Carbonaceous materials with high specific energy capacity are prime candidates for applications in rechargeable lithium batteries. The authors report the synthesis and characterization of ordered mesoporous carbon (CMK‐3), synthesized using ordered silica as a template, with high reversible specific capacity and good charge–discharge cycle characteristics. The performance of CMK‐3 is compared with that of carbon nanotubes, and its superiority is suggested to be related to the three‐dimensional ordered structure of CMK‐3.

A sonochemical method has been successfully used in order to incorporate MnO2 nanoparticles inside the pore channels of CMK‐3 ordered mesoporous carbon. Modification of the intrachannel surfaces of CMK‐3 to make them hydrophilic enables KMnO4 to readily penetrate the pore channels. At the same time, the modification changes the surface reactivity, enabling the formation of MnO2 nanoparticles inside the pores of CMK‐3 by the sonochemical reduction of metal ions. The resultant structures were characterized by X‐ray diffraction (XRD), nitrogen adsorption, and transmission electron microscopy (TEM). CMK‐3 with 20 wt.‐% loading of MnO2 inside CMK‐3 delivered an improved discharge performance of 223 mA h g–1 at a relatively high rate of 1 A g–1. Almost no decrease in specific capacity is observed for the second cycle, and a discharge capacity of more than 165 mA h g–1 is retained after 100 cycles. This is attributed to the nanometer‐sized MnO2 formed inside CMK‐3 and the high surface area of the mesopores (3.1 nm) in which the MnO2 nanoparticles are formed.

The design of a delivery system was reported based on stimuli-responsive poly(N-isopropylacrylamide) (PNIPA) inside a mesostructured cellular foam (MCF) via atom transfer radical polymerization (ATRP), and the control of drug release in response to the environmental temperature was investigated. The successful synthesis of PNIPA inside the MCF was confirmed by Fourier transform infrared (FT-IR), transmission electron microscopy (TEM) and nitrogen adsorption/desorption measurements. Control of drug release through the porous network was performed by measuring the uptake and release of ibuprofen (IBU). The delivery system of MCF-PNIPA demonstrated a high IBU storage capacity of 58 wt% (IBU/silica), which is much higher than that reported for functional SBA-15 (37 wt%). The multilayer polymers inside the pores of the MCF were considered to form an internal cavity for drug molecules in addition to responding to changes in external temperature.

Abstract"Nano tungsten oxide (WO3) particles were synthesized on the surface of graphene (GR) sheets by using a simple sonochemical method. The obtained composite, WO3@GR, was characterized by X-ray diffraction, N-2 adsorption/desorption analysis, thermo-gravimetric analysis, Raman spectroscopy and UV-vis diffuse reflectance spectra measurements. It was found that chemical bonds between the nano WO3 particles and the GR sheets were formed. The average particle size of the WO3 was evidenced to be around 12 nm on the GR sheets. When used as photocatalyst for water splitting, the amount of evolved O-2 from water for the WO3@GR composite with 40 wt% GR inside was twice and 1.8 times as much as that for pure WO3 and mixed-WO3/GR, respectively. The excellent photocatalytic property of the WO3@GR composite is due to the synergistic effects of the combined nano WO3 particles and GR sheets. The sensitization of WO3 by GR enhances the visible light absorption property of WO3@GR. The chemical bonding between WO3 and GR minimizes the interface defects, reducing the recombination of the photo-generated electron-hole pairs. Furthermore, the GR sheets in the WO3@GR composite enhance electrons transport by providing low resistance conduction pathways, leading to improved photo-conversion efficiency. The methodology opens up a new way of obtaining photoactive GR-semiconductor composites for photodissociating water under visible light." Nano tungsten oxide (WO 3 ) particles were synthesized on the surface of graphene (GR) sheets by using a simple sonochemical method. The obtained composite, WO 3 @GR, was characterized by X-ray diffraction, N 2 adsorption/desorption analysis, thermo-gravimetric analysis, Raman spectroscopy and UV-vis diffuse reflectance spectra measurements. It was found that chemical bonds between the nano WO 3 particles and the GR sheets were formed. The average particle size of the WO 3 was evidenced to be around 12 nm on the GR sheets. When used as photocatalyst for water splitting, the amount of evolved O 2 from water for the WO 3 @GR composite with 40 wt% GR inside was twice and 1.8 times as much as that for pure WO 3 and mixed-WO 3 /GR, respectively. The excellent photocatalytic property of the WO 3 @GR composite is due to the synergistic effects of the combined nano WO 3 particles and GR sheets. The sensitization of WO 3 by GR enhances the visible light absorption property of WO 3 @GR. The chemical bonding between WO 3 and GR minimizes the interface defects, reducing the recombination of the photo-generated electron-hole pairs. Furthermore, the GR sheets in the WO 3 @GR composite enhance electrons transport by providing low resistance conduction pathways, leading to improved photo-conversion efficiency. The methodology opens up a new way of obtaining photoactive GR-semiconductor composites for photodissociating water under visible light.

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We developed a highly efficient photocatalyst for both H2 and O2 generation under visible-light irradiation by attaching Bi2WO6 (BWO) nanocrystals on graphene nanosheets to produce a graphene-Bi2WO6 composite (Gr-BWO-T). The composite was prepared by a sonochemical method where graphene oxide (GO) served as the support on which BWO formed in situ. Bi2WO6 nanoparticles with the size of 30-40 nm were homogeneously dispersed on the surface of graphene sheets, due to their bonding with graphene. When used as a photocatalyst under visible-light irradiation, O2 production rate reached a value up to 20.60 μmol h(-1), 4.18 times higher than that of bare BWO, resulting from the strong covalent bonding between graphene and BWO nanoparticles. The chemical bonding facilitated the electron collection and transportation and inhibited the recombination of photo-generated charge carriers, even in this system with a large amount of graphene inside (40 wt%). More interestingly, H2-production by Gr-BWO-T was also observed to be as high as 159.20 μmol h(-1). This could be ascribed to the existence of the graphene that led to decrease in conduction band potential and resulted in a more negative reduction potential than H(+)/H2. This facile sonochemical approach provides a new strategy for engineering ternary compound nanoparticles on graphene sheets, with great potential application in energy conversion.

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