Visible-light-responsive photocatalysts can directly harvest energy from solar light, offering a desirable way to solve energy and environment issues. Here, we show that one-dimensional poly(diphenylbutadiyne) nanostructures synthesized by photopolymerization using a soft templating approach have high photocatalytic activity under visible light without the assistance of sacrificial reagents or precious metal co-catalysts. These polymer nanostructures are very stable even after repeated cycling. Transmission electron microscopy and nanoscale infrared characterizations reveal that the morphology and structure of the polymer nanostructures remain unchanged after many photocatalytic cycles. These stable and cheap polymer nanofibres are easy to process and can be reused without appreciable loss of activity. Our findings may help the development of semiconducting-based polymers for applications in self-cleaning surfaces, hydrogen generation and photovoltaics.

A hydrophilic poly(methacrylic acid-co-poly-(ethylene oxide) methyl ether methacrylate) copolymer with a trithiocarbonate reactive group was used in the free-radical, batch emulsion polymerization of styrene. It allowed fast polymerizations and high final conversions to be achieved, and the parameters for a good control over the formation of well-defined amphiphilic diblock copolymers were identified. These diblock copolymers self-assembled in situ into nanoobjects of various morphologies upon chain extension. Achieving a good control over the formed diblock copolymers was shown to be an important step toward a better understanding of the parameters that affect the shape and size of the self-assembled objects, the ultimate goal being the ability to predict and fine-tune them on purpose.

Self-assembled block copolymer nanofibers are attractive materials for multiple applications. We propose here a novel, very simple and straightforward method to prepare polymeric nanofibers at high solids contents directly in water. It is based on an aqueous emulsion polymerization process performed under living radical polymerization conditions, using the RAFT method.

ARTICLEa basic function to increase the strength of the interaction photocatalyst-pollutant. On the basis of the discussed theoretical considerations, the origin of the high acidity of Bi 2 WO 6 was attributed to the presence of specific sites located onto the lateral faces of platelets. Future work has to focus to control the morphology of platelets to increase the proportion of lateral faces.' ASSOCIATED CONTENT b S Supporting Information. For more details about MU-SIC calculations, the affinity constants and charge of surface groups for planes (100), ( 001), (101), and (10-1) are exposed here. This material is available free of charge via the Internet at http://pubs.acs.org.

Aqueous emulsion polymerizations of styrene were performed in the presence of a macromolecular reversible addition‐fragmentation chain transfer (RAFT) agent (macroRAFT) composed of acrylic acid (AA) and poly(ethylene oxide) methyl ether acrylate (PEOA), end‐capped by a reactive dodecyl trithiocarbonate group (P(AA‐co‐PEOA)‐TTC). The influence of the stirring speed or the presence of different amounts of a divalent salt, CaCl2, were investigated in this polymerization‐induced self‐assembly process, in which spherical and nonspherical nano‐objects were formed upon the synthesis of amphiphilic diblock copolymers in situ. It appeared that the addition of CaCl2 led to the controlled formation of different nano‐objects such as spheres, fibers or vesicles, whereas an appropriate stirring speed was required for the formation of nanofibers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

Bimetallic Pd−Au nanostructures were synthesized in the soft templates provided by surfactant hexagonal mesophases. The nanostructures are constituted by a core rich in gold and a Pd porous shell. The electrocatalytic activity of these nanostructures for ethanol oxidation in basic medium was compared with that of alloyed Pd−Au nanoparticles synthesized in solution. The Pd−Au alloy is active toward the oxidation of ethanol in an alkaline medium but is not durable in realizing this process. The Pdshell−Aucore nanostructures synthesized in mesophases are promising for application in direct ethanol fuel cells as they exhibit a very good electrocatalytic activity and a high stability.

Metal-boron alloys contain a boron covalent framework providing typical high chemical, mechanical, and thermal stability, which allows important applications, for example, for diborides (NbB 2 ) and hexaborides (CaB 6 ) as refractory materials.[1] New properties also arise from alloying; a prime example is the superconductivity of magnesium diboride, which exhibits the highest critical temperature (39 K) among classical superconductors.[2] Hexaborides are also relevant because of their field emission properties [3] and their potential for thermoelectricity (CeB 6 ).[4] Moreover, transition-metal borides are drawing attention as efficient (de)hydrogenation catalysts that can accelerate, for instance, emission of hydrogen from ammonia-borane or borohydrides within energyharnessing devices based on hydrogen technology.[5] Applications in hyperthermia, information storage, thermoelectricity, and catalysis would benefit from scaling down to the nanometer range, which could bring, as for all nanomaterials, modified, enhanced, and even novel properties that arise from the finite particle size. To date, only a few nanostructured borides have been reported. This paucity arises mainly because M-B systems are typically synthesized at high temperatures above 1100 8C.[6] Nanoscale materials have been obtained at lower temperatures (25-100 8C), but at the expense of crystallinity and stability, and such approaches yield pyrophoric compounds without applicability.[7] The scarce reported procedures for nanostructured crystalline systems rely on physical [5,8] or chemical methods, [9] and none of them is demonstrated to be generally applicable to the wide and rich family of borides. Moreover, the majority of crystalline metal borides has not yet been approached at the nanoscale, such as hard (HfB 2 ) or ultrahard (MoB 4 ) materials, catalysts, and ferromagnetic compounds (FeB). The development of a reliable, versatile, and general synthesis procedure towards such systems is therefore still eagerly demanded.One requirement to obtain such nanostructures is the use of relatively mild temperatures, which are still high enough to trigger crystallization but low enough to avoid excessive grain growth, ideally in the range 500-900 8C. Then, development of a solution route instead of standard solid-state reactions may contribute to full kinetic accessibility of the reaction space, which includes control of nanocrystal size and shape. [10] Because of the thermal instability of organic solvents in such conditions, we turned to inorganic molten salts, which are readily available and safe to apply at the targeted temperatures.Herein we present the use of such salt melts for the first general synthesis of metal boride nanocrystals. The method is based on a one-pot ionothermal process which is simple and relies on medium temperature, atmospheric pressure, and environmentally friendly solvents. Applicability to a wide range of compounds, formation of novel nanostructures, and control over the nanocrystal size and the material texture are demons...

An original preparation method, called “two solvents” method, allows the production of MnO2 nanowires patterned by SBA-15 silicas under mild conditions, with a preserved two-dimensional hexagonal structure, a 97% filling of the porosity by oxide nanowires, and a controlled microstructure. A comparison is made with Mn-loaded SBA-15 prepared by more conventional adsorption methods. In the latter case, MnO x particles inside and outside the silica grains, empty and filled mesopores, and several Mn oxides (MnO2, Mn2O3, and Mn3O4) were identified. Once the preparation method of Mn-loaded SBA-15 optimized, various X-ray scattering and adsorption techniques using synchrotron radiation were used to observe salient features of the MnO2 nanowires crystallization in situ upon calcination. X-ray absorption at the Mn K edge shows that the oxidation state of manganese increases from (II) to (IV) between 80 and 120 °C. The oxidation of the Mn(II) salt occurs at a temperature lower than that necessary for bulk manganese nitrate (200 °C), which confirms its confinement within the SBA-15 pores. β-MnO2 nanowires of defective pyrolusite type are identified by wide-angle diffraction. The comparison between diffraction results and simulations demonstrates that the nanowire diameter is similar to the mesopore diameter of the silica host. A small contraction of unit-cell parameters occurs upon the crystallization of β-MnO2 nanowires. A parallel overall intensity increase observed in small-angle X-ray diffraction is the fingerprint of a homogeneously filled porosity.