NN and WMSs-NNN) were first synthesized via typical Sol–Gel method, and then utilized for the in situ reduction of nanosilver with sodium borohydride. Elegantly distributed Ag NPs (ca. 7–10 nm, 3–5 nm) on WMSs-N2 and WMSs-NN without any agglomeration were obtained respectively, while Ag NPs (ca. 50 nm) dispersed on WMSs-NNN were obviously larger and slightly agglomerated. Compared to pure Ag NPs, all the obtained Ag@WMSs composites were durable and displayed much better antibacterial performance, with a minimal inhibitory concentration of 12–80 mg L−1 and a minimal bactericidal concentration of 24–108 mg L−1, respectively. Moreover, it was found that the functionality density of amino groups and the specific surface area of WMSs played a crucial role for the antibacterial performance of the obtained nanocomposites. Because WMSs-NN had higher specific surface area and surface amino density than WMSs-N2, the size and dispersion of Ag NPs on WMSs-NN were smaller and superior to those of Ag NPs on WMSs-N2, respectively. Accordingly, Ag@WMSs-NN displayed a better antibacterial capacity than Ag@WMSs-N2. As for Ag@WMSs-NNN, owing to the high loading content of Ag NPs, they exhibited the best antibacterial and bactericidal properties.

Information regarding the effect of nanoscale titanium dioxide particles (nTiO2) on the environment under dark conditions is scarce, and the effect of nTiO2 on fungi is largely unknown. Due to its huge size and high sensitivity to external stimuli, the slime mold fungi cell, Physarum polycephalum macroplasmodium, was utilized as a novel subject for the toxicity investigations in the present study, and oxidative stress from nTiO2 on the macroplasmodium was assessed under dark conditions. Short exposure (2–3 h) caused an intracellular reactive oxygen species (ROS) imbalance, and an anti-oxidative mechanism was activated from intermediate doses of nTiO2 (5–18 mg/mL). At long exposure times (~3 days), relatively low doses of nTiO2 (≤9 mg/mL) stimulated the growth of macroplasmodium and oxidative stress without DNA damage, whereas higher doses of nTiO2 (≥15 mg/mL) led to growth inhibition, significant DNA oxidative damage, and activation of the DNA single-strand repairing system. Although DNA oxidative damage was decreased to the same level as the control group by the supplementation of the anti-oxidant vitamin C, growth of the macroplasmodium failed to be completely restored. We inferred that nTiO2 induced a complicated toxicity effect on P. polycephalum in addition to DNA oxidative damage. Taken as a whole, the present study implied the probability of using P. polycephalum macroplasmodium for toxicity studies at the single-cell level, indicating that nTiO2 could induce oxidative stress or damage in P. polycephalum even under dark conditions and suggesting that the release of nTiO2 could lead to a growth imbalance of slime molds in the environment.

All-solid-state lithium metal batteries are highly attractive because of their high energy density and inherent safety. However, it is still a great challenge to design the solid electrolytes with high ionic conductivity at room temperature and good electrode/electrolyte interfacial compatibility simultaneously in a facile and scalable way. In this work, for the first time, the combination of salt affluent Poly(ethylene oxide) with Li

Here we present a magnetic recyclable photo-Fenton catalyst CoFe

In this study, a multilayered van der Waals (vdW) heterostructure, HfS

Controlled release of hydrophobic agents from salt-responsive capsules is hindered by the hydrophilic shell and interfacial tension between inner oil and surrounding water. Rupturing shells in salt solution is another effective way. However, the densely entangled polyelectrolytes (PEs) in shells determined that the rupture requires extremely high ion-strength. Herein, salt-responsive capsules with double-network shells including a continuous PE-nanocrystal network and interfacial ion pairs are proposed and revealed via a one-step interfacial multilevel and multicomponent assembly (IMMA) method. Rigid nanocrystals can weaken the entanglements of PE chains and reduce the critical salt-concentration. Interfacial ion pairs are responsible for maintaining the stability of the shells. Such double networks enable the disintegration of capsules in an applicable salt-concentration without damaging the stability of capsules. In addition, hydrophobic domains assemblied by surfactants and PE-nanocrystal network supply transport pathway for oil to across hydrophilic shells and subsequently produce inverse micelle to carry oil into water. The mechanism of formation and release of capsules is systematically investigated, which further demonstrates IMMA to be a typical method for creation of sophisticated structures in a brief way.

Ti3SiC2-phase-coating is considered as a candidate for protective coating on bipolar plates in proton exchange membrane fuel cells with good corrosion resistance and electrical conductivity. In this work, Ti–Si–C coatings are prepared on stainless steel substrates by direct current and pulse magnetron sputtering, followed by vacuum heat-treatment to generate Ti3SiC2. Our findings indicate that the Ti3SiC2 coatings exhibit an excellent contact resistance and a good anticorrosion performance with low corrosion current densities in simulated proton exchange membrane fuel cells environments. Keywords: Ti3SiC2, MAX phase, Bipolar plate, Electrical conductivity, Corrosion resistance

The inherent susceptibility to oxidation and poor sinterability significantly limit the practical application of Cu-based conductive inks. Most methodologies employed for the inks like organic polymer coatings and inorganic metal deposition are generally ineffective. Herein, we report the design of a novel hierarchical Cu architecture to simultaneously improve the antioxidative and sinterability via a self-passivation mechanism and loose interior structures. The hierarchical Cu architecture was prepared using copper hydroxide, L-ascorbic acid, and polyvinylpyrrolidone in aqueous solution; 40 g Cu were prepared in a scale-up experiment. A possible growth mechanism is proposed, involving the Cu2O-templated and mediated nucleation and growth of Cu nanocrystals, followed by the PVP-directed electrostatic self-assembly of Cu nanocrystals. The synthesized Cu shows high oxidation resistance after stored in ambient environment for 90 d by self-passivation, wherein the dense oxidized external layer prevented further oxidation of Cu, unlike other antioxidative strategies. In addition, the structure became 2D flake after a simple ball-milling for 10 min of 2000r, thus forming a good conductive network at the temperature of 180 °C. Importantly, no obvious decline in the electrical performance after severe surface oxidation. Although the structure cannot offer excellent conductive performance, but it proposes a new solution for the balance of antioxidative capabilities and good sinterability in Cu nanomaterials, thus facilitating greater utilization of Cu-based conductive inks for emerging flexible electronic applications.

Electrocatalysts based on transition metal sulfides (TMSs) are drawing accelerating concerns in renewable energy research because of their intrinsically excellent activities towards both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). To date, considerable efforts are made to improve the performance of these catalysts, but ignoring the improper synthesis strategy would incur additional cost to the catalyst. Herein, a convenient, one-step anodization method is developed for fast construction of cobalt sulfides (CoSx). Without any high-temperature or long-time treatment, mesoporous CoSx is self-grown on the metal substrate in minutes. As a result, as-anodic CoSx requires overpotentials of 102 mV for HER and 284 mV for OER to achieve a current density of 10 mA m−2 in alkaline solution. Moreover, the tandem bifunctional as-anodic CoSx exhibits a required cell voltage of 1.64 V for overall water splitting in alkaline solution, exceeding most of the documented Co-based electrocatalysts.

Remote control and targeted activation are the elevated goals for shape-memory and self-healing polymers when responses to stimuli. Among so many stimuli, converting light into microstructure change or mechanical motions is now of particular interest. Herein, we report the ingenious design, synthesis and operation to advanced materials that capable of fast near-infrared (NIR) light-actuated targeted shape memory and remote accurately self-healing. Starting from biomass resources, a well-defined polymer nanocomposite, CNTs-graft-poly(tetrahydrofurfury methacryla-co-lauryl acrylate-co-1-vinylimidazole) copolymer ((CNTs-g-P(TMA-co-LA-co-VI)), was fabricated by addition-fragmentation chain transfer (RAFT) polymerization. After subsequent metal-ligand crosslinking with Zn2+ ion, CNTs-g-P(TMA-co-LA-co-VI)/Zn2+ with CNTs content of 1.1 wt % have a maximum stress of 1.68 MPa and an elongation at break of 450%. Most importantly, the photothermal conversion of CNTs can effectively trigger the association and dissociation process of the dynamic metallosupramolecular crosslinked bond between VI and Zn2+, leading to excellent instantaneous multiple shape memory and accurate self-healing performance under NIR light or heat. This approach can be generalized toward de novo design of self-healing and shape memory nanocomposites with tunable mechanical properties.

The polymer composite electrolytes, especially garnet ceramic Li6.4La3Zr1.4Ta0.6O12 reinforced polyethylene oxide (PEO), are expected to be the most promising substitute for commercial liquid electrolytes in lithium metal batteries due to their good safety, easy-manufacturing and flexibility. However, their insufficient ionic conductivity and instability towards reductive Li anode at room temperature are the long-standing issues. In this work, a dual-salt solid composite electrolyte with superior ambient-temperature electrochemical performance is designed by regulating polyethylene oxide/lithium perchlorate/Li6.4La3Zr1.4Ta0.6O12 composite electrolyte with additive lithium tetrafluoroborate (LL@PL). The stable solid electrolyte interphase with LiF, B–F, and Li–B–O formed on lithium metal effectively induces even Li deposition and strengthens the compatibility of electrolyte/Li anode interface. The combined action of each composition in the electrolyte guarantees the efficient ion immigration kinetic and suppresses the lithium dendrite growth of solid-state batteries. The Li symmetric cells using LL@PL-0.1 can steadily cycle for 1700 h without short circuit. An 80% capacity retention is achieved for LiFePO4| LL@PL-0.1 |Li cell after 350 cycles at 25 °C. The electrochemical stability of the composite electrolyte is extended to 4.6 V and the assembled cell works well with LiNi0.8Co0.1Mn0.1O2 cathode. This study proposed a promising polymer composite electrolyte for solid-state lithium metal batteries with superior performance.

Form-stable phase change materials (FSPCMs) are widely used for cost-effective thermal management and energy storage applications. However, the strong rigidity of most FSPCMs at low temperatures and the weak resistance of them to damages when the temperature is exceeding their phase transition points have hindered their installations in limited places. Herein, we developed a novel kind of thermal regulation FSPCM possessing multiple phase change-stimulated shape memory and self-healing properties to address these issues. The synthesis of the FSPCMs is based on confining ethylene glycole distearate (EGDS) within the epoxy-based polymer matrix through photo-initiated polymerization. This strategy, on one hand, prevents the leakage of the liquid EGDS in macroscales, and on the other hand, maintains the mobility of the flowing EGDS in micro-scale regions to allow the FSPCM to perform shape deformation and recovery and enable self-repairing effects through solid-liquid phase transitions. Notably, the polymer matrix in the FSPCM consists of pre-grafted crystalline segments of stearic acid (SA) which improve the compatibility between the matrix and EGDS, and impart the FSPCM with multiple phase transitions to realize stepwise control of the shape memory behaviors. The resulting composite FSPCM also demonstrates good thermal regulation performance and high thermal reliability, which can be promisingly engineered into thermal management of integrated circuits and building glazing system with thermal regulation purpose.

The shell composition and microstructure of microencapsulated phase-change materials (MPCMs) are of vital significance for achieving high thermal and mechanical properties. Herein, a new type of MPCM with double-walled shells (melamine-formaldehyde (MF) resin/carbon nanotube (CNT)-poly(4-styrenesulfonic acid) sodium (PSS)) was developed through a facile layer-by-layer (LbL) self-assembly technique using prefabricated MF resin-encapsulated n-octadecane as the template. The CNTs were well dispersed and highly interconnected in the shell, which greatly enhanced the temperature response and thermal stability of MPCMs. Furthermore, the incorporation of 3.34 wt% CNTs resulted in an average hardness and Young's modulus of MPCMs, respectively, 3.3 and 1.3 times greater than those of microcapsules without CNTs. The double-walled MPCMs exhibited good potential for application in the field of thermal energy storage.

Luminescent water-induced shape memory polymer (SMP) composites with tunable shape recovery rate are developed by blending poly(vinyl alcohol) (PVA) and carbon quantum dots (CQDs). The oxygen and active hydrogen-rich CQDs can serve as extra physical cross-linking points in PVA via strong hydrogen bonding interaction, which largely improves the shape memory performances of PVA. At room temperature, water can successfully actuate the shape recovery of deformed PVA/CQDs composite. It is demonstrated that this water-induced shape recovery is mainly attributed to the plasticizing effect of water and its competitive hydrogen bonding. Furthermore, a quantitative bending test suggests that the shape recovery time of this water-induced SMP is tunable by altering the environmental pH value and temperature, and a relatively large shape recovery time window (from 20 to 200 s) can be achieved. In addition, the introduction of CQDs endows the PVA/CQDs SMP composites with excellent luminescent property, which makes the shape change of SMP visible under UV light. It should be noted that the mild stimulus condition and tunable shape recovery performances make the luminescent visible PVA/CQDs SMP feasible for diverse biological applications in smart medical devices, stimuli-responsive drug-release, and intelligent sensors in vivo and in vitro.

Monodisperse silver nanoparticles (Ag NPs) were facilely loaded on the inner and outer surface of hierarchical wrinkled mesoporous silica (WMSs) via an in situ chemical reduction, and the antibacterial capacity of the obtained nanocomposite was investigated in detail. Typical sulfydryl-functionalized wrinkled mesoporous silica nanoparticle with radical pore channels was firstly prepared through sol-gel technique with cetyltrimethylammonium bromide (CTAB) as the templating surfactant. After sulfonation of the as-prepared WMSs, Ag(+) ions were then densely locked up on the inner and outer surface of WMSs via electrostatic interactions. Well distributed Ag NPs (ca. 3-5nm) on WMSs without any agglomeration were finally obtained via a simple in situ reduction reaction with sodium borohydride. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) test indicated that the obtained products can achieve durable and much better antibacterial performance both against Gram-negative bacterium Escherichia coli (E. coli) and Gram-positive bacterium Staphylococcus aureus (S. aureus) comparing to pure colloidal silver nanoparticles, which rendered them as favorable candidate for the development of effective antibacterial agents.

We report a simple "one-pot" solvothermal preparation of silver nanoparticles (Ag NPs) decorated mesoporous titania (TiO2) microspheres as an effective antibacterial agent. TBOT as Ti source was hydrolyzed and crystallized in media composed of acetic acid and ethanol, in which esterification catalyzed by TBOT occurred for in-situ "controlled water release". AgNO3 as Ag source was reduced by ethanol to form Ag NPs embedded in the TiO2 microspheres. The effect of AgNO3 and HAc on the morphology of Ag/TiO2 was investigated. The Ag/TiO2 with various Ag content showed excellent antibacterial activities with extremely low minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Escherichia coli and Staphylococcus aureus when compared with colloidal Ag NPs.

In this study, amino functionalized poly glycidyl methacrylate (am-PGMA) based microspheres prepared via soap-free emulsion polymerization were served as polymeric matrices for silver nanoparticles (Ag NPs) loading and applied as anti-bacterial agent. The amino and hydroxyl enriched am-PGMA based microspheres served as both matrix for Ag+ absorbance through coordination bond and reduce agent under hydrothermal condition in a high-pressure steam sterilization. The effects of chemical structure of microspheres on the morphology of Ag NPs/polymer composites were investigated. Am-PGMA/Ag composite spheres with ultra-fine Ag NPs up to 26 wt% were well characterized and their antibacterial activity were studied and discussed in detail. It was found that the Ag NPs loading in microspheres showed comparable anti-bacteria activities in terms of Ag with the minimum inhibitory concentration (MIC) low to 20 and 20 mg/L (equal to 5.2, 5.2 mg/L Ag) for Escherichia coli and Staphylococcus aureus respectively. The obtained composites spheres (am-PGMA/Ag) are promising alternative anti-bacterial agents in industrial and biomedical applications.

Facing upon the increasingly severe energy crisis, one of the key issues for reducing the building energy consumption is to pursue high-performance thermal energy storage technologies based on phase-change materials. In this study, a novel cement composite incorporated with flaky graphite-doped microencapsulated phase-change materials (FGD-MPCMs) was developed. Various techniques, such as field emission-scanning electron microscopy (FE-SEM), optical microscopy (OM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to analyse the composite structure and thermal performances. The results indicate that the spherical microcapsules are well dispersed in the cement matrix. When combined within the cement, the thermal stability of the microcapsules was highly improved, and the inclusion of greater amounts of FGD-MPCMs further increased the latent heat of the composite. The mechanical properties of the cement composites were affected with the increase of FGD-MPCMs dosage and the porosity of the composites. In spite of this, the compressive strength and flexural strength of the cement composite with 30% FGD-MPCM could still reach to as high as 14.2 MPa and 4.1 MPa, respectively. Results from the infrared thermography and the model room test suggested that the composite filled with FGD-MPCMs is capable of reducing indoor temperature fluctuation and exhibits good potential for application in buildings to enhance energy savings and thermal comfort.