Gao Qing Max Lu

On the True Photoreactivity Order of {001}, {010}, and {101} Facets of Anatase TiO2 Crystals†

Contrary to conventional understanding, clean anatase {001} facets exhibit lower photoreactivity than {101} facets. Furthermore, the {010} facets showed the highest photocatalytic reactivity in generating OH radicals and hydrogen evolution. This behavior was revealed by studies on crystals grown hydrothermally to have a predominance of {001}, {101}, or {010} facets (left to right in picture(a) and (b)-(d), respectively).

Magnetic Nanocomposites with Mesoporous Structures: Synthesis and Applications

Magnetic nanocomposites with well-defined mesoporous structures, shapes, and tailored properties are of immense scientific and technological interest. This review article is devoted to the progress in the synthesis and applications of magnetic mesoporous materials. The first part briefly reviews various general methods developed for producing magnetic nanoparticles (NPs). The second presents and categorizes the synthesis of magnetic nanocomposites with mesoporous structures. These nanocomposites are broadly categorized into four types: monodisperse magnetic nanocrystals embedded in mesoporous nanospheres, microspheres encapsulating magnetic cores into perpendicularly aligned mesoporous shells, ordered mesoporous materials loaded with magnetic NPs inside the porous channels or cages, and rattle-type magnetic nanocomposites. The third section reviews the potential applications of the magnetic nanocomposites with mesoporous structures in the areas of heath care, catalysis, and environmental separation. The final section offers a summary and future perspectives on the state-of-the art in this area.

Monodisperse Yolk–Shell Nanoparticles with a Hierarchical Porous Structure for Delivery Vehicles and Nanoreactors†

Core–shell and hollow structures are powerful platforms for controlled release, confined nanocatalysis, and optical and electronic applications. A hybrid of core–shell and hollow structures, a special class of core–shell structure with a distinctive core@void@shell configuration, which are called yolk–shell or rattle-type structures, have attracted tremendous interest in recent years

Extension of The Stöber Method to the Preparation of Monodisperse Resorcinol–Formaldehyde Resin Polymer and Carbon Spheres

Sphere we go: Monodisperse resorcinol formaldehyde (RF) resin polymer spheres with finely tunable particle size ranging from 200 to 1000 nm (see pictures) are prepared by an extension of the Stober method. Pyrolysis of the RF spheres at 600°C under N atmosphere yields uniform carbon spheres with a volume shrinkage of 19%.

Nitrogen-doped carbon monolith for alkaline supercapacitors and understanding nitrogen-induced redox transitions

A nitrogen-doped porous carbon monolith was synthesized as a pseudo-capacitive electrode for use in alkaline supercapacitors. Ammonia-assisted carbonization was used to dope the surface with nitrogen heteroatoms in a way that replaced carbon atoms but kept the oxygen content constant. Ammonia treatment expanded the micropore size-distributions and increased the specific surface area from 383 m(2) g(-1) to 679 m(2) g(-1). The nitrogen-containing porous carbon material showed a higher capacitance (246 F g(-1)) in comparison with the nitrogen-free one (186 F g(-1)). Ex situ electrochemical spectroscopy was used to investigate the evolution of the nitrogen-containing functional groups on the surface of the N-doped carbon electrodes in a three-electrode cell. In addition, first-principles calculations were explored regarding the electronic structures of different nitrogen groups to determine their relative redox potentials. We proposed possible redox reaction pathways based on the calculated redox affinity of different groups and surface analysis, which involved the reversible attachment/detachment of hydroxy groups between pyridone and pyridine. The oxidation of nitrogen atoms in pyridine was also suggested as a possible reaction pathway.

In Situ Growth of a ZnO Nanowire Network within a TiO2 Nanoparticle Film for Enhanced Dye‐Sensitized Solar Cell Performance

ZnO nanowire networks featuring excellent charge transport and light scattering properties are grown in situ within TiO(2) films. The resultant TiO(2) /ZnO composites, used as photoanodes, remarkably enhance the overall conversion efficiency of dye-sensitized solar cells (DSSCs) by 26.9%, compared to that of benchmark TiO(2) films.

ZnS Branched Architectures as Optoelectronic Devices and Field Emitters

A unique ZnS branched architecture was fabricated by a facile thermal evaporation method. Stable UV emission at 327 nm and superior field emission with a low turn-on field, a high field-enhancement factor, a large current density, and small fluctuation were observed.

Ultrasmall manganese ferrite nanoparticles as positive contrast agent for magnetic resonance imaging

Reducing ferromagnetic particle size is an important strategy to improve their positive effect on imaging through the suppression of their negative effect, demonstrated by ultrasmall manganese ferrite nanoparticles prepared from an environmentally-friendly aqueous route. These ultrasmall particles exhibit pronounced paramagnetic characteristics and nontoxicity, making them efficient T1-positive contrast agent and manganese contrast agents for manganese enhanced MRI.

Diluted Magnetic Semiconductor Nanowires Prepared by the Solution-Liquid-Solid Method

Wiry frame: Manganese-doped cadmium selenide (Mn-CdSe) colloidal nanowires (see picture) exhibit ferromagnetism and good conductivity without any changed to their optical properties. The nanowires are synthesized by a novel solution-liquid-solid approach that offers a low-cost route towards magnetically active quantum wires with excellent potential applications in electronics, photonics, and spintronics. (Figure Presented).

Lattice Distortion Oriented Angular Self-Assembly of Monolayer Titania Sheets

Self-assembly of exfoliated monolayer titania sheets is investigated by detailed transmission electron microscopy and the force field calculations. It is demonstrated for the first time that slight but significant lattice distortions result in modified angular self-assembly of exfoliated monolayer Ti(0.87)O(2) sheets. These findings significantly broaden current knowledge of the self-assembly of exfoliated nanoscale layered sheets, which may render the potential manipulation of self-assembly of nanosheets.