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Polymer‐based thermal interface materials (TIMs) with excellent thermal conductivity and heat dissipation capabilities play a crucial role in addressing the issue of heat accumulation in advanced integrated electronics. However, establishing improved surface interactions and complete networks to enhance efficient phonon transfer remains a significant challenge. To tackle this problem, surface modification and ice‐templating techniques are commonly employed to create the robust interface crosslinks and continuously thermal conductive pathways. Herein, 2‐mercaptobenzimidazole (MB) was used as a reducing and modifying agent to functionalize graphene oxide (rGO‐MB) within the three‐dimensional networks, which was prepared using a combination of hydrothermal and ice‐templating methods. As a result, the reduced graphene oxide/natural rubber (rGO‐MB/NR) TIMs exhibited a remarkable through‐plane thermal conductivity of 0.93 W m−1 K−1 with a filler loading of 3 wt%. The enhanced interface interactions between rGO‐MB and NR, combined with the establishment of a three‐dimensional network, significantly contributed to the improved thermal conductivity and heat dissipation capabilities. Moreover, the obtained TIMs demonstrated favorable mechanical properties (5.06 MPa, 502%) and excellent insulation performance (3 × 1013 Ω cm). These findings provide the valuable insights into potential solutions for mitigating heat accumulation issues in next‐generation electronics. Highlights: rGO‐MB with thiol groups was obtained by the hydrothermal method.Interactions between rGO‐MB and NR mainly depended on the chemical bonds.rGO‐MB/NR TIMs owned the improved thermal management performance. [ABSTRACT FROM AUTHOR]

The development of high‐performance green rubber materials with excellent comprehensive properties is very important for the environment and resources. Graphene has excellent electrical, mechanical, and thermal properties and is regarded as the most promising functional filler for rubber composites. In this work, a facile and efficient strategy was used to prepare graphene rubber materials with balanced integrated properties by chemical modification of graphene oxide (GO) with gelatin (Gel). Gel molecules as bridges could not only connect with GO by chemical bonds, but also physically entangle with natural rubber (NR) molecules. The optimized dispersibility of GO and the enhanced interfacial interaction between GO and NR together enable graphene rubber to exhibit excellent integrated properties, such as tensile strength of 29.7 MPa and heat build‐up of 1.9°C only at 1 phr of Gel‐rGO (G‐rGO) content. Additionally, finite element simulation was used to evaluate the temperature field distribution of graphene rubber tires, and the temperature of the NR/Gel‐rGO (NR/G‐rGO) tread was 17.3°C lower than that of NR/GO. This work will provide effective strategies for the preparation of high‐performance graphene rubber materials. [ABSTRACT FROM AUTHOR]

Owing to its remarkable electrical, mechanical and thermal properties, graphene has been considered the most promising reinforcing filler for the development of rubber nanocomposites. In this work, a novel interfacial structure consisting of reduced graphene oxide (rGO)/N-tert-butyl-2-benzothiazole sulfonamide (NS)/natural rubber (NR) (NR/NS-rGO) with covalent bond connections was fabricated using one-step modification and coprecipitation methods. When the filler loading of NS-rGO is 0.42 vol.%, not only the thermal conductivity of the rubber composite increases to 0.237 Wm−1 K−1, which is 21.5% higher than that of pure NR; meanwhile, the internal heat generation decreases to 2.6 °C, which is 45.8% lower than that of reduced graphene oxide (rGO)/ascorbic acid (VC)/natural rubber (NR) (NR/VC-rGO), and the mechanical properties have been greatly improved. The results demonstrated that the covalent bond connections greatly reduced interfacial thermal resistance at the filler/matrix interface. Furthermore, the enhanced interfacial interaction reduced frictional heat generation at the filler/matrix interface. More importantly, this strategy provided creative insights into the high application potential of graphene in the rubber industry. [ABSTRACT FROM AUTHOR]

A composite RGO/ZnO-mrs, which is reduced graphene oxide (RGO) decorated with ZnO microrods (ZnO-mrs), with excellent electromagnetic wave absorbing performance was prepared by a simple mechanical mixing and direct freeze-drying method. The load of ZnO-mrs in this composite is controlled effectively by changing mass ratio of raw materials Zn(Ac)2·2H2O and graphene oxide (GO), then the balance between dielectric loss ability to electromagnetic wave and impedance matching with free space of the absorbing composite RGO/ZnO-mrs prepared can be obtained, and then its high-performance electromagnetic wave absorption ability. When mass ratio of GO to Zn(Ac)2·2H2O is 1:3, composite RGO/ZnO-mrs filled with only 15 wt% exhibits the most significant electromagnetic wave absorption properties, its minimum reflection loss (RLmin) value of − 38.5 dB is obtained at 15.4 GHz and effective absorption bandwidth (EAB) is up to 5.4 GHz (12.6–18 GHz) with a thickness of 2 mm only. The basic electromagnetic wave absorption mechanism of this composite is discussed systematically. All results demonstrate that composite RGO/ZnO-mrs in this study is very promising as a broadband absorption, light weight, especially with a simple and expandable preparing process electromagnetic wave absorber. [ABSTRACT FROM AUTHOR]

An efficient adsorbent for the treatment of Cr(VI) was simply fabricated by combining graphene oxide with MoS2 nanosheets via in situ hydrothermal process with CTAB as the surfactant. The experimental results indicated that the agglomeration of the MoS2 nanosheets are reduced and uniformly grown on the graphene sheet during the in situ hydrothermal process, and the introduction of graphene oxide provided higher specific surface area and abundant oxygenic groups. Based on this, the removal efficiency of Cr(VI) onto MoS2/rGO was 75.9% at pH 2.0, which was higher than that of bulk MoS2 (61.0%). On account of Sips adsorption isotherm model, the highest uptake capacity of MoS2/rGO toward Cr(VI) reached 80.8 mg g−1. The adsorption kinetic consequences showed that the chemisorption process was the control step, and the removal mechanism for Cr(VI) is redox and adsorption; in this way, the adsorbed Cr(VI) was partially reduced to Cr(III). Furthermore, this as-prepared adsorbent also presented satisfying reusability for removal of Cr(VI) and can be used for the selective removal of Cr(VI) in the presence of NO3−. In short, it may provide a potential route to enhance the adsorption property of MoS2 toward heavy metals through incorporating with GO, which would expand the applications of MoS2 in the field of treatment of the heavy metal wastewater. [ABSTRACT FROM AUTHOR]

• Covalent loading method of cobalt phthalocyanine (CoAlPc) onto graphene oxide (GO). • A small amount of CoAlPc/GO could make phenol mineralized completely under visible light. • CoAlPc/GO shows better photocatalytic activity than CoAlPc-PGMA/SiO 2. • The possible mechanism of photocatalytic degradation of phenol by CoAlPc/GO was proposed. • The photodegradation rate of 20 mg/L of phenol reaches 100% for 5 min with 0.01 g of CoAlPc/GO. In this study, 4-(4-aldehyde-phenoxy) phthalo nitrile (AlPPN) was firstly synthesized from the reaction between nitro groups of 4-nitrophthalonitrile and hydroxyl groups of p‑hydroxy benzaldehyde, and then 4-β-(4-aldehyde-phenoxy)cobalt phthalocyanine (CoAlPc) was prepared by means of the reaction between AlPPN and cobalt chloride catalyzed by DBU. Finally, CoAlPc was covalently immobilized onto amino-modified GO surface via the Schiff-base reaction to prepare CoAlPc/GO hybrids. Their structure and morphology were characterized by FT-IR, TEM, XRD and UV–Vis absorption spectra. These samples are tested for photocatalytic degradation of phenol under visible light irradiation. The loading of CoAlPc on support materials is to the benefit of its photocatalytic activity, and the photocatalytic activity of CoAlPc supporting on GO is higher than that on polyglycidyl methacrylate-modified silica (PGMA/SiO 2). The dosage of CoAlPc/GO has significant effects on the photocatalytic degradation of phenol under visible light irradiation. A low dosage (0.2 g/L) of CoAlPc/GO exhibits the best photoactivity, whose degradation rate for phenol achieves 100% for 5 min and the intermediate (o-benzoquinone) mineralizes completely for 1 h in the presence of H 2 O 2 under visible light irradiation. CoAlPc/GO still has stable photocatalytic activity after repeated use for 7 times. [ABSTRACT FROM AUTHOR]

ZrO2 nanoparticles were electrostatic self-assembled on the surface of graphene oxide (GO) for enhancing the mechanical and tribological properties of phenolic resin. Zeta potential analysis and structural characterization confirmed that ZrO2 nanoparticles had been successfully adhered onto the surface of GO, and the as-prepared ZrO2@GO nanohybrid possessed good dispersity. The results showed that filling 1.5 wt% ZrO2@GO nanohybrid could improve the flexural strength, flexural modulus and impact strength of phenolic resin (PF) by 38.6%, 10.7% and 8.3%, respectively. When 0.5 wt% ZrO2@GO was added, the initial decomposition temperature and the residual content at 800 °C of PF increased by 20.0% and 16.9%, respectively. The ZrO2@GO nanohybrid also exhibited synergistic effect for improving the tribological performance of PF effectively, that when adding 0.5 wt% ZrO2@GO nanohybrid, the average friction coefficient and wear rate of the composites reduced by 21.8% and 30.6%, respectively. SEM observation and 3D non-contact surface topography analysis showed the wear surface of ZrO2@GO nanohybrid filling PF composite was smooth, low spalling and shallowly grooved with the typical characteristic of abrasive wear. It was explained that the ZrO2@GO nanohybrid could play the role of rolling bearings, form stable and smooth friction transfer film and enhance the interfacial interaction, thus indicated the synergistic wear-resisting performance for PF matrix. It provides a green, convenient and fast method for preparing ZrO2 nanoparticles-attached GO nanohybrid that can enhance the mechanical and tribological performance of resin-based materials effectively. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (RGO)/Ni composites with high-performance microwave absorption were successfully synthesized through the electroless plating. The structures and morphologies of the materials were characterized by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy as well as scanning electron microscope. Results show that spherical pure nickel particles are uniformly distributed on the surface of RGO. The complex permittivity and permeability of the composite were measured by mixing RGO/Ni with paraffin, the minimum reflection loss could reach − 51.1 dB, and from 7.28 to 11.28 GHz, the reflection loss is less than − 10 dB. Through the analysis of the absorbing mechanisms, it is found that the quarter wavelength theory contributes more to the absorbing performance than the impedance matching. In addition, changing the electroless plating time is a feasible method to adjust the absorbing properties of the materials. RGO/Ni is an excellent microwave absorption material with a strong tunable absorbing property at its own low content. [ABSTRACT FROM AUTHOR]

The Fe3O4/PANI rod/rGO nanocomposites were prepared by a new synthesis process, and their microwave absorbing properties were further evaluated. Taking advantage of the synergistic effects of the different components in the nanocomposites and the merits of the proposed synthesis strategies, the Fe3O4/PANI rod/rGO nanocomposites showed excellent microwave absorption performance, especially for obtaining giant absorption bandwidth (ca. 14.6 GHz, <− 10 dB). The work does not only confirm the formation of Fe3O4/PANI rod/rGO nanocomposites with wide absorption frequency range, strong absorption property and lightweight, but also provide a new synthesis process of electromagnetic wave absorbents for large-scale production. [ABSTRACT FROM AUTHOR]

In this study, ferrocobalt magnetic nanoparticle decorated reduced graphene oxide (FeCo@rGO)/ultrahigh molecular weight polyethylene (UHMWPE) nanocomposites with good electromagnetic interference (EMI) shielding performance were fabricated via coprecipitation and a subsequent compression molding strategy. The FeCo-decorated rGO (FeCo@rGO) with tailorable magnetic and conductive properties was deposited on the surface of UHMWPE grains. Then, the composite grains were hot compressed to form a segregated 3D FeCo@rGO network in UHMWPE the matrix. This well-formed 3D magnetic and conductive FeCo@rGO network with selective distribution can provide the UHMWPE composite with tunable electrical and magnetic properties. Owning to the multiple reflections of microwaves among the FeCo@rGO conductive network and the magnetic loss induced by the FeCo magnetic nanoparticles, the FeCo@rGO/UHMWPE nanocomposites showed a good EMI shielding effectiveness of 21.8 dB in the X-band with the presence of only 8.97 vol% FeCo@rGO. This method offers an effective strategy to design EMI shielding materials with regulatable conductive and magnetic performance. [ABSTRACT FROM AUTHOR]

The rapid development of electronic information technology makes it more urgent that explore high-efficiency microwave absorption materials to cope with the challenges of electromagnetic pollution for guarding information security and human health. Herein, we prepared functional composites with both broadband microwave absorption and excellent mechanical properties via constructing three-dimensional (3D) reduced graphene oxide (RGO) networks. In these composites, glass fibers (GFs) were uniformly coated by RGO through a straightforwardly feasible repeated dip-coating process and subsequent reduction, which were named (RGO) n @GF (n was dip-coating times). The GFs supported RGO to form 3D networks, which increased the transmission paths and multiple scattering of electromagnetic waves. Meanwhile, the networks improved the electrical conductivity and conduction loss. The results show that the (RGO) 10 @GF reinforced epoxy resin (EP) composites ((RGO) 10 @GF/EP) have particularly significant improvement in microwave absorption properties, achieving a broad effective absorption bandwidth of 7.54 GHz and a low reflection loss of −46.02 dB. Compared with GF/EP, the bending strength and modulus of (RGO) 10 @GF/EP increased by 39% and 45%, respectively. The present work provides an effective solution for developing advanced composites with both broadband absorption and excellent mechanical properties. [Display omitted] • 3D reduced graphene oxide networks are established in glass fiber/epoxy resin composites in a feasible and sample way. • The obtained composites exhibit both broadband microwave absorption performance and excellent mechanical properties. • The effective absorption bandwidth of obtained composites can reach 7.54 GHz with a thickness of only 2.7 mm. [ABSTRACT FROM AUTHOR]

The reduced graphene oxide reinforced silicone-acrylate resin composite films (rGO/SAR composite films) were prepared by in situ synthesis method. The structure of rGO/SAR composite films was characterized by Raman spectrum, atomic force microscope, scanning electron microscopy, and thermogravimetric analyzer. The results showed that the rGO were uniformly dispersed in silicone-acrylate resin matrix. Furthermore, the effect of rGO loading on mechanical properties of composite films was investigated by bulge test. A significant enhancement (ca. 290% and 320%) in Young’s modulus and yield stress was obtained by adding the rGO to silicone-acrylate resin. At the same time, the adhesive energy between the composite films and metal substrate was also improved to be about 200%. Moreover, the erosion resistance of the composite films was also investigated as function of rGO loading. The rGO had great effect on the erosion resistance of the composite films, in which the Rcorr (ca. 0.8 mm/year) of composite film was far lower than that (28.7 mm/year) of pure silicone-acrylate resin film. Thus, this approach provides a novel route to investigate mechanical stability of polymer composite films and improve erosion resistance of polymer coating, which are very important to be used in mechanical-corrosion coupling environments. [ABSTRACT FROM AUTHOR]

A logically reversible Feynman gate was successfully realized under enzyme-free conditions by integrating graphene oxide and DNA for the first time. The gate has a one-to-one mapping function to identify inputs from the corresponding outputs. This type of reversible logic gate may have great potential applications in information processing and biosensing systems. [ABSTRACT FROM AUTHOR]

Highlights Carbon black (CB) with different structural parameters together with graphene oxide were formed into uniformly dispersed filler network for enhancing the abrasion resistance of natural rubber/cis‐1,4‐polybutadiene rubber/trans‐1,4‐poly(isoprene‐butadiene) rubber blended composites. It showed that the CB structural parameters, such as specific surface area, surface activity and structural degree affected the formation of bound rubber. With the increase of bound rubber content, the homogeneity of filler network structure was improved and the filler‐rubber interaction was enhanced, resulting in a remarkable increase in the mechanical properties, thermal performance and abrasion resistance of the composites. Among the different types of CB, the composites filled with high‐structural‐degree CB of N134 had DIN wear volume as low as 76 mm3 and exhibited 19.5% higher abrasion resistance than N330. Wear surface observations and wear mechanism analyses showed that the increase in abrasion resistance was related to the improvement in tear resistance, hardness and thermal properties of the composites. Multiple linear regression analyses yielded that the structural degree in the structural parameters of CB had a significant correlation effect on the formation of bound rubber, and there was a strong linear relationship between the abrasion resistance of the composites and the content of bound rubber. Trans‐1,4‐poly(isoprene‐butadiene) rubber as compatibilizer for NR/BR blends. Synergistic enhancement of rubber using carbon black and graphene oxide. Carbon black with high structural degree promotes the formation of bound rubber. Described correlation between CB structural parameters and abrasion resistance of rubber. [ABSTRACT FROM AUTHOR]

[Display omitted] Electromagnetic wave absorption materials (EWAMs) have become an effective means to address electromagnetic (EM) radiation and enhance stealth technology, among which aerogels are valued for their lightweight nature and excellent designability. This study utilized environmentally friendly preparation and in-situ reduction techniques to fabricate bacterial cellulose (BC) / reduced graphene oxide (RGO) aerogels, achieving tailored EM wave loss capabilities by controlling the reduction time of ascorbic acid. Benefitting from the effects of freeze-casting, BC winding, hydrogen bond, and RGO layers coupling, the aerogel maintains their original structure after reduction and exhibits satisfactory EM wave absorption. The minimum reflection loss (RL min) is −38.52 dB, with an effective absorption bandwidth (EAB) of 6.68 GHz and a maximum radar cross section (RCS) reduction of 44.69 dBsm. Additionally, the aerogel's lightweight (a low density of 9.03 mg/cm3) and outstanding thermal insulation properties enable it to adapt to complex conditions. Thus, the study provides a novel approach for the construction of industrialized and sustainable RGO-based EWAMs. [ABSTRACT FROM AUTHOR]

It is still a bottleneck to simultaneously attain enhanced mechanical properties, thermal conductivity and low heat build-up properties for graphene-rubber composites obtained by conventional fabrication processes. The critical elements to enhance the comprehensive performance of rubber include excellent dispersion and the interaction of filler and matrix. In this work, the increased filler structure degree with point-surface structured SiC/GO (SG) and the strong interface modified with nano-sulfur synergistically improve the dispersibility and interfacial interaction, which effectively achieves excellent integrated performance at low filler content. More importantly, nano-sulfur not only acts as a modifier to improve interfacial compatibility, but also has a vulcanization function that enables SG and natural rubber (NR) molecular chains to form a uniformly distributed cross-linked network structure. Consequently, only when 4 phr of SiC/GO-S (SG-S) filler was added to NR, the tensile strength, thermal conductivity and low heat generation properties are higher than those of NR/GO rubber by 22.5%, 21.2% and 8.3%. Therefore, this work may open new horizons for the development of green tire. [ABSTRACT FROM AUTHOR]

Natural rubber (NR) and butadiene rubber (BR) composites are frequently used in manufacturing tires and conveyor belts, which are susceptible to severe wear, leading to product failure and significant losses. To enhance the wear resistance of NR/BR composites, we prepared NR/BR composites reinforced with a synergy of N-cyclohexylbenzothiazole-2-sulfonamide surface one-step modified reduced graphene oxide (CZ-rGO) and carbon black N234 (CB) using a latex co-precipitation method. This study explored the effects of GO content and CZ modification on the structure, wear resistance, thermal conductivity, and mechanical properties of the NR/BR blended composites. It showed that adding 2 phr of GO resulted in excellent filler dispersion, significantly improving the tensile strength, elongation at break, tear strength, thermal conductivity, and wear resistance of the composites. The incorporation of CZ-rGO further increased the crosslinking density, vulcanization performance, and filler dispersion with enhanced mechanical properties, thermal conductivity, and wear resistance of the composites. Notably, the DIN abrasion volume was reduced to 77.88 mm³, surpassing the ISO 10247 standard for conveyor belt cover rubber in terms of wear resistance. The wear resistance of NR/BR/CZ-rGO composites is not only significantly higher than that of single NR- or SBR-based rubber composites, but also significantly higher than that of other binary rubber blend composites, and the CZ-rGO filler is simpler in composition and structure and exhibits a more prominent wear enhancement. This work provides guidance for an efficient and environmentally friendly approach to GO surface modification, as well as useful insights for the development of high wear-resistant rubber composites with excellent overall performance. [Display omitted] • Surface modification of GO using CZ in a one-step approach. • Synergistic reinforcement was obtained with CZ-GO and N234 in the NR/BR composites. • CZ-GO modulates the micro-interface between filler and rubber. • NR/BR composites owned the improved mechanical, thermal, and wear resistance properties. • Developed composites meet ISO 10247 for high wear-resistant conveyor belt cover rubber. [ABSTRACT FROM AUTHOR]

In this study, self-assembled three-dimensional (3D) reduced graphene oxide/nickel (rGO/Ni) nanofibers with hierarchical core-shell structure and vertically aligned graphene edge planes are synthesized as an efficient microwave absorption material. Electromagnetic multifunctional Ni chains form the skeleton of 3D nanofibers, and 2D rGO nanosheets are wrapped around the 1D Ni chain to form 3D rGO/Ni nanofibers via electrostatic self-assembly combined with a reduction method. Compared with the pristine Ni chain or rGO sheet, the unique vertically aligned graphene edge plane gives the 3D rGO/Ni nanofiber a much larger specific surface area and interlaced area between the 3D nanofibers. The hierarchical core-shell structure also provides abundant interfaces between the rGO and Ni chains, giving the 3D rGO/Ni nanofibers effective interfacial polarization loss. As a result, the 3D rGO/Ni nanofibers exhibit excellent microwave absorption properties. At a thickness of 2 mm, the minimum reflection loss of the nanofibers with only 15 wt% loading in paraffin reaches −50.52 dB, and the effective absorption bandwidth achieves 4.2 GHz. Moreover, the 3D rGO/Ni nanofibers also exhibit excellent dispersibility because of their special edge plane structure. This work provides an effective strategy for designing high-performance microwave absorption materials and is promising for applications in efficient electronics protection. Image 1 [ABSTRACT FROM AUTHOR]

In this work, to investigate the effect of electron motion mode on the microwave absorption performance, ferrite Fe 3 O 4 and graphene oxide (GO) were united by covalent bonding and subsequent reduction to fabricate microwave absorbing material (MAM) with excellent impedance matching characteristics and superb attenuation ability. Under the synergistic effect of the magnetic and dielectric properties, the Fe 3 O 4 -rGO hybrid nanocomposites present high absorption performance. Its minimum reflection loss (RL min) reached –47.46 dB when the thickness was 3.5 mm. The effective absorption bandwidth (EAB) was 5.86 GHz when the thickness was only 2.0 mm. XPS and FT-IR spectroscopy indicate the formation of amide bonds between the modified Fe 3 O 4 and functional GO. SEM, EDS, TEM and Raman spectroscopy were used to analyze the morphology and structure of the hybrid nanocomposites. The effects of bonding modes and component fractions on the electron motion and the resulting impedance matching of the hybrid nanocomposites were discussed. • A covalently bonded ferrite and graphene oxide wave absorbing composite was prepared. • Fe 3 O 4 -rGO absorber achieves broadband, low thickness, and high loss absorption. • The influence of covalent connections to the polarization chirality loss capacity was characterized. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The Ag/rGO@FeCo/WPU films with high EMI SE and low reflectivity is fabricated. • The film exhibits excellent EMI SE of 50.5 dB with the film thickness of only 300 μm. • Layered structural design provides the film very low microwave reflection of 0.49. • The films show cyclic EMI shielding stability under mechanical deformation. Abstract A highly efficient electromagnetic interference (EMI) shielding waterborne polyurethane (WPU) composite film with low microwave reflectivity is designed by constructing an FeCo alloy decoration reduced graphene oxide (FeCo@rGO) /nano silver (Ag) layered structure. The FeCo@rGO layer formed by natural sedimentation at the bottom of the WPU film acts as a microwave absorption layer, and the ultra-thin Ag layer covered on the top surface serves as a highly efficient shielding layer. This unique layered structure combines the microwave-reflecting characteristic of nano Ag and the microwave-absorbing characteristic of rGO@FeCo to achieve strong microwave shielding effectiveness (SE) with low microwave reflection. The obtained Ag/rGO@FeCo/WPU composite film (10 wt% rGO@FeCo and Ag layer of 500 nm in thickness), which is only 300 μm in thickness, possesses an outstanding EMI SE of 50.5 dB and the microwave reflection coefficient is as low as 0.49 (average SE R of 3.2 dB). This flexible and highly efficient shielding film with extremely low reflectivity is suitable for application in portable and wearable smart electronics, and this strategy offers a new method for designing the flexible electromagnetic interference shielding materials with low reflection characteristic. [ABSTRACT FROM AUTHOR]

Graphene-mediated surface-enhanced Raman scattering (SERS) substrates are currently explored for ultrasensitive detection and expected to provide uniform SERS response by the virtue of graphene and plasmonic metal nanostructures. Here, we integrated graphene oxide (GO) and anisotropic metal nanostructures to create a novel multiple coupling system, in which ultrathin GO as nanospacer was sandwiched between two layers of closely packed gold nanostars (AuNSts). The sandwiched hybrid was prepared through alternative loading of AuNSts and graphene oxide (GO) film via filtration and spin-coating methods in the absence of any polymer stabilizer or organic linkage agent. The morphologies and plasmon resonance of AuNSts could be tuned by simply adjusting the synthesis parameters. Due to the multi-dimensional plasmonic coupling in horizontally and vertically patterned AuNSts, extra chemical enhancement and outstanding molecule harvesting capability from GO interlayer, the as-prepared AuNSt-GO-AuNSt sandwich structures manifested ultrahigh sensitivity and excellent reproducibility (the signal variations <6%). A detection limit of rhodamine-6G (R6G) as low as 10 −13  M and a high enhancement factor of 6.64 × 10 7 were achieved. Particularly, the AuNSt-GO-AuNSt system was applied to detect erythrosine B and chrysoidin down to 10 −9  M as well as offer spectroscopic identification in complicated solutions, indicating great potential practical applications for the rapid and sensitive on-site monitoring, especially for food and environmental safety. [ABSTRACT FROM AUTHOR]

Three-dimensional reduced graphene oxide network deposition on Ni foam (3D rGO/NF) was successfully synthesized by a new process. Here, the structure and loading of rGO deposition on Ni foam could be easily controlled by the synthesis conditions. Furthermore, it was directly applied as the electrode of supercapacitor, in which the electrochemical behaviors of 3D rGO/NF with various structures were further compared in detail. As a result, the rGO film deposition on backbones of Ni foam electrode delivered a higher specific capacitance comparing to rGO aerogel deposition on Ni foam. The result was attributed to that the direct and close contact between rGO film and Ni foam was beneficial to the enhanced conductivity of the electrode, as well as the improvement of ion diffusion/transport into the electrode for the rGO film deposition on backbones of Ni foam. The works provided a new way to controlled synthesis of rGO network at large scale for in various applications. [ABSTRACT FROM AUTHOR]

In this study, the MnO 2 /reduced graphene oxide/Ni (MnO 2 /rGO/Ni) composite foam as a binder-free supercapacitor electrode was prepared by a facile method. The rGO film has been firstly coated on the skeletons of Ni foam current collectors by chemical deposition method and that have been used as substrates for preparation of a novel three dimensional rGO/Ni composite foam-supported porous MnO 2 film by the hydrothermal method. The structure of MnO 2 /rGO/Ni composite foam was characterized by Raman spectra, IR spectra and Scanning electron microscopy. It indicated that the high-quality rGO film have been coated on skeletons of Ni foam current collectors and the MnO 2 film had a 3D network microstructure, consisting of interlaced nanosheets. Furthermore, the binder-free MnO 2 /rGO/Ni composite foam electrode has been characterized by the cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectra. It exhibited excellent pseudocapacitive behavior with specific capacitance of 479.0 F/g. The capacitance could retain about 83.5% after 1000 charge–discharge cycles. This simple synthetic approach provides a convenient route for the large scale preparation of 3D porous MnO 2 /rGO/Ni composite foam for lots of applications in future. [ABSTRACT FROM AUTHOR]

The various shapes Fe 3 O 4 decorated reduced graphene oxide (Fe 3 O 4 /rGO) were prepared by one-step solution co-precipitation method, in which the shapes (sphere, rod and band) of Fe 3 O 4 in the nanocomposites could be carefully controlled by adjusting the mole ratio of Fe 2+ /Fe 3+ in the presence of rGO modified PVP. The structure of Fe 3 O 4 /rGO was characterized by SEM, EDS, TEM and Raman. Furthermore, the band Fe 3 O 4 /rGO modified glassy carbon electrode (GCE) was characterized by cyclic voltammetry (CV) and electrochemical impedance spectra (EIS). And the effect of shapes of Fe 3 O 4 decorated reduced graphene oxide on the electrochemical detection of Pb(II) was investigated in detail. It was found that the shape of Fe 3 O 4 had great effects on sensitivity. The band Fe 3 O 4 /rGO modified electrode toward Pb(II) showed high sensitivity (13.6 μA/μM), which was higher than that of spherical and rod Fe 3 O 4 /rGO modified electrode, respectively. The band Fe 3 O 4 /rGO was further demonstrated to be useful for the individual electrochemical detection of Cd(II) and Cu(II) in water for the first time. This report provides an opportunity to study relationship between the shapes and properties of Fe 3 O 4 decorated reduced graphene oxide with high performance. [ABSTRACT FROM AUTHOR]

Using carbon nanomaterials to construct self-lubricating polymer materials with porous self-lubricating structures has become an effective way to improve the tribological performance of polymer composites. The synergistic effect between 1.0 wt% graphene oxide (GO) and lubricating oil resulted in excellent tribological properties of polyamide 6 (PA6) composites under different loads and speeds. It indicated that the introduction of GO in porous PA6 matrix (GO/PA6) would provide enhanced tribological performance with the friction coefficient reduction by 23.4% and wear resistance improvement by 36.2%. This was explained by the lubricating oil stored in the pores of PA6 material would be released to the surface of the matrix material under the dual effect of load and temperature during the friction process. The released lubricating oil would formed a solid-liquid double lubrication structure with the well-dispersed GO in the matrix, thus the porous oil-immersed GO/PA6 composite materials demonstrates excellent tribological performance. This work provides a solid-liquid double lubrication strategy for enhancing the tribological properties of self-lubricating polymers, which would promote the self-lubricating polymer composites more widely applied in the field of friction materials. [Display omitted] • GO nano-filling porous oil-impregnated PA6 composites were prepared. • Friction coefficient reduced by 23.2% and wear resistance improved by 36.3%. • GO and oil formed solid-liquid double lubrication structure in the composites. • The synergistic strategy can be used to design high-performance composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new strategy for preparing GO-SiO 2 hybrids via amino-terminated HBP was developed for the first time. • The HBP on the SiO 2 surface not only reacted better with the groups on GO surface, but also participated in the curing reaction of epoxy resin. • GO-SiO 2 /epoxy composites displayed higher mechanical and thermal properties than that of GO or SiO 2 composites. • The improvement was attributed to the synergistic effect among GO and SiO 2 and the strong interaction with the epoxy matrix. The deposition of nano-silica (SiO 2) on graphene oxide (GO) surface via amino-terminated hyperbranched polymer (HBP) was designed to improve the dispersion and interfacial interaction between GO and epoxy resin. The structures and morphologies of GO and GO-SiO 2 sheets were characterized by FT-IR, XRD, XPS, TG, SEM and TEM. Epoxy composites containing GO and GO-SiO 2 with 0.1 wt% loadings were prepared and systemically investigated. It was indicated that the GO-SiO 2 /epoxy composites displayed higher mechanical and thermal properties than that of GO or SiO 2 composites. For epoxy composites containing 0.1 wt% GO-SiO 2 , the flexural strength increased by 20.57% and 23.58% compared to that of individual GO composites and individual SiO 2 composites, respectively. Furthermore, the reinforcing mechanisms have been also illuminated. This work is expected to be beneficial to the designing of adhesive-bonded composite structures or components. [ABSTRACT FROM AUTHOR]

Polymer composites with high thermal conductivity and good mechanical properties have considerable potential for application in modern micro-electronic devices. In this study, novel core-shell structured fillers (denoted as F-GA) were synthesized by covalently linking aluminum oxide modified with poly (dopamine) and graphene oxide. F-GA/natural rubber (NR) composites were prepared by vacuum-assisted filtration and their thermal conductivity and mechanical properties were investigated. The thermal conductivity of the F-GA/NR composites was 0.863 W/m·K at 25 wt% F-GA filler loading. In addition, the F-GA/NR composites exhibited outstanding mechanical properties and good electrical insulation properties. The interfacial thermal resistance was reduced because of the presence of covalent bonds and three-dimensional structures. The F-GA/NR composites prepared in the present study have a broad application prospects in advanced electronic packaging materials. [Display omitted] • Novel core-shell structured fillers were synthesized by covalently linking PDA@Al 2 O 3 and GO. • A thermal conductivity of 0.863 W/m·K is achieved for natural rubber-based composites. • Mechanical properties of natural rubber-based composites were enhanced. [ABSTRACT FROM AUTHOR]

• rGO nanosheets covered with polymeric nanospheres was facile synthesis. • d-Spacing between rGO nanosheets was modified by tuning the ratio of polymeric nanospheres to rGO. • The modified rGO nanosheets showed good re-dispersion and stability in organic solvents. The reduced graphene oxide (rGO) nanosheets were modified by using polymeric nanospheres to adjust the d-spacings between dry rGO nanosheets. The experimental and computational studies show that the incorporation of polymeric nanospheres can effectively increase the d-spacing between dry rGO nanosheets, and meanwhile provide good compatibility of rGO with organic solvents. Specifically, when the d-spacing between nanosheets is greater than 14.0 nm, the dried rGO nanosheets can be well redispersed and stabilized in various organic solvents. This study thus provides a new technology that can produce dry rGO nanosheets with good re-dispersibility and stability in various organic solvents on a large-scale in a more environmental friendly manner. [ABSTRACT FROM AUTHOR]