Strong Interfacial Interaction Research Articles

Highly stable polyaniline array@ partially reduced graphene oxide hybrid fiber for high-performance flexible supercapacitors

The development of flexible supercapacitors (SCs) with high energy density, excellent deformation and cycling stability has great meaning for flexible electronic. Herein, polyaniline array@carbon nanotubes/partially reduced graphene oxide hybrid fiber (PANI@CNT/PRGO) was rationally designed and fabricated. The PANI array were vertically and uniformly grown on CNT/PRGO fiber by controlling the nucleation sites on the fiber. This unique structure enabled the ion to rapid diffusion and the electron to fast transport and sufficient utilization of active sites. The strong interfacial interaction between PANI and CNT/PRGO fiber can reduce the risk of PANI shedding from the fiber during mechanical deformation and long-term cycling. As a consequence, a fiber-shaped SC fabricated by PANI@CNT/PRGO fiber can deliver high volumetric capacitance of 50.2 F cm−3 at a current density of 60 mA cm−3 with 62.5% capacitance retention at 2000 mA cm−3. More encouragingly, the device not only possesses outstanding flexibility and deformation stability (Retention 96.6% after 2000 bending cycles) but also owns prominent long-term stability (Retention 95.8% after 20,000 cycles). Furthermore, the device can yield an outstanding energy density up to 6.97 mWh cm−3. This findings may carve out a new path for regulating the nucleation sites to control the distribution of nanomaterials on graphene fiber, thus obtain hybrid fiber electrodes with outstanding electrochemical performances.

Mixed matrix composite PEM with super proton conductivity developed from ionic liquid modified silica nanoparticle and polybenzimidazole

Phosphoric acid (PA) leaching, low proton conductivity and weak mechanical strength of the polybenzimidazole (PBI) membrane need to be improved considerably for the development of proton exchange membrane (PEM). We have addressed these issues by preparing a mixed matrix composite (MMC) membrane comprising of oxy-polybenzimidazole (OPBI) and imidazole ionic liquid modified silica (ImILSi). Imidazolium based ionic liquid was synthesized and grafted to the surface of the silica nanoparticles (SiNP) to obtain ImILSi which further blended with OPBI to obtain OPBI@ImILSi. The uniform dispersion nature of the ImILSi in the OPBI matrix and the strong H-bonded interfacial interactions between nanofillers and polymers are found to be primary reason for significant improvement of various physical properties of the MMC. TGA, DMA and stress-strain studies exhibited significant enhancement in the thermal and mechanical properties of the MMC membranes. Most importantly, due to the loading of hydrophilic ImILSi, the MMC membranes resulted higher PA loading (∼3-fold increase) which enabled the formation of facial proton transport nanochannels for their superior proton conduction under anhydrous environment and elevated temperature. For example, the OPBI@ImILSi-3% membrane showed proton conductivity value of 0.219 S cm−1 at 160 °C which is a ∼4-fold increase compared to OPBI membrane.

Regulating solvation structure in gel polymer electrolytes with covalent organic frameworks for lithium metal batteries

Stable and safe Li metal anodes are urgent demands for high-energy-density lithium metal batteries (LMBs). The safety concern of LMBs roots in the intrinsic high reactivity of the solvent sheath with Li metal, and the solvent-oriented fragile solid electrolyte interphase (SEI) causes the continuation of malignant reaction and Li dendrite growth. The SEI composition is closely related to the solvation structure of electrolytes. Furthermore, it is also necessary to alleviate the leakage of liquid electrolytes. Herein, regulating solvation structure by the covalent organic framework (COF) in gel polymer electrolyte (GPE) prepared with a one-step radiation method is proposed to achieve superior cycle performance and leakage-free safety in batteries. The COF with a unique channel structure and abundant lithophilic groups of amino and aldehyde (TpPa-2) exists in strong interfacial interaction with solvated Li + and thus interferes with Li + -solvent coordination. The TpPa-2 modified GPE with increased intimate ion pairs results in the construction of an anion-derived, LiF-rich SEI to regulate Li plating/stripping. The resultant LiFePO 4 (LFP)//Li coin cell demonstrates superior capacity retention (75%, 1000 cycles) at 0.5 C. Furthermore, the assembled LFP//Li pouch cell displays excellent flexibility and the capability of resisting LE leakage. This study demonstrates an effective strategy of offering dependable COF-modified GPE to develop LMBs and provides a new horizon into the character of the COF in the long-term cycle performance of LMBs.

Electron-enriched regulation of sulfur-active site for accelerating atomic hydrogen desorption of S-rich MoWS2+ cocatalyst toward efficient photocatalytic H2 evolution of TiO2

• An electron-rich regulation idea was developed to weaken the strong S-H ads bonds. • The active-sulfur number and efficiency of MoWS 2+ x was simultaneously optimized. • The S-rich MoWS 2+ x was prepared by one-step photoinduced electron-reduction method. • H 2 -evolution rate of TiO 2 can be significantly improved by S-rich MoWS 2+ x . Metal chalcogenides (MS x ) as H 2 -evolution cocatalysts generally suffer from unfavorable H desorption property because of the strong interfacial interaction between the adsorbed H and intensely electronegative S sites (S-H ads , 363 KJ mol −1 ), which seriously hampers the H ads from desorbing to generate free H 2 . Herein, a universal strategy of electron-enriched regulation of sulfur-active site is developed to weaken the strong S-H ads bonds by introducing W heteroatoms into MoS 2+ x to form sulfur-rich MoWS 2+ x bimetal cocatalyst (expressed as MoWS 2+ x ). In this case, the S-enriched MoWS 2+ x is skillfully produced and simultaneously anchored with the TiO 2 by a facile photoinduced electron-reduction method, involving the aforehand formation of homogeneous W(MoS 4 ) x and their subsequent in-situ photoinduced deposition procedure. Photoactivity experiments exhibit that the MoWS 2+ x /TiO 2 (2:1) sample obtains the highest H 2 -evolution rate of 4620.8 μmol h −1 g −1 (AQE = 22.2 %) with a great promotion of 3.6 folds compared to the MoS 2+ x /TiO 2 sample. In situ/ex situ XPS characterizations and density functional theory (DFT) calculations reveal that the integration of W heteroatom into MoS 2+ x can regulate its electron density to form electron-enriched S (2+δ)− sites, thus availably weakening the S-H ads bonds to optimize atomic H desorption and accordingly enhancing the hydrogen-evolution activity of TiO 2 . This study provides a unique idea to optimize the electron densities of activity sites, which is vital for the development of efficient catalytic materials.

Development of strong, tough and flame-retardant phenolic resins by using Acacia mangium tannin-functionalized graphene nanoplatelets

Constructing an eco-friendly phenolic resin with high toughness, strength, and flame retardancy is of great significance and challengeable in the wood-based panels industry. Acacia mangium tannin (AMT), as a biological macromolecule, was decorated onto graphene through ball milling. The formed AMT-functionalized graphene nanoplatelets (AMT@GnPs) were used to replace 40 % phenol to greenly modify and reinforce phenolic resins. The fabricated phenolic resin (BGTPF) exhibited high wet bonding strength of 1.58 MPa, high tensile strength of 24.4 MPa, and large toughness of 0.35 MJ m−3, which were 38.6 %, 27.7 %, and 75.0 % increments compared with the 1.14 MPa, 19.1 MPa and 0.20 MJ m−3 of the neat AMT-modified phenolic resin (TPF). These improvements were attributable to the good compatibility and strong interfacial interactions between AMT@GnPs and the resin matrix, which promoted the transfer and dissipation of load energy. The prepared BGTPF resin showed good flame retardancy and high thermal stability. The peak HRR decreased from 15.5 for TPF to 6.9 W/g for BGTPF. This work presents a new, low-cost, and sustainable strategy to construct mechanically strong, tough, and flame-retardant tannin-based phenolic resins for many promising applications such as engineered wood-based products.

Enhanced Functional Properties of Bioplastic Films Using Lignin Nanoparticles from Oil Palm-Processing Residue.

The development of bioplastic materials that are biobased and/or degradable is commonly presented as an alleviating alternative, offering sustainable and eco-friendly properties over conventional petroleum-derived plastics. However, the hydrophobicity, water barrier, and antimicrobial properties of bioplastics have hindered their utilization in packaging applications. In this study, lignin nanoparticles (LNPs) with a purification process were used in different loadings as enhancements in a Kappaphycus alvarezii matrix to reduce the hydrophilic nature and improve antibacterial properties of the matrix and compared with unpurified LNPs. The influence of the incorporation of LNPs on functional properties of bioplastic films, such as morphology, surface roughness, structure, hydrophobicity, water barrier, antimicrobial, and biodegradability, was studied and found to be remarkably enhanced. Bioplastic film containing 5% purified LNPs showed the optimum enhancement in almost all of the ultimate performances. The enhancement is related to strong interfacial interaction between the LNPs and matrix, resulting in high compatibility of films. Bioplastic films could have additional advantages and provide breakthroughs in packaging materials for a wide range of applications.

Interfacial electronic heterostructure engineering of cobalt boride nanosheets toward broadband efficient electromagnetic absorption

Vigorous reflection loss (RL), wide bandwidth together with suitable absorption frequency band are key application indicators for cutting-edge electromagnetic (EM) absorbers to avoid EM pollution in the aerospace. However, the rational design of EM absorbers, especially for the integration of multiple properties, remains highly challenging. Here, we report a novel two-dimensional (2D) nanosheets-like heterostructure constructed by a molten salt-assisted dissolution-growth strategy and linked via strong interfacial electronic interactions, namely, cobalt boride (CoB) with boron, nitrogen co-doped carbon (CoB/BNC). Density functional theory (DFT) calculations demonstrate that stable heterointerfaces formed by strong interfacial electronic interactions are beneficial for enriching polarization effects, while contributing sufficient dielectric loss to boost the EM absorption (EMA) performance. Accordingly, the minimum RL (RLmin) of −70.76 dB and effective absorption bandwidth (EAB) of 4.72 GHz are simultaneously accomplished for CoB/BNC at the thickness of 3.48 mm. Moreover, radar cross section (RCS) simulation results confirmed that the as-prepared absorber coating could perfectly suppress the metal scattering sources in different directions. Generally, this work offers an ingenious engineering strategy for the precise synthesis of functional heterostructures, which holds great promise for developing innovative EMA materials in the aerospace.

Biomineralized dipeptide self-assembled hydrogel with ultrahigh mechanical strength and osteoinductivity for bone regeneration

Peptide self-assembled hydrogels are ideal scaffolds for three-dimentional cell culture and tissue engineering due to their native extracellular matrix enabling the transport of nutrients as well as the cells growth and expansion. However, the use of peptide hydrogels in the hard tissues regeneration such as alveolar and skull bone has been largely unexplored, hindered by the insufficient mechanical strength and osteogenesis activity. Herein, peptide self-assembled nanostructures are used as templates to emulate natural biomineralization process. The vaterite nanoparticles loaded with thermolysin act as a role of mature osteoblasts secreting collagen fibrils to initiate dipeptide self-assembly as biomimetic extracellular matrix. Meanwhile, the vaterite nanoparticles with a high specific surface area form strong intermolecular and interfacial interaction with hydrogel networks, acting as a cross-linker to achieve extrafibrillar mineralization. Moreover, vaterite nanoparticles function as a mineral reservoir to release Ca2+, inducing intrafibrillar mineralization, further enhancing the mechanical property. The resulting hydrogel exhibits an unprecedently high value of storage modulus (473 kPa), excellent biocompatibility and osteoinductivity. In rat calvarial defect model, the hydrogel significantly accelerates regeneration of osteogenesis tissue, thus indicating the potential of such peptide hydrogels for application in bone regeneration.

Synergistically boosted non-radical catalytic oxidation by encapsulating Fe3O4 nanocluster into hollow multi-porous carbon octahedra with emphasise on interfacial engineering

Investigating the mechanisms of interfacial processes of supported metal catalysts is crucial for advanced oxidation processes (AOPs) of peroxymonosulfate (PMS) activation on efficient water remediation. In this research, we have successfully synthesized an exclusive nanocarbon catalyst encapsulating Fe3O4 nanoparticles in hollow multi-porous structures (termed ‘H-Fe3O4@C') as a catalyst for activating PMS towards the degradation of bisphenol-A (BPA). Superior catalytic performance of H-Fe3O4@C was observed as BPA was completely degraded within 40 min. This observation ascribed to stronger interfacial interactions between the Fe and C layer, which could be attributed to the presence of multiple Fe-C bonding that allows for electron tunnelling to the adjacent carbons than Fe3O4. The results of density functional theory calculations show that the Fe3O4 active center encapsulated in the center of the carbon framework can regulate the adsorption tenderness of carbon materials, resulting in excellent interfacial interaction provided optimal active sites with low adsorption energy(−1.31 eV) and long O-O bond(dO-O = 1.592 Å). Electrochemical analysis conceded that the atomic interfacial bonds (Fe-C) promoted electronic communication between surfaces. At the same time, the vacuum packaging structure enhances the stability of the catalyst and prevents the continuous leaching of active metals. The dissolved iron concentration after the reaction of H-Fe3O4@C was only 3.37% of that of bare Fe3O4 (14.6 mg L−1). Overall, this research sheds a new insights on the critical role of strong interfacial interactions in non-radical activation of PMS.

Hydrothermal preparation of MoX2 (X = S, Se, Te)/TaS2 hybrid materials on carbon cloth as efficient electrocatalyst for hydrogen evolution reaction

The prominent features-based two-dimensional (2D) materials have proven themselves as efficient as well as robust electrocatalysts for the hydrogen evolution reaction (HER) owing to their low-cost, abundance and predominant conductivity. In this work, we report the synthesis of series of molybdenum chalcogenide nanostructures MoX2 (X = S, Se, Te), hybridized with TaS2 nanosheets, via a facile hydrothermal method, on self-supported carbon cloth electrode. Used as an electrocatalyst for HER, hybrid phase MoSe2/TaS2/CC electrode with a Mo/Se ratio of 1:1.5 exhibits the best HER performance, which could afford the benchmark current densities of 10 mA/cm2 at the overpotentials of 75 mV with the measured Tafel slope values of 54.7 mV/dec. In addition, the presented molybdenum dichalcogenides in this work are also complimented with robustness as determined from durability and air stability measurements. The unique aspects of these unique hybrids, such as 1T and 2H phases hybridized MoS2 and MoSe2, semimetallic nature 1T′-MoTe2 petal clusters and strong interface interaction between MoX2 (X = S, Se, Te) and conductive TaS2 nanosheets, cause superior HER catalytic performance.

Flexible and hydrophobic nanofiber composites with self-enhanced interfacial adhesion for high performance strain sensing and body motion detection

Flexible and electrically conductive fibric (fiber) composite (CFC) strain sensors are promising in smart wearable electronics. Challenges remain to develop CFC with strong interfacial interaction and excellent durability. Here, a facile and cost-efficient method is proposed to fabricate flexible and hydrophobic CFCs with self-enhanced interfacial adhesion based on ultrasonication induced carbon black nanoparticles (CBNPs) embedded onto the swelled polyurethane (PU) nanofiber membranes immersed in a mixed solvent. CBNPs were tightly decorated onto the nanofiber surface, while the electrical conductivity keeps stable during cyclic durability tests. The CBNPs improve the Young’s modulus and tensile strength while maintain the outstanding stretchability of PU membrane. The CBNPs also endow the CFCs with hydrophobicity and photo-thermal conversion property. The stretchable CFC strain sensors show controllable sensitivity and cyclic stability, and can monitor various body motions. This work provides a new route to fabricate low-cost and high-performance strain sensors without using interfacial bonding agents.

Tea‐polyphenols mediated interfacial modifier to integrate reinforcement, reprocessability, and shape memory properties into rubber/carbon black composites via coordination bonds

AbstractCarbon blacks are important fillers to reinforce, functionalize rubber materials and reduce their prices. However, environment‐friendly surface modification of carbon blacks is not trivial to conduct, yet challenging to effectively sever broad rubber galleries. Inspired by wet adhesion of mussel, tea polyphenols (TPs) are coated on carbon blacks by vacuum absorption method (i.e., TP@C) and then they are mixed into nitrile butadiene rubber with ZnCl2. Specially, Zn2+/TP@C coordination interfaces are formed together with crosslinking structures of Zn2+‐CN of NBR after hot pressing. As a sequence, the rubber composites achieve superior strength and modulus reinforcement owing to strong interface interactions and good dispersion of TP@Cs. Reversible coordination crosslinking network and TP@C network topology can be rearranged at elevated temperatures, endowing the composite good plasticity and reprocessablity. Furthermore, the composites possess stable shape memory properties for five cycles and good plasticity based shape memory ability, showing great advantages in application potential of smart material fields.

Strong interfacial interactions of ZnS/Cu-TCPP hybrids contribute to excellent nonlinear optical absorption

In recent years, the research and development of optoelectronic devices based on metal-organic frameworks (MOFs) have increasingly triggered the interest and attention of researchers. However, their nonlinear optical (NLO) properties are in urgent need of improvement. Herein, we first report a method to improve the NLO response of MOFs by decorating ZnS nanoparticles. The NLO response of the hybrid is found to be much higher than that of pure MOFs and ZnS by the Z-scan technique. At higher incident intensities, the hybrids exhibit a giant optical limiting (OL) response with OL threshold as low as 2.82 × 10−7 J/cm2, which is better than almost all organic and inorganic materials reported in the literature so far, demonstrating the great value of hybrids for OL devices. As revealed by XPS characterizations, transient absorption (TA) spectroscopy, and DFT calculations, the strong interfacial interaction between ZnS nanodots and Cu-TCPP nanosheets can effectively promote the charge transfer process between them and significantly inhibit the recombination of photogenerated charge carriers, thus achieving a substantial enhancement of the NLO response. The simple preparation method and extremely low OL threshold suggest that this MOF-based hybrids have great potential for application in OL photonic devices.

In-situ polymerization of polycarbazole-zinc oxide nanocomposite: An in silico docking model and in vitro antibacterial biomaterial

The current study focuses on the synthesis of polycarbazole-zinc oxide (PCz/ZnO) nanocomposite and its application as an in vitro antibacterial biomaterial as well as an in silico docking model. The synthesized pristine polymer, polycarbazole (PCz) and its nanocomposite PCz/ZnO were characterized by Fourier transform infrared (FT-IR), Thermo-gravimetry/Differential Thermo-gravimetry (TG-DTG), X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Brunauer-Emmett-Teller (BET), Energy-dispersive X-ray (EDX), Raman and X-ray photoelectron spectroscopic (XPS) techniques. FT-IR, XRD, FE-SEM, and XPS studies revealed that the polymerization of Cz has been successfully achieved on the surfaces of ZnO nanoparticles, indicating the strong interfacial interaction between PCz and ZnO nanoparticles. However, TG-DTG studies revealed that the nanocomposite, PCz/ZnO, proved thermally more stable compared to the pristine polymer, PCz. Further, the pristine PCz and PCz/ZnO nanocomposite were evaluated for antibacterial activity against Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. The nanocomposite PCz/ZnO showed the highest zone of inhibition against K. Pneumoniae (17 mm), followed by P. aeruginosa (16 mm), then S. aureus (14 mm) and E. coli (19 mm) at 80 mg ml−1. Significantly, the in silico molecular docking predicts the modes of interactions of PCz and PCz/ZnO with B-DNA. Briefly, the results obtained from in silico molecular docking studies of the pristine PCz and PCz/ZnO nanocomposite with negative free binding energies (-7.1 kcal mol−1 of PCz and −6.23 kcal mol−1 of PCz/ZnO) imply an excellent and favourable binding affinity vis-à-vis interaction modes of both pristine PCz and PCz/ZnO nanocomposite (drugs) with B-DNA bases (target).

Nanocatalysts induced self-triggering leather skin for human–machine interaction

Electronic skins mimicking the comprehensive functions of human skin are highly interesting for the development of human–machine interactions (HMI). Conventional conductive leathers face challenges of the non-uniform dispersion of conductive components and the complicated fabrication processes, hindering their applications for electronic skins. Herein, a novel ionically conductive leather skin is developed by in-situ self-triggering gelation of ionogel in the hierarchical structure of leather matrix. The core–shell structured liquid metal@catechin nanocatalysts enable rapid and uniform gelation within tens of seconds under ambient conditions. Resulting interpenetrating ionogel networks within leather matrix not only provide 3D continuous and highly conductive pathways for ionic transport, but also form multiple bonding for strong interfacial interactions. These advantageous properties endow leather skin with excellent mechanical robustness (tensile stress:17.8 MPa; toughness: 1590 kJ/m3), high air transmission rate (720 mL/cm2/h) and water vapor transmission rate (70 g/m2/h), as well as broad environmental tolerance (-80 ∼ 100 °C). Impressively, the leather skin-based sensors exhibit stable and fast response with only 40 ms. The attractive performances of leather skin are further demonstrated by a bionic glove as a gesture-discernible wearable controller for HMI. This work opens up a new horizon for developing the ionically conductive leather skin, which will have profound implications for wearable electronic systems.

Adaptable thermal conductive, high toughness and compliant Poly(dimethylsiloxane) elastomer composites based on interfacial coordination bonds

Compliant elastomers have been widely used in industry and daily life benefited from their large reversible deformability. But poor thermal conductivity and toughness of unfilled elastomers usually limit their use in thermal management. The most common method to increase these properties is to incorporate thermally conductive fillers to polymeric materials. However, thermally conductive network formed by the large of fillers not only decreases the elastomeric compliance, but may also damages the toughness. Herein, to study the effect of polymer/filler interfacial interaction on thermal and mechanical properties, we choose shorter poly(dimethylsiloxane) without entanglement to construct elastomer composites by non-covalent interfacial carboxyl/aluminum and carboxyl/zinc oxide coordination bonds. Time-domain thermoreflectance technique demonstrates that the strong interfacial interaction leads to reduced interfacial thermal resistance between polymeric materials and fillers, resulting in enhanced thermal conductivity of the elastomer composites. Otherwise, two independent dynamic coordination bonds have been investigated on temperature- and frequency-sweep rheometer. The results reveal that the elastomer composites can counteract the negative effect of high filler content on toughness and compliance according to energy-dissipation of dissociation and generation of dynamic coordination bonds. Thanks to the enhanced interfacial interaction, our material shows high toughness (1073 J/m2), thermally conductive (2.37 W/(m·K)), compliant (stress is 0.11 MPa and elongation break is 910%) and fully reprocess. For the application as thermal interface materials, we demonstrate effective heat dissipation on chip and LED. Our present work suggests that the design principles based on interfacial coordination interaction can be applied to the development of new classes of elastomer composites.

Effects of carboxymethyl chitosan-assisted dispersion of silica on interface and mechanical properties of rubber composites

Uniform distribution of fillers and strong adhesion at the rubber-filler interface are two pivotal factors to fully utilize the special properties of nanofillers to strengthen rubber. Unfortunately, there are generous hydrogen-bond interactions between SiO2 nanoparticles because of the abundant active hydroxyl groups on their surfaces, contributing to the existence of a large number of SiO2 agglomerates in rubber matrix and the difficulty in forming strong interfacial interactions between SiO2 and rubber. In this study, carboxymethyl chitosan (CMCS) was used to assist the dispersion of SiO2 in carboxylic styrene butadiene rubber (XSBR) to prepare high-performance rubber composites via latex film-formation. Latex blending film-formation is a unique processing method that could maintain the original self-assembly structure of filler particles during film-formation to the greatest extent. The results revealed that the hydrogen bond formed between CMCS and SiO2 strikingly promoted a better dispersion and distribution of SiO2 in the XSBR matrix and enhanced the rubber-filler interfacial interactions. The tensile strength of XSBR/20 wt% SiO2 composite with CMCS was about 122 % higher than that of the composites without CMCS. Furthermore, based on the non-covalent interactions between the active groups of XSBR/CMCS/SiO2 composites and inorganic substrates, the composites could form strong adhesion to inorganic substrates.

Development of interfacial strong Interaction-enhanced C-F@CuBi2(Ox/N1-x)4/CN Nano-sheet clusters photocatalysts for the simultaneous degradation of tetracycline and reduced Cr(VI)

Antibiotics and heavy metal contaminants often co-exist in wastewater, but developing photocatalysts that can remove them simultaneously without secondary contamination and with easy recovery remains a huge challenge. Regrettably, conventional nano-photocatalysts have the inherent disadvantages of high reflectance of sunlight and high electron and hole recombination rates, and more importantly, nanoparticles dispersed in water cannot be efficiently recovered. Herein, we report a p-n heterojunction photocatalyst formed by growing CuBi2(Ox/N1-x)4 (CBON) nano-sheets clusters directly on copper foam (CF) surfaces and introducing N-doped carbon material (CN) on CBON. Such unique nanostructures not only allows visible light to be reflected many times internally, which helps to improve the absorption of visible light, but also provides many active sites for photocatalytic processes and the rapid separation of electrons from holes. The CF@CBON/CN enables simultaneous degradation of tetracycline and reduction of Cr(VI) (97.1% and 98.9% respectively). Moreover, the method of growing CBON/CN nano-sheet clusters on CF overcomes a number of problems (increased interfacial charge transfer impedance, poor structural stability and non-uniform distribution, etc.) associated with conventional methods of combining nanomaterials with recyclable substrates (loading, introduction of adhesives and hybridization, etc.). The Rct of CF@CBON/CN approximate 30 ohms, greatly smaller than conventional powder materials. More than 10 cycles can be achieved without any physical recovery and restoration work. DFT analysis shows that the strong interfacial interaction enhances the conductivity and electron transfer efficiency of the nitrogen-doped heterojunction structure. In addition, we built a simulated photocatalytic filtration unit which achieved efficient degradation of TC and reduction of Cr(VI) (92.8% and 95.1% respectively).

Suppressed Layered-to-Spinel Phase Transition in δ-MnO2 via van der Waals Interaction for Highly Stable Zn/MnO2 Batteries.

Although birnessite-type manganese dioxide (δ-MnO2 ) with a large interlayer spacing (≈7 Å) is a promising cathode candidate for aqueous Zn/MnO2 batteries, the poor structural stability associated with Zn2+ intercalation/deintercalation limits its further practical application. Herein, δ-MnO2 ultrathin nanosheets are coupled with reduced graphene oxide (rGO) via van der Waals (vdW) self-assembly in a vacuum freeze-drying process. It is interesting to find that the presence of vdW interaction between δ-MnO2 and rGO can effectively suppress the layered-to-spinel phase transition in δ-MnO2 during cycling. As a result, the coupled δ-MnO2 /rGO hybrid cathode with a sandwich-like heterostructure exhibits remarkable cycle performance with 80.1% capacity retained after 3000 cycles at 2.0 A g-1 . The first principle calculations demonstrate that the strong interfacial interaction between δ-MnO2 and rGO results in improved electron transfer and strengthened layered structure for δ-MnO2 . This work establishes a viable strategy to mitigate the adverse layered-to-spinel phase transition in layered manganese oxide in aqueous energy storage systems.

Extremely high energy density and long fatigue life of nano-silica/polymethylvinylsiloxane dielectric elastomer generator by interfacial design

Dielectric elastomer generator (DEG) can harvest electrical energy from various movement in nature such as human walking and ocean waves. To achieve high energy harvesting performance of DEG, dielectric elastomer (DE) composite with strong interfacial interaction, and thus high electrical breakdown strength (Eb) and long fatigue life (NFL) at high strain is a key. In this study, nano-silica (SiO2)/polymethylvinylsiloxane (PMVS) DE composite with strong interfacial interaction for DEG with extremely high energy density (w), high power conversion efficiency (PCE) and long NFL was prepared by designing and synthesizing a new polar macromolecule coupling agent (MCA), ester group grafted liquid butadiene rubber using a photoinitiated thiol-ene click reaction. Compared with the common small molecule coupling agent (SCA) modified SiO2 (SCA@SiO2)/PMVS composite, the new MCA modified SiO2 (MCA@SiO2)/PMVS composite shows much stronger interfacial interaction owing to the largely increased co-crosslinking junction and chain entanglement, resulting in the significantly improved elongation at break and Eb at high strain (400%). As a result, MCA@SiO2/PMVS DEG exhibits an up-to-date highest w (92.2 mJ/cm3) and PCE (35.8%) among the previously reported DEG using unprestretched DE film, and its NFL reaches 141000 times, 3.9 times that of SCA@SiO2/PMVS DEG (36000 times). Thus, MCA@SiO2/PMVS DEG shows the highest full-life generating energy density (9710 J/cm3), 4.8 times and 2427 times that of SCA@SiO2/PMVS DEG and commercial VHB DEG, respectively.