Ultrafast Crystallization of Ordered Mesoporous Metal Oxides and Carbon in Seconds

This Communication describes a facile strategy coupling block copolymer-directed self-assembly with high-power Joule heating to form highly crystalline and long-range ordered mesoporous oxide and carbon nanostructures in just a few seconds. The combined approach is compatible with various self-assembled hybrid systems, generating mesoporous composites of γ-Al2O3-carbon, γ-Al2O3/MgO-carbon and anatase-TiO2-carbon with p6mm symmetry, as well as mesoporous non-close-packed carbon structures. Removing the polymer/carbon gives well-defined mesoporous all-γ-Al2O3 and all-anatase-TiO2 structures. Impregnation of chloroplatinic acid followed by Joule heating yields platinum nanoparticles decorated on the channel walls of mesoporous γ-Al2O3-carbon structures. The rapid formation of thermally stable and periodically ordered crystalline oxide, carbon and oxide-carbon structures. <br>

Ultrafast Crystallization of Ordered Mesoporous Metal Oxides and Carbon in Seconds

This Communication describes a facile strategy coupling block copolymer-directed self-assembly with high-power Joule heating to form highly crystalline and long-range ordered mesoporous oxide and carbon nanostructures in just a few seconds. The combined approach is compatible with various self-assembled hybrid systems, generating mesoporous composites of γ-Al2O3-carbon, γ-Al2O3/MgO-carbon and anatase-TiO2-carbon with p6mm symmetry, as well as mesoporous non-close-packed carbon structures. Removing the polymer/carbon gives well-defined mesoporous all-γ-Al2O3 and all-anatase-TiO2 structures. Impregnation of chloroplatinic acid followed by Joule heating yields platinum nanoparticles decorated on the channel walls of mesoporous γ-Al2O3-carbon structures. The rapid formation of thermally stable and periodically ordered crystalline oxide, carbon and oxide-carbon structures. <br>

Mesoporous oxide films grown on Sn foil using various anodizing modes in alkaline electrolyte

The mesoporous structures of tin oxide were obtained by a simple method of one-stage electrochemical anodizing of Sn foil in 1M NaOH in various anodizing modes. Anodizing in the pulse potentiostatic mode allowed determination of actual value of the voltage drop on the anode. For the first time the possibility of obtaining mesoporous oxide films on the surface of tin using galvanostatic mode of anodizing was demonstrated. It was found that the surface morphology of the obtained tin oxide layers is strongly dependent on the anodizing mode. Based on the data obtained, a two-stage mechanism was proposed for the growth of porous structures on the surface of tin in the galvanostatic mode including initial formation of the layer of SnO·xH2O which is subsequently oxidized to SnO2·xH2O mesoporouslayer.

Resolving Electron Injection from Singlet Fission-Borne Triplets into Mesoporous Transparent Conducting Oxides

Photoinduced electron transfer into mesoporous oxide substrates is well-known to occur efficiently for both singlet and triplet excited states in conventional metal-to-ligand charge transfer (MLCT) dyes. However, in all-organic dyes...

Electrocatalysis of oxygen reduction reaction on gold nanoparticles modified titanium dioxide films with different morphology

Dense and mesoporous titanium dioxide films have been obtained on titanium substrate by means of thermal oxidation, hydrolysis of polybutyltitanate, deposition of titanium dioxide sol, ultrasonic treatment and anodic oxidation and characterized by scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. Electrochemical activity of titanium dioxide films, initial and modified by gold nanoparticles, in oxygen reduction reaction (ORR) in alkaline medium has been studied by cyclic voltammetry. It has been demonstrated that the efficiency of the dense and mesoporous titanium dioxide films in ORR is determined by their morphology, structure and pore ordering degree. Modification of titanium dioxide films by gold nanoparticles results in the decrease in overpotential of the ORR. It has been found that the electrodes consisted of highly ordered layers of titania nanotubes with deposited gold nanoparticles demonstrate sufficiently higher electrocatalytic activity toward the oxygen electroreduction in comparison with TiO2/Au systems based on dense films and mesoporous films with disordered pore structure. Features of electrochemical behavior of TiO2/Au (nanotubes/nanoparticles) system are explained by the peculiarities of electron transport to the electrode surface and structure of space charge layer in the mesoporous oxide film.

Size-dependent electron transfer from atomically defined nanographenes to metal oxide nanoparticles

We analyze for the first time size-dependent electron transfer from atomically precise nanographenes to a mesoporous oxide electrode.

Silica gel solid nanocomposite electrolytes with interfacial conductivity promotion exceeding the bulk Li-ion conductivity of the ionic liquid electrolyte filler

The transition to solid-state Li-ion batteries will enable progress toward energy densities of 1000 W·hour/liter and beyond. Composites of a mesoporous oxide matrix filled with nonvolatile ionic liquid electrolyte fillers have been explored as a solid electrolyte option. However, the simple confinement of electrolyte solutions inside nanometer-sized pores leads to lower ion conductivity as viscosity increases. Here, we demonstrate that the Li-ion conductivity of nanocomposites consisting of a mesoporous silica monolith with an ionic liquid electrolyte filler can be several times higher than that of the pure ionic liquid electrolyte through the introduction of an interfacial ice layer. Strong adsorption and ordering of the ionic liquid molecules render them immobile and solid-like as for the interfacial ice layer itself. The dipole over the adsorbate mesophase layer results in solvation of the Li+ ions for enhanced conduction. The demonstrated principle of ion conduction enhancement can be applied to different ion systems.