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Exploring inorganic flower-like nanosheets is of increasing interest not only for fundamental research, but also for development of devices due to their good chemical stability, versatility, and high surface-to-volume ratio. In this work, flower-like TiO2 nanosheets (FTN) are successfully synthesized by a facile hydrothermal method. Notably, a series of single-factor experiments are carried out to drive multiple functional components in order to integrate into a single flower-like nanostructure perfectly. In addition, these experimental results further reveal that alcohol/glycerol molar ratio acts in a vital role for preparing optimal flower-like morphology and structure of TiO2. Furthermore, the photodegradation pathways and mechanism of Levofloxacin (LVOF) by FTN are shown according to photodegradation intermediates of LVOF, trapping experiments, and ligand-to-metal charge transfer (LMCT) sensitizing effect. Therefore, the present work not only demonstrates the controlled synthesis of flower-like TiO2 nanosheets, but also provides a guide for constructing other inorganic flower-like nanosheets or TiO2-based photocatalysts with optimal morphology, structure and photocatalytic performance. [ABSTRACT FROM AUTHOR]

Constructing phase junction is an effective strategy to increase photocatalytic performance of titanium dioxide (TiO 2) because it can promote charge separation. However, both low surface area and unstable phase interface limit its further application. In this investigation, we introduce a structural regulation strategy to prepare anatase/rutile TiO 2 (A/R–TiO 2) hollow photocatalyst through in-situ growth of rutile TiO 2 on anatase TiO 2 hollow microspheres byheat treatment. The as-synthesized A/R–TiO 2 photocatalyst was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet–visible (UV–vis) spectroscopy. The results reveal that the A/R–TiO 2 hollow photocatalyst significantly promotes efficient charge separation due to the intimate contact of two phases within a single hollow sphere. Notably, A/R–TiO 2 exhibits more efficient than commercial TiO 2 (P25) towards the photodegradation of various pesticide pollutants, which suggests that such a structural design can be an effective method for rationally constructing TiO 2 -based photocatalyst with advanced performance. [Display omitted] • A/R–TiO 2 hollow photocatalyst was prepared through in-situ growth of rutile TiO 2 on anatase TiO 2. • A/R–TiO 2 exhibited more efficient than commercial TiO 2 (P25) in pesticides degradation. • The combination of heterophase homojunction and hollow structure was the key parameter in photocatalysis. • The A/R–TiO 2 heterophase homojunction suppresses the bulk recombination of photoinduced carriers. • The degradation pathways and charge transfer mechanism were detailed. [ABSTRACT FROM AUTHOR]

Considerable efforts have focused on pursuing the efficient removal of antibiotic contaminants by combining adsorbents with photocatalysts. However, the reported adsorbents/photocatalysts still suffer from critical drawbacks including low adsorption rate, low mineralization rate, and complicated preparation procedures, greatly restricting their practical application. In this work, we report a facile method to develop porous TiO 2 /BiOI adsorbent through a one-pot hydrothermal process and subsequently low-temperature calcination (280 °C). Adsorption experiment shows that porous TiO 2 /BiOI realizes almost complete removal (99.4%) of tetracyclines, far beyond the values of BiOI (20.2%) and TiO 2 (71.1%). Notably, one-pot synthesis promotes the mass production of TiO 2 /BiOI without obvious loss in adsorption capacity. More importantly, TiO 2 /BiOI adsorbent can be simply regenerated by complete photodegradation of the adsorbed tetracyclines on TiO 2 /BiOI, and regains above 98% of its adsorption capacity for 10 cycles, successfully overcoming the limitations of environment-unfriendly regeneration conditions, low adsorption capacity, and poor recyclability for most of the reported adsorbents/photocatalysts. Additionally, adsorption mechanism is deduced to be mainly electrostatic attraction, hydrogen bonding, and pore filling according to adsorption performance. Therefore, the design concept we present here provides a new perspective for the development of reactive adsorbents with excellent removal efficiency and recyclability through a facile one-pot synthesis. [Display omitted] • TiO 2 /BiOI reactive adsorbent was prepared by a facile one-pot hydrothermal method. • TiO 2 /BiOI showed excellent removal (>99%) of tetracycline from aqueous solution. • One-pot strategy realized the mass production of TiO 2 /BiOI without obvious loss in adsorption capacity. • TiO 2 /BiOI exhibited superior recyclability (>98%) up to 10 cycles of photo-regeneration and re-adsorption. • Key removal mechanism of tetracyclines was detailed. [ABSTRACT FROM AUTHOR]

TiO2 has been widely used as a photocatalyst and an electrode material toward the photodegradation of organic pollutants and electrochemical applications, respectively. However, the properties of TiO2 are not enough up to meet practical needs because of its intrinsic disadvantages such as a wide bandgap and low conductivity. Incorporation of carbon into the TiO2 lattice is a promising tool to overcome these limitations because carbon has metal-like conductivity, high separation efficiency of photogenerated electron/hole pairs, and strong visible-light absorption. This review would describe and discuss a variety of strategies to develop carbon-doped TiO2 with enhanced photoelectrochemical performances in environmental, energy, and catalytic fields. Emphasis is given to highlight current techniques and recent progress in C-doped TiO2-based materials. Meanwhile, how to tackle the challenges we are currently facing is also discussed. This understanding will allow the process to continue to evolve and provide facile and feasible techniques for the design and development of carbon-doped TiO2 materials. [ABSTRACT FROM AUTHOR]