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As anode-support materials for solid oxide fuel cells, porous LaNbO4–NiO–Y2O3 stabilized ZrO2 (YSZ) composites (LNY), containing 0, 5, 10, 15, and 20 wt% of LaNbO4 and designated as 0LNO, 5LNO, 10LNO, 15LNO, and 20LNO, respectively, are prepared by tape casting and sintering. They are investigated for their microstructure and mechanical, electrical and thermal expansion properties. The porosity of as-sintered LNY is around 30%, and that of reduced LNY cermets decreases from 47% for reduced 0LNO to 43% for reduced 20LNO. The fracture strength (σf) of LNY is higher than that of the reduced form; however, both of them are not rather sensitive to the amount of LaNbO4, depending on crack-originating flaws in the specimens. The fracture toughness (KIC) of LNY increases with LaNbO4 content and is 1.87 MPa·m1/2 for 20LNO, which is more than 20% increase from that of 0LNO; however the KIC for reduced LNY is higher than that of LNY, and decreases with increasing LaNbO4 content due to the decreased amount of ductile metallic Ni phase. The conductivity of reduced LNY depends on Ni content and is higher than 289 S/cm at temperatures below 900°C. The coefficient of thermal expansion (CTE) of both LNY and reduced LNY is in the range between 12.4 and 11.4 × 10−6 K−1; which is closely matched with that of YSZ electrolyte.

The homogeneously deposition of quantum dots (QDs) on the mesoporous or one-dimensional TiO2 film with a well-covered layer has become one major challenge in quantum dot-sensitized solar cell (QDSSC). In this study, one-dimensional TiO2 nanorod arrays based photoanode prepared by a simple linker-assisted SILAR method is studied. The influence of the short organic ligand (TGA) on the homogeneity of QDs on TiO2 nanorod arrays is discussed and the photoelectrochemical performance of QDSSC is evaluated by UV–vis absorbance spectroscopy, current–voltage performance and electrochemical impedance spectroscopy. The results show that the TGA ligand can act as an efficient bridge between CdS QDs and TiO2, whereas the content and particle size of the QDs can be easily tuned by controlling the dipping time and SILAR cycle. Owing to the presence of TGA, the charge-transfer rate at CdS QDs and TiO2 interfacial region is noticeable enhanced.

Here, we report a novel double-layer structure photoanode with TiO2 nanotube (TNT) layer and TiO2 nanoparticle (TP) layer via a two-step method of electrochemical anodization and screen printing for dye-sensitized solar cells (DSSCs). The results indicate that DSSCs with this double-layer structure have significant advantages of large surface area, long electron lifetime, superior electron recombination restraint characteristics, and high light scattering. The layer thickness of nanotubes and nanoparticles is also investigated and finally an optimized double-layer structure with excellent performance is prepared. With such a double-layer structure photoanode, DSSC with a relative high conversion efficiency of 6.43% and a short-circuit photocurrent density of 16.40 mA·cm−2 is obtained.

Photoanodes for flexible DSSC have been prepared through a chemical sintering method using hydrothermal cement at low temperature of 120 degrees C. The addition of the hydrothermal cement can effectively increase the adhesion between the photoanode and flexible ITO-PET substrate and build the interconnection between nanoparticles at low temperature for the fast transport of electrons. The flexible DSSC based on the photoanode obtains a relatively high photo-to-electric conversion efficiency of 4.0%. The method basing on the commercially available TiO2 with a small proportion of hydrothermal cement is suitable for roll-to-roll screen-printing preparation, which is expected to be scaled up for mass production of high performance flexible DSSCs.

The single crystal NiAl2O4 was prepared by a solid-state reaction. The change of its cation distribution with temperature was calculated by a modified thermodynamic equation by including a new parameter δ, which is a characteristic of nonconfiguration entropy. The calculated results showed that the degree of inversion for NiAl2O4 decreases with temperature, although the temperature dependence of cation distribution is very weak. This result was supported by X-ray diffraction measurement.

Nickel aluminate spinels were prepared by solid-state reaction. Their lattice parameters (a 0 ) changed with preparation temperature, which was explained by cation distribution, vacancies formation, and cation entrance. When the preparation temperature increased from 1100° to 1200°C, a 0 decreased with temperature as the result of the uptake of Al 2 O 3 . After 1200°C, a 0 increased to temperature, which was attributed to some Ni 2+ exchange with tetrahedral sites and some vacancies occupancy by Ni 2+ and Al 3+ .