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Taking advantage of the unique properties of reduced graphene oxide (rGO) and monoclinic crystalline titanium dioxide (TiO 2 (B)) nanomaterials, a novel rGO-TiO 2 (B) composite membrane (MrGO-TiO 2 (B)) was constructed by UV-light-assisted self-assembly of rGO and TiO 2 on a nylon membrane. The structure of MrGO-TiO 2 (B) was characterized by scanning electron microscopy, transmission electron microscopy, UV-visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analysis. Through 2D/2D self-assembly, rGO and TiO 2 (B) were more tightly combined, and then MrGO-TiO 2 (B) exhibited outstanding photocatalytic activity and an excellent methylene blue (MB) removal rate. MB was completely removed in 60 min at a constant rate of 0.042 min -1 by the MrGO-TiO 2 (B)/H 2 O 2 /MB system upon solar simulating Xe lamp irradiation. The synergistic effect of rGO and TiO 2 (B) facilitated the photocatalytic degradation of MB. TiO 2 (B) was excited and generated electrons and holes upon irradiation. Some electrons migrated to the surface of TiO 2 (B) to react with H 2 O 2 to produce hydroxyl radicals (OH), while the other electrons migrated to the surface of rGO to react with H 2 O 2 , producing OH. In addition, a number of superoxide radicals (O 2 - ) was detected. The holes in the valence band of TiO 2 (B) directly oxidized MB. The catalytic activity of MrGO-TiO 2 (B) toward MB degradation remained stable after four rounds of reuse. Therefore, the surface modification of a nylon membrane with TiO 2 (B) and rGO can serve as a promising route to fabricate photocatalytic membranes for use in the water treatment industry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

With the pollution of perfluoroalkyl substances (PFASs) became increasingly serious, the researches focused on removal of PFASs by adsorption-photocatalysis method has attracted considerable attention. To make the catalyst TiO 2 disperse uniformly as quantum dots onto hydrophobic surface which was liable to attract perfluorooctanoic acid (PFOA), the surfactant sodium dodecyl sulfate (SDS) were used in this work, which not only connected the hydrophilic TiCl 3 to the hydrophobic sulfonated graphene (SG) nanosheets, but also behaved as the molecular template for controlled nucleation and growth of the nanostructured TiO 2 . After 3D SG-TiO 2 QD nanosheets were fabricated, a series of 3D SG-TiO 2 QD aerogels were self-assembled by ice-template. TiO 2 uniformly distributed on the surface of SG aerogel at QD size level (2-3 nm) and the size of TiO 2 could be effectively regulated by concentration of SDS. Compared with aggregated TiO 2 material, 3D SG-TiO 2 QD aerogels owned higher adsorption and photocatalytic performance. Benefiting from the hydrophobic surface of 3D SG as well as dispersed TiO 2 QDs, 3D SG-TiO 2 QD could enrich PFOA instantaneously (0.0381/s) and photocatalytic decomposed them effectively (1.898 E -4 /s). PFOA degradation by hole and hydroxyl radicals proceeded via a stepwise mechanism. The column made of 3D SG-TiO 2 QD could remove PFOA persistently in cycles of permeation. 3D SG-TiO 2 QD possessed powerful adsorption-photocatalytic decomposition capability of PFOA and steady reusability performance. The present work highlights the individual roles and synergistic effect of TiO 2 QD and 3D SG for effectively removing PFOA., (Copyright © 2019 Elsevier B.V. All rights reserved.)