Two-dimensional reduced graphene oxide-titania （RGO-TiO2） composites were prepared using a single- step hydrothermal method under various hydrothermal reaction conditions. The morphological and surface characteristi...Two-dimensional reduced graphene oxide-titania （RGO-TiO2） composites were prepared using a single- step hydrothermal method under various hydrothermal reaction conditions. The morphological and surface characteristics of the RGO-TiO2 composites and reference materials were determined. The RGO-TiO2 composites showed photocatalytic activity for the decomposition of two target pollutants that was superior to both pure TiO2 and RGO under fluorescent daylight lamp illumination. The photo- catalytic activity of the RGO-TiO2 composite increased as the hydrothermal treatment time increased from 1 to 24 h, but then it decreased as the time increased to 36 h, which indicated the presence of an optimal treatment time. RGO-TiO2 composites activated by violet light-emitting diodes （LEDs） displayed lower decomposition efficiency than those activated by a daylight lamp, likely because of the lower light intensity of violet LEDs （0.2 mW/cm2） when compared with that of the daylight lamp （1.4mW/cm2）. However, the photocatalytic decomposition of the target pollutants using the RGO-TiO2 composite was more energy-efficient using the violet LEDs. The photocatalytic reaction rates increased as the residence time decreased, whereas the reverse was true for the decomposition efficiency.展开更多
文摘Two-dimensional reduced graphene oxide-titania （RGO-TiO2） composites were prepared using a single- step hydrothermal method under various hydrothermal reaction conditions. The morphological and surface characteristics of the RGO-TiO2 composites and reference materials were determined. The RGO-TiO2 composites showed photocatalytic activity for the decomposition of two target pollutants that was superior to both pure TiO2 and RGO under fluorescent daylight lamp illumination. The photo- catalytic activity of the RGO-TiO2 composite increased as the hydrothermal treatment time increased from 1 to 24 h, but then it decreased as the time increased to 36 h, which indicated the presence of an optimal treatment time. RGO-TiO2 composites activated by violet light-emitting diodes （LEDs） displayed lower decomposition efficiency than those activated by a daylight lamp, likely because of the lower light intensity of violet LEDs （0.2 mW/cm2） when compared with that of the daylight lamp （1.4mW/cm2）. However, the photocatalytic decomposition of the target pollutants using the RGO-TiO2 composite was more energy-efficient using the violet LEDs. The photocatalytic reaction rates increased as the residence time decreased, whereas the reverse was true for the decomposition efficiency.
