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Mesporous surface-fluorinated TiO 2 (F-TiO 2 ) powders of anatase phase with high photocatalytic activity are prepared by a one-step hydrothermal strategy in a NH 4 HF 2 -H 2 O-C 2 H 5 OH mixed solution with tetrabutylorthotitanate (Ti(OC 4 H 9 ) 4 , TBOT) as precursor. The prepared samples are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, N 2 adsorption-desorption isotherms, UV-vis absorption spectroscopy, and transmission electron microscopy. The production of hydroxyl radicals ( • OH) on the surface of UVilluminated TiO 2 is detected by a photoluminescence (PL) technique with use of terephthalic acid as a probe molecule. The photocatalytic activity is evaluated by photocatalytic oxidation decomposition of acetone in air under UV light illumination. The results show that the photocatalytic activity of F-TiO 2 powders is obviously higher than that of pure TiO 2 and commercial Degussa P25 (P25) powders due to the fact that the strong electron-withdrawing ability of the surface tTi-F groups reduces the recombination of photogenerated electrons and holes, and enhances the formation of free OH radicals. Especially, the F-TiO 2 powder prepared at the nominal atomic ratio of fluorine to titanium (R F ) of 0.5 shows the highest photocatalytic activity and its rate constant k exceeds that of P25 by a factor of more than 3 times.

structured zeolites, with the main focus on the synthesis strategies that are available, with examples given from the literature. Available approaches are reviewed for the preparation of micro-mesoporous structured zeolites, micro-macroporous structured zeolites and micro-meso-macroporous structured zeolites. Furthermore, the enhanced mass transport properties of hierarchically structured zeolites, featuring additional larger pores in addition to the crystalline micropores, have also been described. The significant improvement in catalytic properties in a range of important reactions resulting from enhanced mass transport properties have also been discussed through several representative cases. It is the intent of this work to stimulate intuition into the optimal design of related hierarchically organized zeolites with desired characteristics.

Both plants and animals possess analogous tissues containing hierarchical networks of pores, with pore size ratios that have evolved to maximize mass transport and rates of reactions. The underlying physical principles of this optimized hierarchical design are embodied in Murray's law. However, we are yet to realize the benefit of mimicking nature's Murray networks in synthetic materials due to the challenges in fabricating vascularized structures. Here we emulate optimum natural systems following Murray's law using a bottom-up approach. Such bio-inspired materials, whose pore sizes decrease across multiple scales and finally terminate in size-invariant units like plant stems, leaf veins and vascular and respiratory systems provide hierarchical branching and precise diameter ratios for connecting multi-scale pores from macro to micro levels. Our Murray material mimics enable highly enhanced mass exchange and transfer in liquid–solid, gas–solid and electrochemical reactions and exhibit enhanced performance in photocatalysis, gas sensing and as Li-ion battery electrodes.

Stable superhydrophobic coatings were successfully achieved from thiol-ligand nanocrystals. Nanocrystals included VIII and IB metals and oxide nanoparticles, such as Fe, Co, Ni, Cu and Ag. We present a simple and available method that facilitates the synthesis of superhydrophobic textiles and sponges, in which the interaction between the nanocrystals and thiol plays a significant role in the formation of a special wetting surface. Meanwhile, the superhydrophobic textiles could also be endowed with new functionalities. For example, textiles with Fe 3 O 4 nanocoatings possess magnetic properties, and Ag nanocrystals provide an antibacterial effect. If perfluoroalkyl thiol was used to replace alkyl thiol, the as-modified surfaces became oleophobic from superoleophilic. The proposed strategy was fit for various nanoparticles from as-established methods, including the preparation in different polar solvents, and the usage of surfactants as capping agents. As-prepared superhydrophobic nanocoatings show good durability towards hot water, surfactant aqueous solutions, and ultrasonic treatment in nonpolar solvents. The superhydrophobic and superoleophilic nanocoatings were effectively used for application in oil/water separation.

Solar light is widely recognized as one of the most valuable renewable energy sources for the future. However, the development of solar-energy technologies is severely hindered by poor energy-conversion efficiencies due to low optical-absorption coefficients and low quantum-conversion yield of current-generation materials. Huge efforts have been devoted to investigating new strategies to improve the utilization of solar energy. Different chemical and physical strategies have been used to extend the spectral range or increase the conversion efficiency of materials, leading to very promising results. However, these methods have now begun to reach their limits. What is therefore the next big concept that could efficiently be used to enhance light harvesting? Despite its discovery many years ago, with the potential for becoming a powerful tool for enhanced light harvesting, the slow-photon effect, a manifestation of light-propagation control due to photonic structures, has largely been overlooked. This review presents theoretical as well as experimental progress on this effect, revealing that the photoreactivity of materials can be dramatically enhanced by exploiting slow photons. It is predicted that successful implementation of this strategy may open a very promising avenue for a broad spectrum of light-energy-conversion technologies.

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As a fascinating conjugated polymer, graphitic carbon nitride (g-CN) has attracted much attention for solving the worldwide energy shortage and environmental pollution. In this work, for the first time we report oxygen self-doping of solvothermally synthesized g-CN nanospheres with tunable electronic band structure via ambient air exposure for unprecedentedly enhanced photocatalytic performance. Various measurements, such as XPS, Mott-Schottky plots, and density functional theory (DFT) calculations reveal that such oxygen doping can tune the intrinsic electronic state and band structure of g-CNvia the formation of C-O-C bond. Our results show that the oxygen doping content can be controlled by the copolymerization of the precursors. As a consequence, the oxygen doped g-CN shows excellent photocatalytic performance, with an RhB photodegradation rate of 0.249 min and a hydrogen evolution rate of 3174 μmol h g, >35 times and ∼4 times higher than that of conventional thermally made pure g-CN (0.007 min and 846 μmol h g, respectively) under visible light. Our work introduces a new route for the rational design and fabrication of doping modified g-CN photocatalyst for efficient degradation of organic pollutants and H production.