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Novel phenyl-modified magnetic graphene/mesoporous silica (MG-MS-Ph) composites with hierarchical bridge-pore structure were successfully synthesized. The magnetic graphene (MG) as bridge were obtained by one-step solvothermal approach and then phenyl-functionalized mesoporous silica (MS-Ph) as pore modified the MG surfaces through one-pot facile strategy. The resulting MG-MS-Ph exhibited large surface area (446.5 m 2 g −1 ), highly ordered mesopores with uniform pore size (2.8 nm) and pore volume (0.32 cm 3 g −1 ) and higher saturation magnetization (25 emu g −1 ). These wonderful features made MG-MS-Ph as a promising magnetic solid-phase extraction adsorbent for the removal of pesticides from wastewater. Batch adsorption studies indicated that the novel composites exhibited superior adsorption capacity of pesticides compared with other adsorbents including Activated carbon, Multi-walled carbon nanotube and Single-walled carbon nanotube. Therefore, MG-MS-Ph as a low cost and efficient adsorbents for the removal of toxic pesticides would be economically and technically feasible. [ABSTRACT FROM AUTHOR]

In this study microwave-assisted reduction (MrGO) and direct reduction of graphene oxide (rGO) by Ti powders were established, and the effect of the reaction conditions on the reduction were discussed. The results showed that GO can be effectively reduced by both methods, however, microwave assistance can greatly shorten the reduction time. The produced Ti ions from the reaction of Ti powder with GO were transferred to TiO 2 by hydrolysis and formed MrGO/TiO 2 and rGO/TiO 2 . They were used as adsorbents for the removal of methylene blue (MB). MrGO/TiO 2 showed a higher adsorption capacity ( q max , 845.6 mg/g) than rGO/TiO 2 ( q max , 467.6 mg/g). Investigation on the adsorption MB onto MrGO/TiO 2 was conducted and demonstrated that adsorption kinetics followed the pseudo second-order kinetics model and the adsorption isotherm was well described by the Langmuir isotherm model. The recycling of MrGO/TiO 2 was achieved by photocatalytic degradation of MB catalyzed by MrGO/TiO 2 itself. [ABSTRACT FROM AUTHOR]

Adsorption and advanced oxidation technology are important means to remove organic pollutants, and the combination of adsorption and catalytic degradation to construct a multi-field coupled system can realize valid adsorption and degradation of organic contaminants. In this paper, CuBi 2 O 4 supported by a nonmetallic element-modified graphene hydrogel composite structure CuBi 2 O 4 /X-rGH (X = N, P, S, B) was synthesized and applied to the efficient removal of organic pollutants. We found that the doping of nonmetallic elements enhances the graphene conjugated large π-bond system, which not only improves the adsorption performance of pollutants but also increases the graphene conductivity and builds more carrier transport channels, which is beneficial to the photocatalytic Fenton synergistic degradation activity. Among them, CuBi 2 O 4 /P-rGH could achieve 90 % degradation of phenol (50 ppm) after 20 min of turning on the light, which was nearly 2 times more than the degradation activity of CuBi 2 O 4 /rGH. Electron paramagnetic resonance (EPR) and quenching experiments proved that ·OH was the main active species in the synergistic degradation process, and the mechanism of adsorption of nonmetallic modified graphene hydrogel hybrid catalysts and in situ photocatalytic Fenton degradation of pollutants was proposed. [ABSTRACT FROM AUTHOR]

Adsorption and advanced oxidation technology are important means to remove organic pollutants, and the combination of adsorption and catalytic degradation to construct a multi-field coupled system can realize valid adsorption and degradation of organic contaminants. In this paper, CuBi 2 O 4 supported by a nonmetallic element-modified graphene hydrogel composite structure CuBi 2 O 4 /X-rGH (X = N, P, S, B) was synthesized and applied to the efficient removal of organic pollutants. We found that the doping of nonmetallic elements enhances the graphene conjugated large π-bond system, which not only improves the adsorption performance of pollutants but also increases the graphene conductivity and builds more carrier transport channels, which is beneficial to the photocatalytic Fenton synergistic degradation activity. Among them, CuBi 2 O 4 /P-rGH could achieve 90 % degradation of phenol (50 ppm) after 20 min of turning on the light, which was nearly 2 times more than the degradation activity of CuBi 2 O 4 /rGH. Electron paramagnetic resonance (EPR) and quenching experiments proved that ·OH was the main active species in the synergistic degradation process, and the mechanism of adsorption of nonmetallic modified graphene hydrogel hybrid catalysts and in situ photocatalytic Fenton degradation of pollutants was proposed. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) graphene aerogels–mesoporous silica (GAs–MS) frameworks were successfully fabricated. The interconnected macropores were obtained from hydrothermally assembled 3D GAs, while the mesopores were generated by the silica uniformly grown on the surface of graphene. The resulting GAs–MS exhibited narrow mesopore size distribution (1.87 nm), high surface area (1000.80 m 2 g −1 ), and hierarchical macro- and mesoporous structures. These wonderful features made GAs–MS as a promising adsorbent for the removal of hazardous phenols from wastewater. The adsorption study implied that the novel materials exhibited superior adsorption capacity of phenols to such as phenol, catechol, resorcinol and hydroquinone, with removal efficiencies of 68.6%, 86.6%, 91.1% and 94.7%, respectively. [ABSTRACT FROM AUTHOR]