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Transition metal sulfides with designed nanostructures are expected to provide superior electrochemical performance when used as electrode materials for pseudocapacitors compared to their oxide counterparts. In this paper, hollow Co3S4 dodecahedra were successfully prepared using cobalt‐based zeolite imidazolium skeleton (ZIF‐67) as the precursor and thioacetamide (TAA) as the sulfur source combined with a facile one‐step vulcanization process. The hollow cavity structure not only shortens the carrier transport distance but also provides a higher specific surface area and abundant active sites, which promotes an efficient mass transfer process. In addition, the one‐step synthesis of hollow Co3S4 has greater advantages than the one‐step synthesis in terms of cost control and process simplification. The specific capacitance of the produced hollow Co3S4 nanopolyhedra was 668 F/g at 1 A/g and remained at 353 F/g at 10 A/g when used as a pseudocapacitor electrode, demonstrating its superior multiplication capability. In addition, the capacitance retention is 86.4% after 5000 cycles at 4 A/g, indicating its long cycle stability. Notably, employing commercial activated carbon as negative electrode and the as‐prepared hollow Co3S4 polyhedrons as positive electrode, the assembled asymmetry supercapacitor device delivers a high energy density of 20.7 Wh/kg at a power density of 716 kW/kg. The capacitance value of the device remains up to 81.4% after 2000 charging/discharging cycles. The simple synthesis process opens new opportunities to develop advanced hollow nanostructures exhibiting potential for various applications. [ABSTRACT FROM AUTHOR]

The past decades have witnessed the rapid development of lithium-ion batteries (LIBs), which are applied in nearly every aspect of our daily life. However, the increasing number of spent LIBs (S-LIBs) poses a great threat to the environment. Thus, to protect the environment and preserve limited lithium resources, it is necessary to recycle S-LIBs. In this review, we initially provide a brief introduction on the structure and degradation mechanism of LIBs and pretreatment of S-LIBs. Subsequently, we highlight the recent advancements in the development of recycling the cathode of S-LIBs, including its direct, hydrometallurgical, and pyrometallurgical recovery. The advantages and disadvantages of each recycling process are also discussed from the viewpoint of the environment and economy. In addition, we also introduce the recycling of S-LIBs through a green and environmentally friendly process of treating waste with waste. Finally, the overall perspective of this technology and areas requiring particular attention in the future are discussed. [ABSTRACT FROM AUTHOR]

Hierarchical core–shell structure is benefit for the fast diffusion and bulk storage of electron/ion while metal nitrides (MN) exhibit metal‐like behavior with excellent conductivity. Herein, nickel cobalt glycerate solid spheres (NiCo‐G) and nickel cobalt glycerate yolk–shell structure (NiCo‐GYS) were successfully synthesized via solvothermal reactions, accompanied by annealing using urea as a cheap and convenient nitrogen source to obtain metal nitride/bimetallic oxide core–shell heterostructure (NiCoNO). Excellent specific capacitance of 1878 F g−1 at 1 A g−1 is displayed by the prepared NiCoNO. Amazingly, the distinct core–shell construction guarantees high stability during the charge/discharge operation. NiCoNO maintains an 83.9% specific capacitance after 5000 cycles at 10 A g−1. Furthermore, the all‐solid‐state hybrid supercapacitor was assembled using NiCoNO cathode and active carbon (AC) anode components. The device has an excellent capacitive retention rate of 81.1% after 5000 cycles at 10 A g−1 and a good energy density of 64.2 Wh kg−1 at a power density of 900 Wh kg−1. A light‐emitting diode (LED) bulb can be lighted for 3 min, indicating the promising practical application prospect of the supercapacitor. [ABSTRACT FROM AUTHOR]

Carbon-based materials have demonstrated excellent thermal, electric, optical, magnetic, and mechanical properties, offering promising application potential in many fields. Corresponding synthetic approaches meeting the requirements of sustainable development goals are always desired. Compared with chemical vapor deposition, solvothermal, conventional pyrolysis, and salt-assisted methods are emerging as advanced synthetic technologies for the fabrication of carbon-based materials since these processes are expected to be more sustainable. Herein, we provide a comprehensive review on the salt-assisted synthesis of carbon-based materials and their typical energy-related applications. First, the properties of carbon and a comparison of various synthetic techniques are briefly introduced. In particular, we highlight the advantages of salt-assisted synthesis in view of sustainable development goals. For convenience, we divide the roles of salt in assisting the synthesis of carbon-based materials into four subclasses: reaction medium, pore-forming agent, morphology control, and precursors. Simultaneously, the applications of these carbon-based materials in energy-related fields are discussed. Lastly, the major challenges in this field are outlined, and future research avenues in salt-assisted synthesis of carbon-based materials for energy-related applications are also highlighted. It is expected that this tutorial review will supply necessary background information to further advance salt-assisted synthesis of carbon-based materials for energy-related applications. [ABSTRACT FROM AUTHOR]

The construction of electrode materials with high rate and excellent cycling stability is the key to supercapacitors. Due to their remarkable high conductivity and great electrochemical activity, transition bimetallic sulfides are extremely appealing electrode materials for supercapacitors, but their synthesis is still challenging. In this study, a NiCo bimetallic sulfide (NiCo2S4) microspheres with porous structure were prepared via direct vulcanization of NiCo‐EG complexes followed by a thermal treatment, which were pre‐synthesized via coordination of ethylene glycol (EG) with transition metal ions (Ni2+, Co2+) under hydrothermal condition. Some experimental parameters were investigated, including the control of NiCo2S4 microspheres produced by the ratio of precursor NiCo‐EG to different masses of sulfur sources, which in turn affects the electrochemical properties. When applied as electrode for supercapacitor, the NiCo2S4 microspheres obtained under optimal condition delivered a high capacitance (1386 F g−1 at 1 A g−1), excellent rate capability (845 F g−1 at 10 A g−1) and stable cycling performance (80.05% after 5000 cycles at 10 A/g). Furthermore, for checking the practicality of the produced NiCo2S4 microspheres, an asymmetric supercapacitor device was built using activated carbon (AC) as the negative electrode and NiCo2S4 microspheres as the positive electrode. The assembled NiCo2S4//AC cell had a power density of 799.9 W kg−1 and an energy density of 30.5 Wh kg−1, confirming that the structurally optimized NiCo2S4 porous nanomicrospheres have excellent electrochemical properties and have a wide range of application prospects. [ABSTRACT FROM AUTHOR]

To address the rising challenges in self-controlled tandem processes, a catalytic reactor with two reversely-responsive layers was fabricated, for which the two layers acted as the carriers of two different-type active sites so as to achieve the adjustable catalytic ability. This first layer was a shape-memory copolymer consisting of 2-acrylamido-2-methylpropane sulfonic acid and 1-heptene. Given the "frozen" domains in the copolymer at low temperatures, the channel of the substrate became closed. At middle temperatures, the channel of the substrate became open as a result of the activation of the copolymer. The second layer was a copolymer embedding Ag nanoparticles made of polymeric 2-(trifluoromethyl) acrylic acid and 2-vinylpyridine. This layer showed the "closed" channel at low temperatures due to the electrostatic interactions between the two polymeric components, which inhibited the entry of reactants. At higher temperatures, as the polymeric interactions at this layer were broken, the channel in this layer became open for the reactants. In combination with the contained acidic sites and catalytic Ag nanoparticles sites in the two layers, which were individually responsible for catalytic hydrolysis and reduction, the reactor did not show substantive catalytic ability at low temperatures due to the closed channels in both the two layers. At middle temperatures, the reactor ran with simple hydrolysis due to the open channel in the first layer which contained acidic sites. At higher temperatures, the reactor ran with tandem catalytic processes because of the open channels in the two layers. Hence, the design of the dual-responsive catalytic reactor acquired the non-tandem/tandem self-controlled catalytic ability. [ABSTRACT FROM AUTHOR]

A large number of species in nature demonstrate switchable responsiveness to external stimuli, which is essential for their adaptation to the changing environment. Inspired by the responsive properties in nature, researchers have made significant progress in the field of synthetic stimuli-responsive materials over the years, particularly in the field of smart polymer catalysts which are able to control the catalytic processes. Here, we review these bio-inspired polymer materials and their applications in self-controlled catalytic processes. Other issues involved in developing these bio-inspired polymer materials including the origin, mechanisms, switchable behaviors and merits are also discussed. [ABSTRACT FROM AUTHOR]

Abstract The combination of carbon and iron oxide has recently attracted increasing research interest in energy conversion and storage. Here, the hybrid nanostructure with N, S-codoped Fe 3 O 4 supported/embedded on/in N-doped porous carbon (NS-Fe 3 O 4 @N-PC) nanococoon was prepared via direct pyrolysis of core@shell β-FeOOH@Polypyrrole (β-FeOOH@PPy) composite. Benefiting from the synergistic effect of high redox activity of NS-Fe 3 O 4 and excellent electrical conductivity as well as good mechanical stability of N-PC, the obtained NS-Fe 3 O 4 @N-PC exhibited an enhanced specific capacitance of 866 F/g at 1 A/g along with excellent rate capability (383 F/g at 10 A/g) and improved cycling stability (78.2% of initial capacitance retained after 5000 cycles test) while applied as electrode materials of supercapacitor. Significantly, the asymmetric supercapacitor devices assembled using NS-Fe 3 O 4 @N-PC as anodes and commercial carbon nanotubes as cathodes can achieve a large stack energy density of 38.9 Wh/Kg at a stack power density of 700.2 W/Kg along with good stability (only 8.4% decay of initial capacitance after 5000 cycles at 4 A/g). The present work may provide a general approach for fabricating other metal oxide@carbon hybrid nanomaterials for various applications. Graphical abstract Unlabelled Image Highlights • Core@shell structured β-FeOOH@polypyrrole nanospindle was synthesized via an in-situ polymerization method. • NS-Fe 3 O 4 @N-PC composites were synthesized by pyrolysing β-FeOOH@polypyrrole. • The electrochemical performances to β-FeOOH, β-FeOOH@polypyrrole, and NS-Fe 3 O 4 @N-PC were investigated. • The NS-Fe 3 O 4 @N-PC//CNTs delivers a large stack energy density of 38.9 Wh/Kg at a stack power density of 700.2 W/Kg. [ABSTRACT FROM AUTHOR]

The realization of selective/nonselective-switchable catalytic ability remains a significant challenge in controlled catalytic processes. We herein report an originally-designed imprinted polymer nanoreactor capable of meeting this challenge. This nanoreactor was composed of Ag nanoparticles and a unique holothurian-inspired imprinted polymer carrier that contained mobile molecular chains. These mobile molecular chains, by motioning and lying motionless, enabled the imprinted carrier to function in an 'online/offline'-shiftable paradigm, causing switchable access to the encapsulated metal nanoparticles. This nanoreactor showed selective catalytic ability at relatively low temperatures due to the 'frozen' molecular chains, which allowed for substrate-selective access to the encapsulated metal nanoparticles (i.e., imprinted carrier's 'online' status). In contrast, this nanoreactor provided non-selective catalysis at relatively high temperatures in response to the increased mobility of these molecular chains, which resulted in dismantling the selective access (i.e., imprinted carrier's 'offline' status). Unlike reported imprinted polymer nanoreactors which simply provide selective catalysis, this novel nanoreactor allows selective/nonselective-switchable catalysis in virtue of the bio-inspired design. This study opens up opportunities to modulate catalytic selectivity for controlled chemical processes. [ABSTRACT FROM AUTHOR]

This study aimed at the present challenge in self-controlled catalysis, addressing how to furnish the catalysts with sortable catalytic ability. This objective was reached by developing a polymer catalyst made of metal nanoparticles and a unique polymer carrier containing self-assembled hierarchical access. The hierarchical access, by closing, relaxing and opening, acted as a molecular switch for providing sequenced entrance to the encapsulated metal nanoparticles. This polymer catalyst showed poor catalytic reactivity at relatively low temperatures due to the closed access, which blocked substrate from the encapsulated metal nanoparticles. This polymer catalyst showed, however, significant reactivity for small molecules of substrate at modest temperatures, arising from relaxing of the access, which allowed small molecules to gain entrance to the catalytic metal nanoparticles. This polymer catalyst further showed significant reactivity for large molecules of substrate at relatively high temperatures, in response to the opening at the access. In this way, this polymer catalyst demonstrated the sortable catalytic ability. This suggested protocol opens up the opportunity to develop smart catalysts for controlled chemical processes. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) is one of the most important plastics derived from petroleum, which has been extensively used in everyday life for the last few decades due to its superior properties. Without reasonable manageability, the volume of PVC is increasing steadily in the natural world. Owing to its features of non-biodegradability, the traditional disposal of PVC waste by either pouring it into the oceans or landfilling causes serious environmental issues. Due to sustainable development, PVC solid waste can be recycled to obtain products with the same quality as the starting material, reused in other fields, or converted into other high-value chemicals. Over the past decades, great progress has been made in the recycling of PVC. In this review, we initially provide a brief introduction to PVC, including its chemical structure, annual production and application fields, followed by an overview of mechanical approaches, including separation techniques, inclusion in other materials, and non-conventional mechanical recycling. The advantages and disadvantages of these techniques are also considered. Various chemical approaches to converting PVC waste into new products or chemicals to enhance the sustainability of the environment, such as gasification, pyrolysis, and de-chlorination are discussed in detail. Finally, the challenges and future perspectives of recycling PVC solid waste are discussed. [ABSTRACT FROM AUTHOR]

In this study, rod-shaped akaganeite nanostructures were successfully synthesized via a facile hydrothermal process using polyvinylpyrrolidone as the soft template and NaAc as the precipitation agent. The electrochemical properties of the as-prepared akaganeite nanorods were investigated by cyclic voltammetry, galvanostatic charge-discharge, and constant current discharge. The results reveal that the as-prepared akaganeite nanorods exhibit high specific supercapacitance of 1,140 F g Graphical Abstract: Rod-shaped akaganeite (FeOOH) nanostructures, synthesized via a facile hydrothermal process, show very high supercapacitance.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This study was aimed at addressing the present challenge of cascade reactions, namely, how to furnish the catalysts with desired and hierarchical catalytic ability. This issue was addressed by constructing a cascade-reaction nanoreactor made of a bifunctional molecularly imprinted polymer containing acidic catalytic sites and Pt nanoparticles. The acidic catalytic sites within the imprinted polymer allowed one specified reaction, whereas the encapsulated Pt nanoparticles were responsible for another coupled reaction. To that end, the unique imprinted polymer was fabricated by using two well-coupled templates, that is, 4-nitrophenyl acetate and 4-nitrophenol. The catalytic hydrolysis of the former compound at the acidic catalytic sites led to the formation of the latter compound, which was further reduced by the encapsulated Pt nanoparticles to 4-aminophenol. Therefore, this nanoreactor demonstrated a catalytic-cascade ability. This protocol opens up the opportunity to develop functional catalysts for complicated chemical processes. [ABSTRACT FROM AUTHOR]

This study aimed at the present dilemma in selective catalysis, about how to furnish metal-nanoparticle catalysts with predictable selectivity. This issue was addressed by developing a 'key-vs.-lock'-like polymer reactor made of an elaborate molecularly imprinted polymer containing metal nanoparticles, which was capable of predictably and selectively catalyzing its specified substrate. Unlike reported polymer reactors and enzyme-like imprinted polymer catalysts, which lack either predictable selectivity or reactive metal nanoparticles, this polymer reactor has incorporated both of the molecular recognition ability of the polymer carrier and the catalytic sites of metal nanoparticles into one entire entity and thereby dictated selective catalysis. This study highlighted how this polymer reactor works in a selective way in contrast to reported catalytic polymers or polymer reactors, which thus opens opportunities of tailoring selective catalysts for controlled chemical processes. [ABSTRACT FROM AUTHOR]

The present endeavor is to develop a highly-intelligent catalytic reactor prototype which is able to autonomously adapt to the environment and provides an in-situ double-shift catalytic ability. By seeking inspiration from nature, this objective is achieved by developing a self-adaptive hydrogel catalytic reactor which held a catalytic trilaminar structure capable of reverse thermosensitive properties. With increasing temperatures, the catalytic tri-layers of this catalytic reactor would function in a sequential way (i.e., one negative temperature response layer, one support layer and one positive temperature response layer) and as a result, led to the single-tandem double-shift catalytic ability. This catalytic reactor individually presented single/tandem catalytic process at relatively low temperatures or high temperatures through the cooperative work of the three layers. In this way, this catalytic reactor showed the single-tandem controllable catalytic ability. The novel protocol not only provides a new solution to complicated catalytic processes but also inspires the further application of smart polymers in a broader spectrum of areas. [ABSTRACT FROM AUTHOR]

This study is aimed at addressing the present challenges of self-controlled processes in tandem catalysis. Inspired by the opening and closing switchable behaviors of stomata in plant leaves arose by temperature, the objective is met by originally developing a "smart" tandem catalyst capable of crossing-response properties. The catalyst consisted of two unique functional layers where each may self-govern one coupled process. The first layer was fabricated with a negatively-thermosensitive imprinted polymer and encapsulated metal nanoparticles (PDEA- co -PAM/Ag) which were responsible for a catalytic reduction process. The second layer was made of a positively-thermosensitive polymer (PVI- co -PAMPS) with acidic groups, which were capable of a catalytic hydrolysis process. At low temperatures, this catalyst would conduct only catalytic reduction because of the open channel in the first layer. In middle temperatures, the catalyst would run the tandem processes from catalytic reduction to hydrolysis because of the open channels in both the two layers. At higher temperatures, the catalyst only catalyzed hydrolysis because of the closed channel in the first layer. In this way, the smart bi-layer catalyst achieved the single/tandem/single catalysis featured with a dual temperature-responsive switch. The novel protocol not only provides a new solution to complicated catalytic processes but also inspires the further application of smart polymers in a broader spectrum of areas. The switchable mechanism of the polymer reactor. [Display omitted] • Thermo-sensitive tandem catalyst is able to adapt to the changing environment. • A "smart" tandem catalyst is capable of crossing-response properties. • The catalyst is able to conduct the single/tandem/single reactions in different temperatures. • New catalyst shares a promising prospect to the development of one-pot catalytic processes in applications. [ABSTRACT FROM AUTHOR]

Here, we developed a lotus-leaf-resembling superhydrophobic coating with sturdy abrasion and weather resistance. By taking the sturdiness of the superhydrophobicity into account, this coating was created by incorporating a zinc-mediated superhydrophobic surface that was rough and ultraviolet-resistant into a polyurethane layer capable of strong wear resistance. By spraying the zinc-mediated perfluorosilane and a polyurethane suspension onto an aluminum flake, the lotus-leaf-resembling superhydrophobic coating was thus prepared. The resulting coating displayed the natural superhydrophobic phenomena with a contact angle of up to 157.1° and a rolling angle of 4.2°, greater or smaller by depending on the dosage of zinc. The adoption of zinc to the prepared coating not only mediated the rough surface texture but also extra granted the ultraviolet resistance. In couple with the strong wear resistance of the substrate layer, the proposed superhydrophobic coating provided the expected sturdy abrasion and weather resistance. The development of the superhydrophobic coating shares a prospect with practical applications, especially outdoor applications. [ABSTRACT FROM AUTHOR]

Intelligent devices, when subjected to multiple interactions, tend to generate electromagnetic pollution, which can disrupt the normal functioning of electronic components. Ferrite, which acts as a microwave-absorbing material (MAM), offers a promising strategy to overcome this issue. To further enhance the microwave absorption properties of ferrite MAM, numerous works have been conducted, including ion doping and combining with other materials. Notably, the microstructure is also key factor that affects the microwave absorption properties of ferrite-based MAM. Thus, this article provides a comprehensive overview of research progress on the influence of the microstructure on ferrite-based MAM. MAMs with sheet and layered structures are also current important research directions. For core-shell structure composites, the solid core-shell structure, hollow core-shell structure, yolk-eggshell structure, and non-spherical core-shell structure are introduced. For porous composites, the biomass porous structure and other porous structures are presented. Finally, the development trends are summarized, and prospects for the structure design and preparation of high-performance MAMs are predicted. [ABSTRACT FROM AUTHOR]

Over a century ago, phenolic formaldehyde (PF) resin was developed and continues to increase in yield due to its diverse applications. However, PF resin is a thermosetting plastic lacking fluidity and moldability, which are nondegradable in natural environments, leading to severe threats to fossil resources as well as global environmental crises. As a result, recycling PF resin is extremely important. In this review, we provide the recent advances in the recycling of PF resin, which includes mechanical recycling, chemical recycling, and utilization of carbon-based materials. The advantages and disadvantages of each strategy are evaluated from a green chemistry perspective. This article aims to attract interest in PF resin design, synthesizing, application and recycling, offering useful suggestions. [ABSTRACT FROM AUTHOR]

Zn-BTC (H3BTC refers to 1, 3, 5-benzoic acid) MOF was used as a self-template and a zinc source to prepare ZnS/NiS2 with a layered heterogeneous structure as a promising electrode material using cation exchange and solid-phase vulcanization processes. The synergistic effect of the two metal sulfides enhances the application of ZnS/NiS2. And the high specific surface area and abundant active sites further promote the mass/charge transfer and redox reaction kinetics. In the three-electrode system, the specific capacitance was as high as 1547 F/g at a current density of 1 A/g, along with satisfactory rate capability (1214 F/g at 6 A/g) and cycling performance. Coupled with activated carbon (AC), the prepared hybrid device (ZnS/NiS2 as the positive electrode and AC as the negative electrode) (ZnS/NiS2/AC) can be operated under a potential window of 1.6 V and provides a high energy density of 26.3 Wh/kg at a power density of 794 W/kg. Notably, the assembled ZnS/NiS2//AC showed little capacity degradation after 5000 charge/discharge cycles. [ABSTRACT FROM AUTHOR]

This study is aimed at the present challenge in self-controlled catalysts, addressing how to furnish the catalysts with cascade/non-cascade-switchable catalytic ability. By borrowing the "soft" properties and autonomous ability from nature, this objective was met by reporting an artificial polymer reactor that was composite of tri-layer architectures made of two inversely-thermosensitive outward layers and a non-responsive middle layer. With the middle layer containing catalytic metal nanoparticles, the two thermosensitive outward layers consisted separately of a negatively-temperature responsive polymer and a positively-temperature responsive composite. The opposite responsiveness at the two thermosensitive outward layers induced convex/flat/concave-switchable shapes in this reactor, leading to cascade/non-cascade-alterable substrate channeling to the reactive middle layer. In this way, this polymer reactor led to the occurrence of cascade/non-cascade-switchable catalytic ability. This design shares a promising prospect with the struggling field of self-controlled catalysts, which allows opportunities to finely control catalytic processes. [ABSTRACT FROM AUTHOR]

Inspired by the polymeric "soft" properties and divisional isolation of tandem processes in natural systems, an artificial reactor with self‐screened catalytic ability was fabricated with a polymeric tri‐layer architecture. The non‐responsive middle layer encapsulated catalytic metal nanoparticles, while the two outer layers consisted of a negatively and a positively thermosensitive imprinted polymer. The inverse responsiveness of the outer layers induced switchable shapes, which led to alterable tandem channeling to the reactive middle layer and, as a result, the divisional admission of different substrates. This way, the reactor led to the formation of self‐screened catalytic ability. The design for this artificial reactor offers promising prospects for struggling tandem catalysts, suggesting opportunities to develop schedulable tandem processes. [ABSTRACT FROM AUTHOR]

Carbon materials play an important role in supercapacitors due to their structural diversity, rich surface morphology, excellent chemical stability and highly active surfaces. Currently, there are many reports on the synthesis methods for carbon-based materials. The molten salt method stands out among the many methods for its advantages of economy, environmental protection, high efficiency, and maneuverability. Here, we focus on the different roles played by molten salts as templates, sealants, reaction media, and catalysts from the point of view of their functions. The properties and selection principles of the molten salts are discussed in depth, focusing on the morphology, structure, and capacitive properties of the carbon materials prepared using the molten salt strategy. Finally, the current research status of the preparation of carbon-based materials by the molten salt method is summarized, the shortcomings of existing technology are pointed out, and the prospects for its development are envisioned. It is hoped that this review can provide some basic knowledge for the preparation of carbon-based materials by the molten salt method and promote further research on molten salt technology. [ABSTRACT FROM AUTHOR]

A silver selective electrode based on TEPQA‐MCM‐41 material was developed and used for the selective determination of Ag+ ion in various samples. The effect of various plasticizers i. e. dimethyl phthalate (DMP), Tris(ethylhexyl)phosphate (TEP), bis‐(2‐ethylhexyl)sebacate (BEHS), bis‐(2‐ethylhexyl)adipate (BEHA) was investigated. The electrode of the composition of 2 : 1 : 77 : 12 : 8 (w/w, %) of TEPQA‐MCM‐41 : NaTPB : Graphite powder : paraffin oil : DMP respectively, works satisfactorily in a wide concentration range of 1.3×10−9 M–1.0×10−1 M for Ag+ ion with a lower detection limit (LOD) of 1.0×10−9 M and has Nernstian slope of 63.4± 1 mV/decay. The electrode can be used in a pH range of 2.3 to 6.7 for a period of 3 months without any divergence in potential response. The selectivity coefficient calculated by fixed interference method indicates the high selectivity of the electrode towards Ag+ ion over other tested cations. [ABSTRACT FROM AUTHOR]

In this study, we report the preparation of a lotus-leaf-like coating with robust super-hydrophobicity and anti-ultraviolet ability. As theoretically decoded from quantum mechanics, the combination of ceria-modified roughness with a substrate layer with low surface energy may help narrow the water-"hit" moiety on the surface and accordingly enhance the super-hydrophobicity, along with the intrinsic ultraviolet-resistant ability of ceria. To the end, this coating was fabricated by spraying a ceria emulsion and a perfluorosilane emulsion of the substrate layer onto a glass slide that helped form the lotus-leaf-like rough surface. Depending on the content of ceria, the prepared coating demonstrated the desired and excellent superhydrophobic properties in which the contact angle can be up to 155.7° and the rolling angle can be up to 4.8°. The presence of ceria in the prepared lotus-leaf-like coating not only enhanced the super-hydrophobicity but also dictated the anti-ultraviolet ability. In conjunction with the sturdy wear resistance, the successful preparation of this coating suggests a promising prospect for practical applications and particularly outdoor applications. [ABSTRACT FROM AUTHOR]

This study is aimed at booming intelligent catalysts, suggesting a bio-inspired polymer catalyst with catalytic substrate-sieving ability. By mimicking the hierarchical multi-level structures in biopolymers, this polymer catalyst was fabricated with metal nanoparticles and double "zipper" conformations individually made of polymeric hydrogen bonds and complexing interactions. Owing to the discrepant strength of both interactions against temperature, the double zipper conformations led to a hierarchical disruption of the two interactions and the stepwise disaggregation of the polymeric networks and as a result the substrate-sieving ability. This catalyst didn't present effective catalysis at low temperatures because of the blocked networks. With the increasing temperatures, this catalyst would first present catalysis towards small molecules of substrate and then further towards bigger molecules of substrate, by virtue of the hierarchical disruption of the weaker hydrogen bonds and the stronger complexing interactions. In this way, this catalyst assumed the substrate-sieving ability. The protocol of this catalyst suggests a prospect to modulate the catalytic proceedings, particularly for complicated processes. [ABSTRACT FROM AUTHOR]

• A novel Zr-MOF-NH 2 /CTF-Cu2+ hybrid was prepared for NO 2 and SO 2 adsorption. • Diverse synergistic effects of Zr-MOF-NH 2 /CTF-Cu2+ lead to outstanding performances. • Zr-MOF-NH 2 /CTF-Cu2+ exhibits better adsorption performance compared with AC. Benefiting from the structural diversity, high porosity, controllable pore and functional design, porous organic frameworks (POPs) are attracting great attention in adsorption areas. In particular, metal–organic frameworks (MOFs) and covalent-organic frameworks (COFs) have exhibited fascinating potential in gas adsorption. However, in practical application, because the dominant micropores are unfavorable to the transport and diffusion of gas molecules, coupled with the unstable structure stemmed from weak coordination bonds, MOFs are restricted, while COFs are limited by the lack of sufficient active sites. The complementary advantages between MOFs and COFs provide ideas for designing novel hybrid frameworks. Here, a covalent triazine-based framework (CTF) was chosen as skeleton to in situ synthesize Zr-MOF-NH 2 , constructing an interpenetrated MOF/CTF hybrid. Further, Cu2+ ions were introduced to endow the hybrid with more active centers, resulting in a hierarchical porous Zr-MOF-NH 2 /CTF-Cu2+. The synergistic effect between MOF and CTF, coupled with Cu2+ active centers, endows the Zr-MOF-NH 2 /CTF-Cu2+ hybrid with exceptional adsorption performance for harmful acidic gases. The adsorption capacities of Zr-MOF-NH 2 /CTF-Cu2+ for SO 2 and NO 2 are 39.3 mg g−1 and 27.3 mg g−1, which are 2.6 and 3.1 times as high as that of Zr-MOF-NH 2 , respectively. Meanwhile, the breakthrough times of Zr-MOF-NH 2 /CTF-Cu2+ for SO 2 and NO 2 are 252.8 and 187.6 min, which are approximately 1.9 and 2.3 times as long as that of pristine MOF, respectively. [ABSTRACT FROM AUTHOR]

How to furnish catalysts with switchable catalytic ability is a challenge in self-controlled catalysis. This issue was addressed by constructing a unique polymer nanoreactor containing 'mobility-recalling' switchable domains that acted as a molecular switch for providing access to the encapsulated metal nanoparticles. This polymer reactor revealed poor reactivity at relatively low temperatures because of the 'frozen' molecular chains in the switchable domains inhibiting the access of substrate to the encapsulated metal nanoparticles (i.e., catalytic 'off' status). In contrast, the polymer reactor demonstrated significant reactivity at relatively high temperatures, resulting from the dramatically increased mobility of the molecular chains, which allowed access to the encapsulated nickel nanoparticles (i.e., catalytic 'on' status). Switching between the catalytic off and on statuses could be repeated owing to the recallable mobility of molecular chains in the switchable domains. This protocol opens up the opportunity to develop smart nanoreactors for controlled chemical processes. [ABSTRACT FROM AUTHOR]

This study is aimed at booming intelligent polymers and their applications in catalysis, presenting an intelligent polymer catalyst with photo-mediated catalytic ability. This catalyst was fabricated with polymeric 2-acrylamide-2-methylpropylsulfonic acid (acidic moieties capable of catalytic hydrolysis) and photo-sensitive acrylamide-azobenzene prepared from the synthesis of 4-aminoazobenzene with acryloyl chloride. Under the radiation of ultraviolet light, this catalyst would undergo a change of cis/trans-conformation of azobenzene, causing alterable accessibility to the internal catalytic sites and as a result mediated catalytic ability. This catalyst presented significant catalytic ability at ambient conditions due to the trans-conformation of azobenzene which endorsed accessibility to the internal catalytic sites. Conversely, this catalyst showed limited catalytic ability under ultraviolet light, in response to the isomerization of the cis-conformation of azobenzene which inhibited the accessibility. In this way, this catalyst showed the photo-mediated catalytic ability. The suggestion of this polymer catalyst provides a prospect to optically modulate the catalytic proceedings, particularly for complicated processes. [ABSTRACT FROM AUTHOR]

An originally designed catalytic and shape-memory polymer reactor is reported. This reactor is made of a unique shape-switchable polymer composed of a thermosensitive control layer and an inert substrate layer. With the inert substrate layer made of poly(acrylamide), the thermosensitive control layer consists of nickel nanoparticles and a smart polymer composite of poly(1-vinylimidazole) (PVIm) and poly(acrylic acid) (PAAc) that exhibit switchable domains. The self-healing and dissociation between PVIm and PAAc induce convex/concave-switchable shapes in the resulting reactor, which cause tunable access to the encapsulated metal nanoparticles. In this way, this reactor demonstrates tunable catalytic ability. Unlike reported smart polymer reactors exhibiting tunable catalysis usually due to the thermal phase transition of poly(N-isopropylacrylamide) (PNIPAm), this novel reactor adopts the shape-switchable strategy for tunable catalysis. This novel design suggests a new protocol for the development of smart catalytic reactors, which opens new opportunities for controlled chemical processes. [ABSTRACT FROM AUTHOR]

A smart catalytic reactor capable of simple/tandem-commutative catalytic ability was reported here. By borrowing the natural soft morphology and segregated zones in biosystems, this reactor was constructed with polymeric bilayer composites where each constituted a catalytic zone. The combination of the two catalytic zones with a catalytically-coupled process would dictate the reactor sequential catalytic behaviors and accordingly simple/tandem-commutative catalytic ability. To that end, one of the layers in this reactor was fabricated with acidic architectures capable of catalytic hydrolysis whereas the other layer was made of a thermo-sensitive antibody-like imprinted hydrogel which acted as a switch to provide access for the succeeding reaction. In this way, this reactor demonstrated the simple/tandem-commutative catalytic ability. This suggested design shares a promising prospect with developing functional catalysts and programmable catalytic processes. [ABSTRACT FROM AUTHOR]

Yolk@shell nanocomposites with delicate composition and tailored structure usually exhibit great potential in various areas. In the present study, the synthesis of yolk@shell Fe 3 O 4 @MnO 2 microspheres was reported using core@shell Fe 3 O 4 @polydopamine (Fe 3 O 4 @PDA) as starting materials. This novel approach is based on the reductive property of the PDA derived carbon shell. The new shell of MnO 2 was synthesized by reaction of PDA derived carbon and KMnO 4. The Fe 3 O 4 @MnO 2 yolk@shell microsphere was successfully used as electrode material for supercapacitor and delivers a high specific capacitance of 715 F/g at 1 A/g with a good rate capability (450 F/g at 10 A/g). Furthermore, the Fe 3 O 4 @MnO 2 yolk@shell microsphere was also used as the positive electrode for asymmetric supercapacitors (ASC), wherein N doped carbon from PDA was applied as negative electrode. As a result, the energy density of the constructed ASC device was up to 31.3 Wh/kg at a power density of 750 W/kg. Meanwhile, the Fe 3 O 4 @MnO 2 //N-pC (PDA derived N-doped porous carbon) device offers an excellent cycling stability (94.7% of capacitance retention after 5000 cycles). Such distinguish capacitive performance is undoubtedly related to the electrochemical actuation of the yolk@shell microsphere structure and their structural integrity, where the void between the shell and yolk may relieve the volume change of the electrode. Considering the efficiency and simplicity of the synthetic procedure, it is expected that the present method might be suitable for preparation of yolk@shell composite with other components and structures, offering potential in various applications. Image 1 • Yolk@shell structured Fe 3 O 4 @MnO 2 micrspheres were prepared with the assistance of dopamine through a three-step process. • The prepared Fe 3 O 4 @MnO 2 microspheres show excellent electrochemical performance as supercapacitor electrode. • The assembled ASC of Fe 3 O 4 @MnO 2 //N-pC delivers a high energy density of 31.3 Wh/kg at a power density of 750 W/kg. [ABSTRACT FROM AUTHOR]

The study is aimed at the present challenge in tandem catalysis, addressing how to achieve tandem catalytic ability and meantime to avoid a mutual engagement between the tandem processes. This objective was met by constituting a nanoreactor with bio-inspired compartments made of core-and-shell architectures. The core-and-shell architectures allowed the nanoreactor to spatiotemporally separate the tandem catalytic processes from each other, in virtue of the restriction from mass transfer and the radial distribution of reaction loci. The shell in this nanoreactor admitted a precursor reaction while the core was responsible the following reaction. There was no mutual engagement in the tandem processes, due to the spatiotemporally-driven sequential catalysis in the nanoreactor. In this way, this nanoreactor demonstrated the "undisturbed" tandem catalytic ability. Differing from reported nanoreactors and bi-functional catalysts which often involve a mutual competition and even cross-reactions between the tandem processes, this nanoreactor may partition the tandem catalytic processes and avoid the mutual engagement. The constitution of this nanoreactor suggests a prospect to develop "undisturbed" tandem catalysts for complicated catalytic processes. [ABSTRACT FROM AUTHOR]

This study is aimed at the present challenge in tandem catalysts, addressing how to endow the catalysts with self‐controlled tandem catalytic‐ability. By borrowing the predation strategy from sundew, the objective was originally met by reporting a smart tandem catalyst which can self‐control the tandem catalytic behavior by catching, decomposing and assimilating the engaging molecules (such as 4‐nitrophenyl acetate). This catalyst was made of a unique leaf containing two functional layers where each may be responsible for one coupled process. The first layer in this catalyst was fabricated with a zipper‐like reactive polymer capable of opening and closing, which allowed the catalyst to catch and decompose 4‐nitrophenyl acetate. The second layer in this catalyst allowed, however, further access to assimilate the decomposed substrate (i. e., 4‐nitrophenol), made of an antibody‐like polymer and encapsulated metal nanoparticles. In this way, the use of this catalyst led to the occurrence of the self‐controlled tandem catalytic‐ability. This novel design suggests a new protocol for developing smart tandem catalysts, which opens new opportunities for controlled tandem catalytic processes. Copying Nature: Inspired by the predation strategy in sundews, this study presents the first case of smart tandem catalysts which can self‐control the tandem catalytic behavior by catching, decomposing and assimilating the engaging molecules (such as 4‐nitrophenyl acetate). This catalyst was fabricated with a unique leaf made of two functional layers where each may be responsible for one coupled process. This novel design opens new opportunities for controlled tandem catalytic processes. [ABSTRACT FROM AUTHOR]

This study was aimed at addressing the present challenge in self-controlled catalysts, about how to furnish the catalysts with self-governed catalytic ability in water. This objective was met by constructing a polymer composite reactor inspired from marine mussels, made of an aquatically autonomous polymer and encapsulated metal nanoparticles. The aquatically autonomous properties at the polymer support, in combination with the catalytic ability of metal nanoparticles, allowed the reactor to run catalysis with aquatically ‘autonomous’ access, which led to the occurrence of aquatically self-governed catalytic ability. This reactor showed poor catalytic reactivity in water at relatively low temperatures due to the ‘closed’ polymeric networks, which blocked access to the encapsulated metal nanoparticles. This reactor showed, however, significant reactivity in water at relatively high temperatures in response to the ‘openness’ of the access. Unlike the switchable catalysis at reported catalytic reactors which usually involved conventional hydrophilic/hydrophobic transition and the leaching of metal nanoparticles, the switchable catalysis at this reactor ran naturally with the aquatically autonomous access that did not involve any hydrophilic/hydrophobic transition and the leaching of metal nanoparticles. This protocol suggested opportunities for developing robust smart catalysts for aquatic chemical processes. [ABSTRACT FROM AUTHOR]

The graphene oxide (GO) nanosheets/carboxyl-functionalized multi-walled carbon nanotubes (CNTs) hybrids (GO/CNTs) were synthesized via vacuum filtration solution hybrid dispersion and the corresponding GO/CNTs/polyimide (GO/CNTs/PI) nanocomposite films were facilely prepared by in situ polymerization. Both the thermal stability, mechanical and tribological properties of GO/CNTs/PI nanocomposites were greatly improved compared with those of pure PI due to the homogeneous dispersion of GO/CNTs and the strong interfacial covalent bonds between GO/CNTs and the PI matrix. Furthermore, GO/CNTs/PI nanocomposites exhibited the much lower friction coefficient compared to that of PI composites with the same loading of GO or CNTs only, suggesting the synergistic effects of GO/CNTs hybrids on the tribological properties of polyimide nanocomposites, especially the weight ratio of GO and CNTs was 3:1. [ABSTRACT FROM AUTHOR]

In this work, the molecular imprinted polymers were synthesized with the low monomer concentrations for dibutyl phthalate (DBP). The polymers were prepared over carboxyl-modified silica nanoparticle, which used methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker agent and azoisobutyronitrile as the initiator in the process of preparation. Various measures were used to characterize the structure and morphology in order to get the optimal polymer. The characterization results show that the optimal polymer has suitable features for further adsorption process. And adsorption capacity experiments were evaluated to analyze its adsorption performance, through adsorption isotherms/kinetics, selectivity adsorption and desorption and regeneration experiments. These results showed that the molecular imprinted polymers had a short equilibrium time about 60 min and high stability with 88% after six cycles. Furthermore, the molecular imprinted polymers were successfully applied to remove dibutyl phthalate. The concentration range was 5.0–30.0 μmol L −1 , and the limit of detection was 0.06 μmol L −1 in tap water samples. [ABSTRACT FROM AUTHOR]

A novel porous carbon C-(BA-a) has been simply synthesized from a commercialized benzoxazine resin (BA-a) using a soft-templating method. The chemical structure of BA-a has been confirmed by H nuclear magnetic resonance spectroscopy (NMR) and Fourier transform infrared spectroscopy (FT-IR) and its polymerization behavior is monitored by in situ FT-IR and differential scanning calorimetry (DSC). In order to increase the active site of surface electrochemical reactions and promote the wettability in aqueous electrolyte, a facile chemical surface activation is used on C-(BA-a) by nitric acid. The acid-modified porous carbon, N-C-(BA-a), is applied as the active materials for supercapacitors using NaSO as an eco-friendly electrolyte. After acid treatment, the N-C-(BA-a) exhibits the largest specific capacitance of 99.94 F g at a current density of 0.1 A g in 1 M NaSO electrolyte, which is more than 16 times larger than that of the C-(BA-a). Additionally, the N-C-(BA-a) possesses excellent cycling stability over 5000 cycles, suggesting its potential application for supercapacitors. [ABSTRACT FROM AUTHOR]

Supercapacitors with high power density and excellent cycle life are considered to be a promising energy storage system for electric vehicle application. Because of low cost and high abundant, the preparation of iron oxides-based supercapacitors has become significant. Here, we reported the preparation of magnetite supercapacitors by using a facile one-step solvothermal method, where Mn has been used as the doping element to modify the electrochemical properties of FeO. The simply prepared supercapacitor showed a much higher electrochemical capacitance in contrast to reported FeO-based electrochemical capacitors. The electrochemical capacitance at this supercapacitor can be as high as 268.4 F g when the Mn doped reached 1.5 mmol. There was not significant decrease in the capacitance after recycling 600 at 2 A g in KOH aqueous solution. The excellent properties in the supercapacitor share a promising prospect with the development of a next generation of high- performance energy storage devices. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Magnetic FeO@C nanocomposites with well-defined core@shell structure were synthesized via a facile one-step solvothermal process using ferrocene as both iron and carbon resource in the presence of hydrogen peroxide (HO). The as-prepared FeO@C nanocomposites were employed as adsorbent materials for removal of methylene blue (MB) from aqueous solution. Several experimental parameters, including contact time, acidity of the solution, and initial MB concentration were investigated. The result showed that the equilibrium uptake of MB was related to the MB initial concentration as well as acidity of the solution. The adsorption kinetics of MB was dominated by the pseudo-second order reaction model. Significantly, the synthesized FeO@C nanocomposites could be easily isolated from the adsorption system after adsorbing MB and showed prominent reusability. All results indicated that the prepared FeO@C composites had the potential to be used as adsorbents for the removal of dye pollutant from wastewater. [ABSTRACT FROM AUTHOR]

Preparation of traditional rubbers with excellent self-healing ability is a difficult issue in the field of polymer materials. In the current work, we proposed a new way to fabricate self-healing traditional rubber by blending the polar rubber (epoxidized natural rubber, ENR) with the other polar polymer (polyurethane, PU) containing C C bonds and 2-ureido-4[1H]-pyrimidinone (UPy) groups (PU-UPy). It was demonstrated that the ENR/PU-UPy blend exhibits high self-healing efficiency. During curing, slightly covalent network forms in the blend, which is beneficial for the improvement in the compatibility between the two polymers. Multiple hydrogen bond networks including intermolecular hydrogen bonds between the ENR chains and the PU-UPy chains and strong hydrogen bonds between the UPy groups determine the excellent self-healing ability of the blend. The current blending method provides new ideas for the design of new self-healing traditional elastomers. [Display omitted] • A self-healing traditional rubber composed of the polar rubber and the other polar polymer. • The blend exhibits high self-healing efficiency and excellent mechanical properties. • This method provides new idea for the design of new self-healing elastomers. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we demonstrated the effect of crystal defects on the photoelectrochemical properties of ZnO nanorod arrays (NRAs). Vertically aligned ZnO NRAs with different defect contents were grown on F doped SnO2 (FTO) glass substrate via facile electrochemical process and annealing treatement. [Copyright &y& Elsevier]