One-pot self-assembly of sisal-like TiO 2 on graphene-like carbon sheets via a novel two-phase interface-facilitated route Hongyi Gao a, * , Mengyi Jia a , Keyi Dong b , Liwen Xing a , Xiao Chen a , Dandan Jia a a Beijing Advanced Innovation Center for Materials Genome Engineering, Beijing Key Laboratory of Function Materials for Molecule & Structure Construction, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, PR China b Beijing National Day School, Beijing, 100039, PR China article info Article history: Received 12 May 2018 Received in revised form 25 October 2018 Accepted 27 October 2018 Available online 29 October 2018 Keywords: One-pot Self-assembly Sisal-like TiO 2 /graphene-like carbon sheets Two-phase interface abstract A Sisal-Like TiO 2 /Graphene-Like Carbon Sheets (SL-TiO 2 /GLCSs) composite was fabricated via a facile one-pot self-assembling route at a two-phase interface. The ingenious P123 was introduced to serve a dual function of carbon precursor and structure-directing agent, which first assembled at the water/oil interfaces and subsequently was in situ carbonized to GLCSs. Then the sisal-like TiO 2 grew gradually on the GLCSs along the preferred direction. This process shows several advantages such as simple processes, mild condition, low cost and good combination of SL-TiO 2 and GLCSs. The combination of SL-TiO 2 with GLCSs significantly helps the adsorption of substrates as well as promotes electron-hole pair separation, exhibiting good photocatalytic activity towards degradation of methylene blue (MB) compared to the pristine SL-TiO 2 and commercial P25. This strategy opens up new perspectives for fabricating novel composites of nanooxides/GLCSs. © 2018 Elsevier B.V. All rights reserved. 1. Introduction In the past decade, heterogeneous photocatalysis has emerged as a green and efficient technology in air cleaning, water purifica- tion, solar-fuel production and organic synthesis fields [1 ,2]. In particular, nano-structured titanium dioxide (TiO 2 ) has attracted significant attention as an ideal and powerful photocatalyst due to its high catalytic activity, good chemical stability, low-cost and nontoxicity, which has been intensively studied and applied for degradation of organic pollutants [3,4], decomposition of water into hydrogen and oxygen [5] and photocatalytic conversion of carbon dioxide to fuels [6,7]. Since the morphology, structure and size of the catalysts have significant influence on the photocatalysis properties, great efforts have been undertaken to fabricate nano- structured TiO 2 with various morphologies, such as nanosheet [8,9], nanorod [10], nanobelt [11], nanotube [12e14] and urchin- like structure composed of nanosheets or nanorods [15]. For example, urchin-like TiO 2 showed excellent photocatalysis prop- erties in comparison with conventional nanocrystallites due to its high surface-to-volume ratio and permeability [16, 17]. However, the rapid recombination rate of photogenerated electron-hole pairs of pure nano-structured TiO 2 is still a main limitation for its practical applications. Various strategies were developed to suppress the recombination of charge carriers and improve the photocatalytic activity of nano-structured TiO 2 , including noble metal deposition, interfacial nonmetal or transition metal doping, coupling with other semiconductors, and nitrogen doping [18]. For example, Sun et al. prepared N-doped TiO 2 and metal (Fe, Ni, Ag, or Pt) and N codoped TiO 2 photocatalysts, demonstrating enhanced photocatalytic activity due to the syner- getic effect [19,20]. Recently, combining TiO 2 nanostructures with two dimensional (2D) carbonaceous materials has been considered as one of the most promising strategies to construct high efficient TiO 2 -based photocatalysts, due to the large special surface area, superior electron mobility, high chemical stability and other outstanding properties of 2D carbonaceous materials [21 ,22]. The combination of TiO 2 and 2D carbonaceous materials has proven to be an efficient way to simultaneously possess good adsorptivity and facile charge transportation and separation, which could facilitate effective photodegradation of pollutants [23e32]. For example, Kamat et al. [23] synthesized graphene-TiO 2 composite photo- catalysts via UV-assisted reduction of graphene oxide in TiO 2 sus- pensions, opens up new ways to enhance adsorptivity and facilitate the charge separation of TiO 2 -based photocatalysts. Subsequently, Zhang et al. [28] synthesized P25-graphene composites using a * Corresponding author. E-mail address: hygao2009@163.com (H. Gao). Contents lists available at ScienceDirect Journal of Alloys and Compounds journal homepage: http://www.elsevier.com/locate/jalcom https://doi.org/10.1016/j.jallcom.2018.10.351 0925-8388/© 2018 Elsevier B.V. All rights reserved. Journal of Alloys and Compounds 776 (2019) 763e772