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ENERGY HARVESTING AND STORAGE USING SMART NANOCOMPOSITE FILMS. JEMILIA POLIUS, ALABAMA A&M UNIVERSITY. Ms. Jemilia R. Polius, PhD Student Dr. Mohan Aggarwal, Advisor Alabama A&M University Department of Physics Smart [...]

Abstract: The catalytic wet peroxide oxidation of phenol was investigated over Zn[Fe.sub.2][O.sub.4] nano spinels under different conditions designed by the experimental design. Zn[Fe.sub.2][O.sub.4] nano oxide was synthesized by the sol-gel [...]

The synthesis and properties of a novel core-shell structured ternary magnetic nanocubes of MnZn ferrite are explained. These nanocubes are shown o exhibit much higher coercivity and field-cooled/zero-field-cooled characteristics, as compared to the normal ferrites.

The corundum-type [In.sub.2-2x][Zn.sub.x][Sn.sub.x][O.sub.3] solid solution (cor-ZITO) is prepared under a high pressure of 70 kbar. Powder X-ray diffraction patterns of co-ZITO has shown the expected unit cell contraction with increased cosubstitution, but no evidence is provided for ilmenite-type ordering of the substituted Zn and Sn.

Single-crystalline [Zn.sub.2]Ge[O.sub.4] nanobelts with lengths of hundreds of micrometers, thicknesses as small as 7 mm and aspect ratios of up to 10000 are prepared in a binary ethylenediamine/water solvent system by using a solvothermal route. The ultralong and ultrathin geometry of the [Zn.sub.2]Ge[O.sub.4] nanoribbon has promoted the photocatalytic activity toward reduction of C[O.sub.2] into renewable hydrocarbon fuel in the presence of water vapor.

The synthesis and properties of the all-amorphous, optically transparent and mechanically flexible thin-film transistors (TF-TFTs) are discussed. The approach used for the formation of various bilayers gate dielectrics is also presented.

The synthesis of InAs quantum dots (QDs) with a ZnCdS shell with bright and stable emission in the near-infrared (NIR, 700-900 nm) region which could be used for biological imaging applications is presented. Targeted cellular labeling which might allow multiplexed and low autofluorescence cellular imaging is also presented.

Three step novel tandem reaction due to treatment of an [gamma]-acyloxy-[alpha],[beta]-unsaturated ketone with bis(iodozincio)methane is described. The tandem reaction initiated by 1,4-Addition of bis(iodozincio)methane gives excellent yield of 1,3-diketones.

The article explains a new facile, phosphine-free, low-cost colloidal method, which can be employed for the synthesis of the quarternary-alloyed ZnCdSe quantum dots. The quantum dots are shown to be widely used in numerous biolabeling, biosensing and light-emitting diodes applications.

The synthesis experiments have shown that while no Re-Zn alloy or solid solution is formed, a novel [Re.sub.3]Zn[N.sub.x] ordered solid solution is formed with nitrogen occupying Re-coordinated cages. The studies have shown that unlike pure [Re.sub.3]Zn, the novel hexagonal [Re.sub.3]Zn[N.sub.x] structure is stabilized by nitrogen bond formation with rhenium.

The colloidal synthesis of [Cu.sub.2]ZnSn[S.sub.4] (CZTS) nanocrystals and their use in preparing prototype solar cells with a power conversion efficiency of 0.23% under AM 1.5 illumination are demonstrated.

The direct synthesis of [Cu.sub.2]ZnSn[S.sub.4] (CZTS) nanocrystals by using the hot-injection method is described. The studies have shown that pure stoichiometric CZTS nanocrystals are formed with an average particle size of 12.8 [plusmn] 1.8 nm and optical measurements have shown a band gap of 1.5 eV, which is optimal for a single-junction solar device.

An epitaxial growth of a ZnSe diffusion barrier for the dopants were used for successful synthesis of efficient Cu-doped InP quantum dots (Cu:InP d-dots) emitters. The newly developed d-dots emitters not only compensate for the emission wavelength of the existing noncadmium d-dots emitters, Cu- and Mn-doped ZnSe d-dots (450?610 nm), but also offer a complete series of efficient nanocrystal emitters based on InP nanocrystals.

An improved cothermal evaporation route is used for achieving quaternary semiconductor nanostructured alloys by using an example of [Zn.sub.x][Cd.sub.1-x][S.sub.y][Se.sub.1-y] nanobelts. Widely controlled alloy nanostructures via composition/light emission has provided a new material platform for applications in wavelength-tunable lasers, multicolor detectors, full-spectrum solar cells, light emitting diodes (LEDs) and color displays.

The ferroelectric characteristics of an epitaxial perovskite ZnSn[O.sub.3] thin film on a (111) SrRu[O.sub.3]/(111) SrTi[O.sub.3] substrate prepared by pulsed laser deposition are examined. The ZnSn[O.sub.3] thin film has displayed a high ferroelectric polarization.

The band gap ([E.sub.g]) and energetics of the conduction band (CB) and valence band (VB) are studied for the films of zinc stannate ([Zn.sub.2]Sn[O.sub.4]) nanoparticles of the inverse-spinel structure prepared by the hydrothermal method. The reverse trend seen in the open-circuit voltage in certain dye-sensitized solar cell (DSC) electrolytes is described in terms of the higher rates of electron-triiodide recombination of Ti[O.sub.2] despite the lower position of the [Zn.sub.2]Sn[O.sub.4] CB in the vacuum scale.

The ground-state hole-transfer processes are studied in a series of oxidized porphyrin triads (ZnZnFb) in order to determine the rates between the nominally equivalent sites (Zn/Zn). The rate constants obtained from the analysis have helped in the design of molecular constructs for a variety of solar-energy applications.

The crystal structure of the analogous compound [Ba.sub.2]Zn[O.sub.2][Ag.sub.2][Se.sub.2] is described. The studies have shown that when the Zn[O.sub.2] plane is placed under tension in order to accommodate the large [Ba.sup.2+], [Ag.sup.+] and [Se.sup.2-] ions, the square planar coordination of zinc by oxide is unsustainable.

The synthesis and structural and magnetic characterization of five [Mn.sub.3][Zn.sub.2] heterometallic complexes are described. The results provide insights into the spin-state changes due to cocrystallizing cation and terminal ligand and the origins of ferromagnetic exchange in [Mn.sup.3] triangles with chemically identical magnetic cores.

The structures of three quasicrystal approximant phases in the TM-Mg-Zn (TM = Hf, Zr, Ti) systems with the analyzed compositions [Hf.sub.5][Mg.sub.18][Zn.sub.77], [Zr.sub.5][Mg.sub.18][Zn.sub.77] and [Ti.sub.5.5][Mg.sub.17.5][Zn.sub.77] are prepared and their structures are analyzed by single-crystal X-ray diffraction. The characteristic structural disorder in the phases is related to the chemical intergrowth of different Friauf polyhedra.

The temperature-dependent electron paramagnetic resonance (EPR) spectrum of Cu(III) ions doped into [Ba.sub.2]Zn[(HC[O.sub.2]).sub.6].4[H.sub.2]O is studied at the Q-band frequencies to obtain structural information about the local environment. The structural data obtained from the lattice strain parameters are correlated with those from the [Ba.sub.2]Zn[(HC[O.sub.2]).sub.6].4[H.sub.2]O crystal structure.

A study was conducted to explore the adsorption and reaction of methanol and formaldehyde on two-dimensional PdZn alloys on a Pd(111) surface as a function o the Zn content in the alloy. The results obtained provide insight into the role of Zn in Pd/ZnO catalysts for the steam reforming of methanol (SRM).

Molecular dynamics simulations are used for studying the structural and dynamic properties of the interlayer species of the ZnAl layered double hydroxide containing interlayer chloride anions. The diffusion of the interlayer water molecules and the chemical potential of the interlayer water molecules are calculated.

A high-pressure synthesis of a novel polar crystal structure LiNb[O.sub.3]-type oxide ZnSn[O.sub.3] is reported. The polar structure is characterized by a large displacement of Zn based on strong covalent bonding between Zn and three O.

The synthesis of two new frameworks, Zn[(en).sub.3][Ag.sub.2][I.sub.4] and Ni[(en).sub.3][Ag.sub.2][I.sub.4] via self-assembled Ag[I.sub.2.sup.-] reaction in solution is reported. The method provides new synthetic pathway to generate new solid-state materials based on the concept of using simple clusters as building blocks to construct open-framework structures.

The results of using tetrahydrofuran-2,3,4,5-tetracarboxylic acid C4H4O(COOH)4 with nine coordinating oxygen atoms to link Co and Zn, in extended open-framework structures, are presented. It was observed that upon heating under vacuum, the zinc compound not only loses water but some of the zinc atoms move to different positions in the structure while preserving the crystallinity of the single crystals.

Nature Mater. doi:10.1038/nmat2542 (2009) Where temporary surgical implants are concerned, materials that decompose safely over time eliminate the need for costly and painful removal. Magnesium in its crystalline form has [...]