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The mononuclear Zn(Ⅱ) complex [Zn(2,6-PDA)(phen)H2O]·H2O (1) and binuclear Cu(Ⅰ) complex{[Cu(μ-Ⅰ)(phen)H2O]·H2O}2 (2) (2,6-H2PDA=2,6- pyridinedicarboxylic acid，phen=1,10- phenanthroline monohydrate) have been prepared with hydro-thermal synthesis method. These complexes have been characterized with single-crystal X-ray, elemental analysis, and IR spectroscopy. The fluorescence spectra of 1 and 2 are studied in solid-state and dimethyl sulfoxide (DMSO) solution. The maximum absorption peak of 1 and 2 are at 253 nm and 242 nm respectively, which are red shift to that of the phen ligand with inceased intensity. It may be assigned to the intraligand π→π* transition of the phen ligand that is modified by the Zn(Ⅱ) or Cu(Ⅰ) ions. On the basis of the coordination, the absorption of organic ligands in the ultraviolet region is increased, which is better for the energy absorption of the ligand. 1 and 2 all showed blue light emission. The emission peak of 1 and 2 have experienced a red shift (ca. 55 and 23 nm) in the solid state (λem = 407, 434, 467 nm for 1, 442, 469, 501 nm for 2) compared to in DMSO solution (λem = 361, 379, 392 nm for 1, 422, 443, 461 nm for 2). The red shift phenomenon can be attributed to the π-stacking of the aromatic rings and other intermolecular Interactions in these molecules in the solid state. Especially, the strong Cu(Ⅰ)…Cu(Ⅰ) interaction of 2 can decrease the HOMO—LUMO energy gap with the red-shifted emission wavelength.

This work reports on two new complexes with the general formula [Cd3(IBA)3(Cl)2(HCOO)(H2O)]n (1) and {[Cd1.5(IBA)3(H2O)6]·3.5H2O}n (2), which can be synthesized by the reaction of Cd(II) with rigid linear ligand 4-HIBA containing imidazolyl and carboxylate functional groups [4-HIBA = 4-(1H-imidazol-1-yl)benzoic acid]. Single-crystal X-ray diffraction analyses indicate that complex 1 is a 2D "wave-like" layer structure constructed from trinuclear units and complex 2 is just a mononuclear structure. Surprisingly, both complexes 1 and 2 appear as a 3D supramolecular network via intermolecular hydrogen bonding interactions. What's more, due to their strong UV-visible absorption, 1 and 2 can be employed as co-sensitizers in combination with N719 to enhance dye-sensitized solar cell (DSSC) performance. Both of them could overcome the deficiency of the ruthenium complex N719 absorption in the region of ultraviolet and blue-violet, and the charge collection efficiency is also improved when 1 and 2 are used as co-sensitizers, which are all in favor of enhancing the performance. The DSSC devices using co-sensitizers of 1/N719 and 2/N719 show an overall conversion efficiency of 8.27% and 7.73% with a short circuit current density of 17.48 mA cm(-2) and 17.39 mA cm(-2), and an open circuit voltage of 0.75 V and 0.74 V, respectively. The overall conversion efficiency is 27.23% and 18.92% higher than that of a device solely sensitized by N719 (6.50%). Consequently, the prepared complexes are high efficiency co-sensitizers for enhancing the performance of N719 sensitized solar cells.

We design two novel d10 metal complexes [Zn(3-qlc)2]n (Zn1), [Cd(3-qlc)2]n (Cd1) (3-Hqlc = quinoline-3-carboxylic acid), which display similar 2D layer structures, and further form 3D 6-connected primitive cubic (pcu) network topology via π⋯π stacking interactions with the point symbol {412·63}. Complexes Zn1 and Cd1 exhibit tunable luminescence and photovoltaic properties as a new type of multifunctional materials. Zn1 and Cd1 show tunable luminescence from blue to green by varying the temperature in the solid state. What's more, both of them exhibit excellent aggregation-induced emission (AIE) properties in DMSO/water mixtures. Encouraged by the UV-visible absorption in an ethanol solution result, Zn1 and Cd1 can be considered as co-sensitizers in combination with N719 to investigate their effect on enhancing the dye-sensitized solar cells (DSSCs) performance. Zn1 and Cd1 could overcome the deficiency in the ruthenium complex N719 absorption in the ultraviolet and blue-violet region, offsetting competitive visible light absorption of I3− and reducing the charge recombination of injected electrons. After being co-sensitized with Zn1 and Cd1, the devices co-sensitized by Zn1/N719 and Cd1/N719 yield an overall efficiency of 7.75% and 7.70%, which are 44.59% and 43.66% higher than that of the device sensitized only by N719 (5.36%).

Based on a new design of 4-cyanobenzyl-based 1,2,4-triazole ligand 4-(1,2,4-triazolylmethyl) cyanobenzene (TMCB), a series of cadmium complexes 1–5′ from a mononuclear to three-dimensional (3D) structure have been synthesized through hydro(solvo)thermal reactions; they were generally formulated as [Cd(TMCBA)2]n (1), [Cd(TMCB)(1,4-bda)(H2O)]n (2), {[Cd2(TMCB)4(1,4-bda)2(H2O)2]n·3H2O}n (3), {[Cd(TMCB)4(H2O)2]·(NO3)2·(H2O)2}n (4), [Cd1.5(1,4-bda)1.5(DMF)2]2n (5) and [Cd1.5(1,4-bda)1.5(DMF)2]2n (5′) (TMCBA = 4-(1,2,4-triazolylmethyl) benzoic acid, which is formed from the hydrolysis of TMCB; 1,4-H2bda = 1,4-benzenedicarboxylic acid; the difference between two genuine supramolecular isomers of 5 and 5′ is the use of TMCB as the additive agent for the reaction). Complexes 1–5′ exhibit tunable luminescence with emission maxima containing deep blue, blue, light blue, green and deep green region at 298 K or 77 K in both different solvents (polarity: DMSO > CH3OH > CHCl3) and solid state. Interestingly, the good thermal stability accompanied by their compensated adsorption to ruthenium complex N719 in the region of low wavelength, enabled 1 and 4 to serve as co-sensitizers in combination with N719 in dye sensitized solar cells (DSSCs). After co-sensitization with N719, the overall conversion efficiency of 1 and 4 were found to be 7.68% and 6.85%, which are 40.40% and 25.23% higher than that for DSSCs only sensitized by N719 (5.47%) under the same conditions, respectively. The improvement in efficiency is attributed to the fact that complexes 1 and 4 overcome the deficiency of N719 absorption in the low wavelength region of ultraviolet and blue-violet, offset competitive visible light absorption of I3− and reduce charge recombination due to the formation of an effective cover layer of the dye molecules on the TiO2 surface. As a result, the synthesized complexes are promising candidates as co-adsorbents and co-sensitizers for highly efficient DSSCs.

Highly ordered TiO 2 nanotube arrays were successfully prepared by electrochemical anodization in a formamide-based electrolyte containing 0.5 wt.% NH 4 F and 2 vol.% H 2 O. The effects of the calcining temperature, the calcining time and the heating rate on the formation of the TiO 2 nanotube arrays were investigated in detail. The morphological changes and phase transformations of the TiO 2 nanotubes were analyzed by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It was found that the calcining temperature and the calcining time determined the crystal phase, while the heating rate was only beneficial to altering the crystallinity. UV–vis diffuse reflectance spectroscopy was used to examine changes in the band gap energy. For applications to dye sensitized solar cells, a maximum conversion efficiency was achieved at 500 °C for 2 h with a heating rate of 10 °C/min, which is attributed to the highly crystalline anatase and the lower surface defect concentrations of the nanotubes. The optimum calcination conditions help to retard the electron recombination and allow higher dye absorption capacities, thereby increasing V oc and J sc .

Highly ordered TiO 2 nanotubes grown on a Ti substrate are conveniently modified with samarium oxide (Sm 2 O 3 ) by a hydrothermal method for use in back-illuminated dye-sensitized solar cells. As a down-conversion luminescence material, samarium oxide improves the UV radiation harvesting and thus increases the photocurrent. The results show that Sm 2 O 3 –modified TiO 2 nanotubes can increase the short-circuit current and the conversion efficiency of dye-sensitized solar cells. When TiO 2 nanotubes are modified by 0.02 M Sm 2 O 3 , the efficiency is improved by 73.1% compared with bare TiO 2 nanotubes.

Highly-ordered TiO2 nanotube arrays were successfully fabricated by electrochemical anodization of titanium. The morphology of TiO2 nanotube arrays, the length and pore size were represented by field emission scanning electron microscopy (FE-SEM). The parameters of various anodization including F- concentration, reaction temperature and anodization voltage were investigated in detail. The results show that as-prepared TiO2 nanotube arrays possess good uniformity and well-aligned morphology in mixture of ethylene glycol and 0.3 wt% NH4F electrolyte at 40 V for 25 °C. The growth rates of TiO2 nanotube arrays can show activation energy.

TiO 2 nanotube arrays with an inner average pore diameter of 83 nm and a length of 14 μm are grown on Ti foils by electrochemical anodization in ammonium fluoride–water–glycerol solution. ZnO is introduced into the TiO 2 nanotube arrays by a convenient electrodeposition technique. ZnO/TiO 2 nanocomposites supported on Ti substrate are used as the photo-anode electrode for dye-sensitized solar cells (DSSCs). The morphology, structure and electrochemical properties are investigated using field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV–vis diffusion reflection spectroscopy, X-ray photoelectron spectroscopy and cyclic voltammetry measurements. It is found that ZnO have been embedded in the TiO 2 nanotube arrays, and changed some photoelectric properties. The conversion efficiency of the dye-sensitized solar cells is more than doubled, compared with that of bare TiO 2 nanotube arrays with deposited 60 min. This improvement comes from the synergetic effect between ZnO and TiO 2 , which increases dye absorption, electron transport and electron lifetime.

Water-based Polyaniline(PANI) emulsion and Fluorocarbon(FC) emulsion were synthesized by emulsion polymerization method. The doped polyanline were characterized by Transmission electron microscope(TEM) and X-ray diffraction(XRD). The results showed the PANI has bar-like shape and local crystallinity. The composite anticorrosion coatings of PANI emulsion and FC emulsion were prepared by mixture in aqueous medium and used for corrosion protection of mild steel. The corrosion protection property of PANI/FC coatings on mild steel was investigated by electrochemical impedance spectroscopy(EIS) and open circuit potential(OCP) technique in 3.5wt%NaCl aqueous solution. The results indicated that the water-based PANI/FC coatings could offer high protection because the impedance values and corrosion potential remained at higher. Scanning electron microscope(SEM) showed that the oxidation film formed on the metal surface and prevent corrosion effectively due to the passive effect of PANI pigment. The anticorrosion coatings are environmental friendly because of water dispersion medium.

Pt-counter electrodes were manufactured by dip coating, spin coating and sputtering methods for dye-sensitized solar cells (DSSCs). Their properties were analyzed with cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), energy disperse spectroscopy (EDS). We also fabricated the TiO2 nanotubes of 1.04 μm length as photoanode. The analytic results show that spin coating method has higher Pt content deposited on FTO glass, better performance of charge-transfer, more positive potential of tri-iodide reduction and higher efficiency of DSSCs.

Lithium niobate thin films have been deposited on Pt/Ti/SiO2/Si substrates by the Pechini method from metal carboxylate gels and heat-treated at temperatures ranging from 400 to 600°C. The thermal decomposition of the metal carboxylate precursor gels has been studied by differential thermal analysis and thermogravimetry. The products derived from calcination of the gels at different temperatures have been characterized by Fourier transform infrared, Roman spectrum and X-ray diffraction. Scanning electron microscopy analysis shows the surface of the films to be smooth, dense and crack-free. Electric properties measurement indicates that the LiNbO3 films demonstrate a ferroelectric hysteresis loop. The remanent polarization (Pr) and coercive field (Ec) are 17.89 μC/cm2 and 35.23 kV/cm, respectively.

Rare earth complex Eu(phen)2Cl3·2H2O synthesized by precipitation method was incorporated into MCM-41 mesoporous molecular sieves which were synthesized via a hydrothermal method. Hybrid inorganic/organic mesoporous luminescent material Eu(phen)2/MCM-41 has been characterized by XRD, TEM, IR, UV-visible spectra and fluorescence spectra. Results indicated that the hybrid mesoporous material has typical structure of MCM-41 and retains the same pore structure as MCM-41 after the assembly process. The fluorescence spectra of these materials present a series of narrow lines assigned to 5D0 → 7F0,1,2,3,4 transitions. The high emission intensity observed is a promising property for application of the rare earth complex in technological luminescent devices.

In this work, PZT (Zr/Ti=52/48) thin films have been prepared using aqueous organic gel method. The desired metal cations are chelated in a solution using citric acid and ethylenediaminetertraacetic acid (EDTA) as the chelating agents. The thermal decompostion of the metal carboxylate precursors gels have been studied by TG/DTA and the products derived from calcinations of the gels at different temperatures have been characterized by XRD and SEM. By heat-treatment at 650°C for 2h, PZT thin films with smooth and crack-free surface could be achieved. The thickness of each layer was 50nm. Electric properties measurement indicated that the PZT films demonstrated a ferroelectric hysteresis loop. The remanent polarization(Pr) and coercive field (Ec) were 20.7μC/cm2 and 75.5kV/cm, respectively. The dielectric constant and the dielectric loss at 100 kHz of the films were 930 and 0.045, respectively.

By adding methyl alcohol/water solution with certain concentration into sol to hydrolysis directly and sintering the fresh sol directly, lead titanate(PbTiO3) ceramics doped with magnesium are prepared by using magnesium acetate as doper to prohibit the disadvantages contained in conventional sol-gel method, such as low hydrolytic rate, high sintering temperature, long preparation period. The changes of structure, microstructure, synthesis process and electric properties of modified ceramics are studied in detail. The sizes and morphology of high purely and high density magnesium doped lead titanate nanocrystals thus obtained are observed by TEM photographs and the structures and affection of sintering temperature of to lattice constant and sizes of nanocrystals are detected by XRD. Electric properties detection results show that doped lead titanate ceramics exhibite excellent dielectric, ferroelectric and pyroelectric properties compare with pure lead titanate.

A supramolecular Cd(II) complex[Cd(bpdc) (phen)2 (H2O)] . 6H20 (1) was synthesized with 2, 4'-biphenyldicarboxylic acid (H2bpdc) and 1, 10-phenanthroline (phen) under hydrothermal conditions and characterized by single-crystal X-ray diffraction elemental analysis, and IR spectrum. Single-crystal X-ray analysis reveals complex 1 crystalizes in the triclinic P 1 space group, the metal center Cd(II) ion is six-coordinated and exhibits a distorted octahedron geometry arrangement. 3D supramolecular structure could be formed taking into account two kinds of hydrogen bonds and π--π interactions. At the same time, we discussed the luminescent properties of complex 1 in the solid-state as well as in the solvents at different temperatures. When excited at 350 nm, in the solid state at 298 K, 1 has purple luminescence with emission band at 390 nm; in the solid state at 77 K, 1 displays two emission bands at 380 and 520 nm. Because the vibration structure is more defined at low temperature, at 298 K, 1 also has purple luminescence in DMSO and CH3OH solutions with emission bands at 380 and 375 nm, which are blue-shifted compared with solid-state maximum emission band. These all can be attribute to the π*--π transition based on the coordinate ligands. The fluorescence decay curves of complex 1 indicate that the processes of decay consist of two components. At 298 K, the lifetime of 1 is longer in DMSO solution (τ1 =1. 73 µs and τ2 =14. 07 µs) than that in CH3OH solution (τ1 =1. 21 µs and τ2 = 12. 44 µs). Moreover, the-lifetime of 1 is longer at 77 K (τ1 =1. 96 µs and τ2= 16. 11 µs) than that at 298 K in the solid state (τ1= 1. 20 µs and τ2 =11. 34 µs). The results might be caused by the increase in radiative rate and decrease in non-radiative rate at low temperature.

Lithium niobate thin films have been deposited on Pt/Ti/SiO2/Si(100) substrates by Pechini method. Characterization of the initial precursor solutions containing citric acid (CA), niobium and lithium ions has been performed by Fourier transform infrared spectroscopy, Raman spectroscopy and carbon nuclear magnetic resonance spectroscopy. The results indicate that citric acid coordinate to niobium ions to form a niobium–CA complex through one terminal carboxyl group, the hydroxyl group and the central carboxyl group as a tridentate ligand. The thermal decomposition of the Li–Nb precursors gel powder has been studied and the results show that LiNbO3 phase is formed directly from the thermal decomposition of the precursor gel. By heat-treatment at 600 °C for 2 h, polycrystalline LiNbO3 thin films with smooth and crack-free surface could be achieved.

(PU/UP IPNs)-BaTiO3 nanocomposites with different amounts of BaTiO3 nanopowder are prepared and polarized. The ferroelectric and dielectric properties are detected and the relationship between electric properties and damping properties are discussed in detail. Results indicate that the synergistic effects can be created successfully by elastic damping of polymer, frictional damping of BaTiO3, and piezoelectric damping of nanocomposites after poling. The nanocomposites increase the damping property evidently and sustain mostly ferroelectric and dielectric characters of inorganic phase. The introduction of BaTiO3 into IPNs decreases the resistivity, and this has advantages to enlarge the damping loss factor (tanδ).

In present work, sol-gel process is used to direct the organization of high quality and pore-free parasite PZT thin films with a composition near the morphotropic phase boundary (Zr/Ti = 52/48). The PZT transparent sol can be obtained by dissolving the zirconium oxynitrate, butyl titanate and lead acetate in ethylene glycol with the molar ratio of 0.52:0.48:1 and the PZT gel can be gained by spin-coating. In such process, PZT thin films can be readily prepared by hydrolysis on hot plate at 350°C for 20min and annealing in RTA at 650°C for 1 minute. The structural and electric characteristics of the films have been carried out by XRD, AFM and the C-V measurements, etc. Experimental results have indicated that by treating film RTA at 6508 for 1 minute film with perfect crystallization and good surface morphology with a RMS roughness of 2.0nm can be obtained, and the remnant polarization Pr (28.5 μC/cm2) and coercive field Ec (39.8kV/cm) are obtained in the P-E hysteresis loops. The films have a dielectric constant ε of 1080 and a dielectric loss tanδ of 0.01 at 1 kHz. Ferroelectric polarization fatigue test of the films has shown that high fatigue resistance up to 3 × 1010 cycles before Pr is decreased by 50%.

Two rare 2D Ga/In-based coordination polymers in which one metal center coexists with three distinct aromatic ligands were synthesized. Helical channels along the 21 screw axis are exhibited to form a hcb net. The compounds exhibit tunable fluorescence from blue, green, white to yellow light by varying the temperature and solvents.