Self-Assembled Growth of Agln(MoO4)(2) Submicroplates into Hierarchical Structures and Their Near-Infrared Luminescent Properties

Layer-controlled hierarchical flowerlike AgIn(MoO4)(2) microstructures with "clean" surfaces using submicroplates as building blocks without introducing any template have been fabricated through a low-cost hydrothermal method. The near-infrared luminescence of lanthanide ion (Nd, Er, and Yb) doped AgIn(MoO4)(2) microstructures, in the 1300-1600 nm region, was discussed and is of particular interest for telecommunication applications. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, electron diffraction, and photoluminescence spectra were used to characterize these materials.

CuIn(WO4)(2) nanospindles and nanorods: controlled synthesis and host for lanthanide near-infrared luminescence properties

CuIn(WO4)(2) porous nanospindles and nanorods were synthesized through a low-cost hydrothermal method without introducing any template or surfactants. An interesting formation mechanism, namely "oriented attachment", was observed for the growth of nanorods based on the experimental process and the anisotropic intrinsic crystalline structure of CuIn(WO4)(2), which is uncommon in such a system. The near-infrared luminescence of lanthanide ions (Er, Nd, Yb and Ho) doped CuIn(WO4)(2) nanostructures, especially in the 1300-1600 nm region, was discussed and of particular interest for telecommunications applications. X-Ray diffraction, scanning electron microscopy, transmission electron microscopy, electron diffraction and photoluminescence spectra were used to characterize these materials.

Novel Near-Infrared Luminescent Hybrid Materials Covalently Linking with Lanthanide [Nd(III), Er(III), Yb(III), and Sm(III)] Complexes via a Primary beta-Diketone Ligand: Synthesis and Photophysical Studies

A series of novel, colorless, and transparent sot-gel derived hybrid materials Ln-DBM-Si covalently grafted with Ln(DBM-OH)(3)center dot 2H(2)O (where DBM-OH = o-hydroxydibenzoylmethane, Ln = Nd, Er, Yb, and Sin) were prepared through the primary beta-diketone ligand DBM-OH. The structures and optical properties of Ln-DBM-Si were studied in detail. The investigation results revealed that the lanthanide complexes were successfully in situ grafted into the corresponding hybrids Ln-DBM-Si. Upon excitation at the maximum absorption of ligands, the resultant materials displayed excellent near-infrared luminescence.

Synthesis, characterization, and near-infrared luminescent properties of the ternary thulium complex covalently bonded to mesoporous MCM-41

The crystal structure of a ternary Tm(DBM)(3)phen complex (DBM - dibenzoylmethane; phen = 1. 10-phenanthroline) and the synthesis of hybrid mesoporous material in which the complex covalently bonded to mesoporous MCM-41 are reported. Crystal data: Tm(DBM)(3)phen C59H47N2O7Tm, monoclinic P21/c, a = 19.3216(12) A, b = 10.6691(7) A, c = 23.0165(15)A, alpha = 90, beta = 91.6330(10), gamma = 90, V = 4742.8(5) A(3), Z = 4. The properties of the Tm(DBM)(3)phen complex and the corresponding hybrid mesoporous material [Tm(DBM)(3)phen-MCM-41] have been studied. The results reveal that the Tm(DBM)(3)phen complex is successfully covalently bonded to MCM-41.

Electrically-controlled near-infrared chiroptical switching of enantiomeric dinuclear ruthenium complexes

Enantiomerically pure dinuclear ruthenium complexes with 1,2-dicarbonylhydrazide as a bridging ligand are optically active in the visible and near infrared spectral regions depending on the oxidation states of the metal centers and are useful as an electrochemically driven near infrared chiroptical switch.

Bifunctional Au@Pt hybrid nanorods

The controlled synthesis of bifunctional Au@Pt hybrid nanorods has been realized through a simple wet chemical approach. Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV-vis-near infrared spectroscopy (UV-vis-NIR) were employed to characterize the obtained hybrid nanorods. TEM results indicate that the thickness of Pt nanoislands on the surfaces of gold nanorods can be easily tunable via controlling the molar ratio of An nanorods to the H2PtCl6. These Au@Pt hybrid nanorods have dual functions, which can be used not only for surface enhanced Raman spectroscopy (SERS), but also to exhibit good catalytic activity for 02 reduction. It is expected that these hybrid nanorods can be used as new functional building blocks to assemble novel three-dimensional (31)) complex multicomponent nanostructures, which are believed to be useful for electrochemical nanodevices.

Near infrared long lasting emission of Yb3+ and its influence on the optical storage ability of Mn2+-activated zinc borosilicate glasses

The near infrared long lasting phosphorescence of Yb3+ is observed in Yb3+ and Mn2+ codoped zinc borosilicate glasses. Compared with the glasses solely activated by Mn2+, when the Yb3+ ion is codoped, the red long lasting phosphorescence of the samples is largely improved in both brightness and persistent time but the photostimulated long lasting phosphorescence is greatly depressed. It is considered that the appearance of the phosphorescence of Yb3+ is due to the alteration of the energy transfer channel; additionally, Yb3+ also changes the trap depth of the glasses with the shallower trap predominating therefrom the red long lasting phosphorescence is improved and the photostimulated long lasting phosphorescence is degraded.

Organic photovoltaic cells with near infrared absorption spectrum

Organic photovoltaic cells with a strong absorption spectrum in the near infrared region were fabricated with the structure of indium tin oxide (ITO)/zinc phthalocynine (ZnPc)/lead phthalocynine (PbPc)/C-60/Al. PbPc has a broad and strong absorption, while the organic films of PbPc/C-60 showed an additional new absorption peak at 900 nm. The absorption in the near infrared region can harvest more photons to invert into photocurrent. Moreover, the introduction of ZnPc thin layer between ITO and PbPc further improved the new absorption peak and the collection of hole carriers at the electrode ITO, which increased the power conversion efficiencies to 1.95% and short-circuit current density to 9.1 mA/cm(2) under AM 1.5 solar spectrum.

Self-assembled monolayer growth of octanol on mica: Atomic force microscopy and Fourier-transform infrared spectroscopy studies

The growth kinetics of self-assembled monolayers formed by exposing freshly cleaved mica to octanol solution has been studied by atomic force microscopy (AFM) and Fourier-transform infrared spectroscopy (FTIR). AFM images of samples immersed in octanol for varying exposure times showed that before forming a complete monolayer the octanol molecules aggregated in the form of small islands on the mica surface. With the proceeding of immersion, these islands gradually grew and merged into larger patches. Finally, a close-packed film with uniform appearance and few defects was formed. The thickness of the final film showed 0.8 nm in height, which corresponded to the 40degrees tilt molecular conformation of the octanol monolayer. The growth mechanisms consisted of nucleation, growth, and coalescence of the submonolayer films. The growth process was also confirmed by FTIR. And the surface coverage of the submonolayer islands estimated from AFM images and FTIR spectra as a function of immersion time was quite consistent.

Comparative study by infrared spectroscopy and microcalorimetry of the CO adsorption over supported palladium catalysts

The adsorption of CO on Al(2)O(3), ZrO(2), ZrO(2)-SiO(2), and ZrO(2)-La(2)O(3) supported Pd catalysts was studied by adsorption microcalorimetry and infrared (TR) spectroscopy. Some interesting and new correlations between the results of microcalorimetry and IR spectroscopy have been found. The CO is adsorbed on palladium catalysts in three different modes: multibonded (3-fold), bridged (2-fold), both on Pd(lll) and (100) planes, and linear (1-fold) adsorbed species. The corresponding differential adsorption heats lie in the field of high (210-170 kJ/mol), medium (140-120 kJ/mol), and low (95-60 kJ/mol) values, respectively. The nature of the support, the reduction temperature, and the pretreatment conditions affect the surface structure of the Pd catalysts, resulting in variations in the site energy distribution, i.e., changes in the fraction of sites adsorbing CO with specific heats of adsorption. Moreover, the CeO(2); promoter addition weakens the adsorption strength of CO on palladium. Based on the exposed results, a correctness factor, which considers the percentages of various CO adsorption states, must be introduced when one calculates the Pd dispersion using CO adsorption data.

High-efficiency and low-cost hybrid nanomaterial as enhancing electrocatalyst: Spongelike AWN core/shell nanomaterial with hollow cavity

A high-efficiency and low-cost spongelike Au/Pt core/shell electrocatalyst with hollow cavity has been facilely obtained via a simple two-step wet chemical process. Hollow gold nanospheres were first synthesized via a modified galvanic replacement reaction between Co nanoparticles in situ produced and HAUCl(4). The as-prepared gold hollow spheres were employed as seeds to further grow spongelike Pt shell. It is found that the surface of this hybrid nanomaterial owns many Pt nanospikes, which form a spongelike nanostructure. All experimental data including scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis-near-infrared spectroscopy have been employed to characterize the obtained Au/Pt hybrid nanomaterial. The rapid development of fuel cell has inspired us to investigate the electrocatalytic properties for dioxygen and methanol of this novel hybrid nanomaterial. Spongelike hybrid nanomaterial mentioned here exhibits much higher catalytic activity for dioxygen reduction and methanol oxidation than the common Pt electrode.