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Functionalized knitted fabric, as a kind of flexible, wearable, and waterproof material capable of conductivity, sensitivity and outstanding hydrophobicity, is valuable for multi-field applications. Herein, the reduced graphene oxide (RGO)-coated knitted fabric (polyester/spandex blended) is prepared, which involves the use of graphite oxide (GO) by modified Hummers method and in-situ chemical reduction with hydrazine hydrate. The treated fabric exhibits a high electrical conductivity (202.09 S/cm) and an outstanding hydrophobicity (140°). The outstanding hydrophobicity is associated with the morphology of the fabric and fiber with reference to pseudo-infiltration. These properties can withstand repeated bending and washing without serious deterioration, maintaining good electrical conductivity (35.70 S/cm) and contact angle (119.39°) after eight standard washing cycles. The material, which has RGO architecture and continuous loop mesh structure, can find wide use in smart garment applications. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide/titanium dioxide nanotube (rGO/TNT) composites have superior properties, such as a large surface area, extraordinary mechanical strength, high carrier mobility, etc. However, the biosafety and biocompatibility of these composites, such as their influences on cell viability and cell functions, which are of paramount importance, are still not fully addressed. In this study, rGO/TNT nanocomposites were successfully synthesized through a modified hydrothermal treatment method. Then, the interactions between the rGO/TNT nanocomposites and Raw264.7 mouse monocyte-macrophage cells were further investigated. The results show that the rGO/TNT nanocomposites could be internalized by Raw264.7 cells and mainly gathered inside the cytoplasm. No rGO/TNT nanocomposites were observed in the nucleus. Moreover, the rGO/TNT nanocomposites exhibited low cytotoxicity toward Raw264.7 cells at a lower dose, though they may exhibit cytotoxicity to some extent at very high concentrations. In addition, the uptake of the nanocomposites influenced the cell cytoskeleton organization, while the cell adhesion and migration abilities were also impaired. [ABSTRACT FROM AUTHOR]

A novel composite photocatalyst, reduced graphene oxide (rGO) modified superlong TiO nanotubes (LTNTs) with length of about 500 nm, has been successfully synthesized by improved hydrothermal process and heating reflux method. The prepared rGO-LTNT catalysts have been characterized and analyzed by transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, powder X-ray diffraction (XRD), photoluminescence spectroscopy (PL) and electron paramagnetic resonance (EPR). The results from these investigations provided a deep insight into the physical structure and chemical composition of the rGO-LTNT nanocomposites and pure LTNT. Furthermore, the photocatalytic activity of rGO-LTNT nanocomposites for degradating methylene blue (MB) solution was evaluated under visible light irradiation. The obtained 1.5% rGO content of rGO-LTNT photocatalyst showed a purification of more than 50% MB in MB solution for an hour, which was about five times higher than that of the pure TNT. The results confirmed that the prepared rGO-LTNT nanocomposite photocatalysts showed excellent co-photocatalytic ability. That's because rGO played a critical role in utilizing solar light and increasing separation of the electron-hole pairs more efficiently, and which greatly accelerated the decomposition of organic pollutants in waste water or air. [ABSTRACT FROM AUTHOR]

Layered titanate nanosheets (TNS) were directly synthesized by one step in a special reaction system called weak base hydrothermal system, without organic stabilizer and washing or proton exchange. Reduced graphene oxide (rGO)/TNS nanocomposites were synthesized by improved hydrothermal treatment. The obtained samples were characterized by Scanning electron microscope, Transmission electron microscope, X-ray powder diffraction, Raman spectrum, Fourier Transform Infrared spectra, UV-Vis diffuse reflectance spectrum, Photoluminescence, X-rayphotoelectron spectroscopy, X-band electron paramagnetic resonance. The results confirmed that titanate nanosheets were homogeneously dispersed on rGO sheets, and three factors play an important part in the high photocatalytic performance of the samples, including the formation of a Ti-O-C bond expanding the light wavelength absorption range, the adsorption of contaminant molecules, the high separation rate of electron-hole pairs based on the sufficient contact of TNS and rGO nanosheets. The photocatalytic performance of as-prepared rGO/TNS nanocomposites were evaluated by degradation of methylene blue under visible-light irradiation (λ ≥ 400 nm). The acquired results showed that the photocatalytic performace of rGO/TNS nanocomposites were better than that of pure TNS. It could be attributed to the phenomenon that the photogenerated electrons in TNS were easily transferred to the rGO sheets via Ti-O-C between TNS and rGO. This process decreases the recombination rate of electron-hole pairs and lead to the improvement of photocatalytic activity. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)-TiO nanotube (TNT) composites sensitized by Meso-tetra (4-carboxyphenyl) porphyrin (HTCPP/rGO-TNT) have been synthesized successfully with improved hydrothermal and heat reflux synthesis process. The chemical structure and performances of HTCPP/rGO-TNT composites have been characterized by TEM-EDS-SAED, DRS and XRD. The influences of both rGO and/or HTCPP for TNT to adsorb and degrade Rhodamine-B (RhB) have been analyzed by DRS. In addition, the degradation results showed a purification of more than 93 % RhB in wastewater, which is about 4.6 times higher than that of the pure TNT. The experimental results revealed that HTCPP/rGO-TNT own superior degradation activity. This phenomenon is due to the excellent photons-capture system of the HTCPP, and the high photoinduced electron mobility characteristic of graphene acceptor. Thus, these materials can be employed to degrade organic pollutants, and effectively applied in wastewater quality control and its treatment. [ABSTRACT FROM AUTHOR]

Meso-tetra (4-carboxyphenyl) porphyrin (H 2 TCPP) loaded on the surface of TiO 2 nanotubes (TNTs) by modification of reduced graphene oxide (rGO) nanostructures has been successfully performed through improved hydrothermal and heating reflux composite technology. The influence of rGO and H 2 TCPP on the co-photocatalytic behavior of TNT during the degradation of Methylene blue (MB) were studied. The novel photocatalysts have been characterized and analyzed by high-resolution transmission electron microscopy (TEM), elemental mapping by energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL) and electron paramagnetic resonance (EPR). The results from these investigations provide a deeper insight into the materials chemistry of H 2 TCPP/rGO-TNT nanocomposites. Additionally, the photocatalytic activity was evaluated by the photodegradation of MB under irradiation with visible light. The degradation results showed a purification of more than 92% MB in wastewater, which is about 4.3 times higher than that of the pure TNT. The results confirm that the prepared H 2 TCPP/rGO-TNT nanocomposites possess superior absorption and co-photocatalytic activities. First, graphene works as the adsorbent, electron acceptor and transporter to efficiently increase the separation of the electron–hole pairs. Then it can accelerate the decomposition of organic pollutants. Second, the H 2 TCPP plays a critical role in capturing photons and expands the absorption wavelength to the visible light region when dealing with water resource. [ABSTRACT FROM AUTHOR]

In this paper, TiO 2 nanotubes (TNT) co-sensitized with copper(II) meso -tetra(4-carboxyphenyl)porphyrin (CuTCPP) and reduced graphene oxide nanosheets (rGO), which was fabricated through two-step improved hydrothermal method and heating reflux process. The effect of rGO and CuTCPP on the co-photocatalytic behavior of TNT for the degradation of Methylene Blue (MB) were measured under visible light irradiation. The photocatalysts have been characterized and analyzed by high-resolution transmission electron microscopy (TEM), selected area electronic diffraction (SAED), elemental mapping by energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and electron paramagnetic resonance (EPR). The results provide a deeper insight into the co-photocatalytic mechanism of CuTCPP/rGO-TNT nanocomposites. The degradation results showed a purification of more than 95% MB in wastewater, which is about 5 times higher than that of the pure TNT. The results also confirm the prepared CuTCPP/rGO-TNT nanocomposites possess superior co-photocatalytic activities. [ABSTRACT FROM AUTHOR]

Electric fabric heaters have demonstrated potential applications in a wide range of fields for medical electrothermal, human healthcare and athletic rehabilitation. Whereas, little attention has been paid to the resistance variations and the interface of electric heaters. Here, this paper focuses on the resistance temperature-sensitive behavior and interfacial electricity of reduced graphene oxide (RGO)/polyester (PET) fabrics, which are obatained through a facile and scalable dip-coating method. When a current of 0.055 ampere (A) is applied, the RGO/PET fabric can achieve an equilibrium temperature about 89 °C in 20 s, with a maximum heating rate of 11.78 °C/s. Besides, the relative resistance changes of RGO/PET fabric are linearly related to the temperature. When the RGO/PET fabric reaches its steady-state temperature of 89 °C, the value of ΔR/R0 drops by ∼30%, showing that the fabric is endowed with temperature sensitivity. These prominent results indicate that the RGO/PET fabric owns great promise in the field of wearable electric heaters. Notably, the contact resistance at the interface of RGO/PET fabric heater is investigated and the mechanism of the temperature in middle part of heater is higher than that of both ends is analyzed. This provides a qualitative decoupling analysis method for the study and analysis of interfacial electricity and electrothermal distribution of carbon materials. [ABSTRACT FROM AUTHOR]

Polymer-functionalized graphene oxide (GO) has superior properties such as large surface area, extraordinary mechanical strength, high carrier mobility, good stability in physiological media and low cytotoxicity, making it an attractive material for drug and gene delivery. Herein, we successfully synthesized GO with an average size of 168.3 nm by a modified Hummers' method. Branched polyethylenimine (PEI) and 6-armed polyethylene glycol (PEG) functionalized GO complexes (GO-PEI and GO-PEG) with different zeta potentials of 47.2 mV and −43.0 mV, respectively, were successfully synthesized through amide linkages between the COOH groups of GO and the NH 2 groups of PEI and PEG. Then, the interactions between GO-PEI and GO-PEG complexes and Raw264.7 mouse monocyte-macrophage cells were investigated. The GO-PEI and GO-PEG complexes could both be internalized by Raw264.7 cells. However, compared with the GO-PEG complex, the GO-PEI complex showed higher intracellular delivery efficiency in Raw264.7 cells. Moreover, it was found that the GO-PEI complex not only gathered in endosomes but also in the cytoplasm, whereas GO-PEG gathered in endosomes only. The MTT tests showed that both GO-PEI and GO-PEG complexes exhibited very low cytotoxicity towards Raw264.7 cells when at a low concentration. The cellular immune response test demonstrated the GO-PEG complex enhanced the secretion of IL-6, illustrating it was more stimulus towards macrophage cells. The above results indicated that the GO-PEI complex, with a positive surface charge, demonstrated better potential to be used in effective drug and gene delivery. [ABSTRACT FROM AUTHOR]

A novel porphyrin sensitized TiO 2 /graphene photocatalyst was synthesized via a simple method using TiO 2 nanowires, reduced graphene oxide and porphyrin. Reduced graphene oxide sheets are an excellent conductor that can inhibit the charge recombination and enhance the electron–hole separation of modified TiO 2 nanowires. Porphyrin sensitized on TiO 2 nanowires acts as a sensibilizer to increase the light absorption of the photocatalyst. The composite with a large superficial area shows improved photocatalytic property to decompose methylene blue under visible light irradiation. [ABSTRACT FROM AUTHOR]