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Gradient Si-rich carbide (GSRC) thin films were deposited on monocrystalline silicon wafers and quartz substrates by magnetron co-sputtering, with subsequent thermal annealing by rapid thermal processing. Fourier transform infrared spectroscopy, Raman spectroscopy, grazing incident X-ray diffraction, transmission electron microscope, and Hall measurements were used to analyze the microstructure and conductivity of the films. It was observed that bonding configurations, microstructure and conductivity properties changes with the annealing temperature from 700°C to 1000°C. The experimental results demonstrate that Si QDs with crystal volume fraction of 72.5%, average size of 4.5 nm, and number density of ~2 ×10¹²cm^-2 embedded in the amorphous SiC matrix can be formed using a GSRC multilayer structure, with subsequent annealing at 1000°C. The 1000°C annealed thin film possesses a conductivity of ~5 S ⋅ cm^-1, which can be attributed to high carrier transport efficiency caused by high Si QD density.

The SOFC interconnect materials La${}_{0.75}$Sr${}_{0.25}$Cr${}_{1-x}$O${}_{3-\delta }$$(x=0$–$0.04)$ were prepared using an auto-ignition process. The influences of Cr deficiency on their sintering, thermal expansion and electrical properties were investigated. All the samples were pure perovskite phase after sintering at 1400${}^{\circ }$C for 4 h. The cell volume of La${}_{0.75}$Sr${}_{0.25}$Cr${}_{1-x}$O${}_{3-\delta }$ decreased with increasing Cr deficient content. The relative density of the sintered bulk samples increased from 93.2% $(x=0)$ to a maximum value of 94.7% $(x=0.02)$ and then decreased to 87.7% $(x=0.04)$. The thermal expansion coefficients of the sintered bulk samples were in the range of $10.60$–$10.98\times 10^{-6}{\mathrm{\text{K}}}^{-1}$ (30–1000${}^{\circ }$C), which are compatible with that of YSZ. Among the investigated samples, the sample with 0.02 Cr deficiency had a maximum conductivity of 40.4 Scm${}^{-1}$ and the lowest Seebeck coefficient of 154.8 $\mu$VK${}^{-1}$ at 850${}^{\circ }$C in pure He. The experimental results indicate that La${}_{0.75}$Sr${}_{0.25}$Cr${}_{0.98}$O${}_{3-\delta }$ has the best properties and is much suitable for SOFC interconnect material application.

${\mathrm{\text{Sr}}}_{1-3x/2}{\mathrm{\text{La}}}_x{\mathrm{\text{TiO}}}_3$ (SLTO) ceramics ($x$ = 0.05, 0.10, 0.15) were prepared with giant dielectric constant by the traditional solid-state method at 1350${}^{\circ }$C. The temperature dependence of the dielectric constant was obtained at the temperature ranging from 29${}^{\circ }$C to 500${}^{\circ }$C and the frequency ranging from 2 kHz to 2 MHz. Two sets of relaxation peaks appear in the low temperature (region I) and the high temperature (region II), respectively. For region I, we conclude that the relaxation behavior is related to the oxygen vacancy migration. For region II, the two relaxation processes are caused by grain boundary for high frequency and Sr or Ti defects at grain interior for low frequency. With the doping amount reaching 0.15, the relaxation peaks disappear and become a common phase transition because of the aggravation of lattice distortion. These possible physical mechanisms of two sets of relaxation peaks are briefly discussed.

The intrinsic point defect influence data for $\beta$–Si₃N₄ by far are incomplete and experimental clarification is not easy. In this contribution, the effects of vacancy (${\mathrm{\text{V}}}_{\mathrm{\text{2c}}}$, ${\mathrm{\text{V}}}_{\mathrm{\text{6h}}}$ and ${\mathrm{\text{V}}}_{\mathrm{\text{Si}}}$) and interstitial (${\mathrm{\text{I}}}_{\mathrm{\text{N}}}$ and ${\mathrm{\text{I}}}_{\mathrm{\text{Si}}}$) defects on the electronic properties of H-passivated $\beta$–Si₃N₄ (0001) surface are explored based on density functional theory (DFT) calculation. The results show that it is easier to form ${\mathrm{\text{N}}}_{\mathrm{\text{6h}}}$ vacancy defects in the surface layer under Si-rich conditions. The existence of N vacancies makes the bottom of conduction bands shift downwards, and the top of valance band is away from Fermi level. The presence of ${\mathrm{\text{V}}}_{\mathrm{\text{Si}}}$ makes the system have the characteristics of p-type semiconductor, and the closer to the inner layer, the narrower the range of additional energy bands and the greater the degree of localization of electrons. The closer the Si atom vacancy is to the surface, the smaller the photon energy corresponding to the maximum absorption coefficient is. Compared with the N vacancy system, the Si vacancy system has higher reflection ability in the low energy region. For the interstitial defect systems, ${\mathrm{\text{I}}}_{\mathrm{\text{N}}}$ is easy to form on the surface layer, and ${\mathrm{\text{I}}}_{\mathrm{\text{Si}}}$ is easy to produce in the inner layer. The ${\mathrm{\text{I}}}_{\mathrm{\text{N}}}$ system has a new additional energy level at the Fermi level, and as the ${\mathrm{\text{I}}}_{\mathrm{\text{N}}}$ is closer to the inner layer, the energy range of the additional energy level is also narrower. In the ${\mathrm{\text{I}}}_{\mathrm{\text{Si}}}$ system, the new additional energy levels appear at the Fermi level and the intermediate band. The results have positive significance for the design of this advanced structural and functional integrated ceramics. The absorption coefficient and reflection coefficient of ${\mathrm{\text{I}}}_{\mathrm{\text{Si}}\text{-}3}$ system are much higher than those of other systems when the energy is greater than 2.5 eV.

A series of Zn_1-xMg_xO(x = 0 ~ 0.16) films have been prepared on glass substrates by RF magnetron sputtering. The structure, surface morphology, composition, optical and electrical properties of the films were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), Raman spectroscopy, UV-Vis spectrophotometer and Hall measurement, respectively. It reveals that the obtained films are uniform hexagonal wurtzite polycrystalline with grain size about 100 nm.The optical transmittance are over 80% and the band gap (Eg) has linear relationship with Mg content: Eg = 1.67x + 3.274 (eV) (0 < x < 0.16). The resistivity of the films increases with the increase of Mg content. The Raman spectra of the films show that the position of E₂ peaks (473 cm^-1) has not changed, but the A₁(LO) mode (577 cm^-1) frequency shifts to lower wavenumbers with the increase of Mg content, indicating that Mg-doping does not cause intensive lattice deformation, but results in the decrease of the carrier concentration, which is corresponding to the degradation of the conductivity of ZnMgO films with the increase of Mg content.

Oxygen-deficient zinc oxides thin films with different levels of defects were prepared by using radio frequency magnetron sputtering method with sintered zinc oxide disk as target at different sputtering powers. The composition, structure and electrical properties of the prepared films were investigated. Under the present conditions, all the obtained films possessed würtzite structure, which were growing preferentially along the $c$-axis. The thickness of the films, the size of the zinc oxide grains and the content of Zn atoms increased with increasing sputtering power. In the films deposited at a sputtering power from 52W to 212W, the main defect was interstitial zinc. With increasing sputtering power, due to the enhanced number of interstitial zinc in the films, their room-temperature electrical resistivity would decrease, which was controlled by electron conduction. At increasing measurement temperature, their electrical resistivity would increase, owing to the decrease of defect concentration caused by oxidization.

In-substituted BaSnO₃ (BaSn_1-xIn_xO_3-δ, x = 0.125, 0.25 and 0.50) compounds were prepared by a gel polymerization method. Their microstructure, hydration energy and electrical properties were investigated. Single phases were confirmed by X-ray diffraction analysis over the whole range of substitution, and were identified as cubic perovskite-like structure. The grain size and conductivities of samples measured under dry and wet atmospheres increase significantly with indium content as such, 1–2 μm for BaSn_0.875In_0.125O_3-δ(x = 0.125) and 20 μm for BaSn_0.50In_0.50O_3-δ(x = 0.50). The highest proton conductivity at 600°C, σ = 9.5 × 10^-4 S⋅cm^-1, is obtained for BaSn_0.5In_0.5O_2.75(x = 0.50).

Phase diagrams of BiFeO₃-BaTiO₃ (BF–BT) thin films were constructed via thermodynamic model calculation, as well as their electrical properties. The calculated morphotropic phase boundary (MPB) of BF–BT thin films without strain is located near the composition of 0.663BF–0.337BT, which agrees well with the experimental results of reported BF–BT ceramics (between 0.66BF–0.34BT and 0.71BF–0.29BT). The permittivity, tunability and $d_{33}$of BF–BT thin films on Si substrates are higher than those on SrTiO₃(ST) plates, which are also in accordance with the measured data in the literature. Further calculation indicates that 0.7BF–0.3BT and 0.6BF–0.4BT thin films can achieve enormous piezoelectric coefficient $d_{33}$ ($\sim$1200 and $\sim$1000 pm/V, respectively) by selecting the substrates with the TEC respectively of 0.3 and 3.1 × 10${}^{-6}$/${}^{\circ }$C, because of the phase transition from aa phase to rhombohedral phase. Such results help to clarify the phase diagrams of BF–BT thin films, implying that huge $d_{33}$can be achieved by choosing the composition near MPB on the substrates with small TEC.

The orthogonal perovskite EuFe_0.9Co_0.1O₃ oxides with uniform particle size distribution were prepared by a sol–gel method. The samples were calcined at the different temperatures and the results showed that the mean grain size increased from 31 to 38 nm when the calcinations temperature increased from 600 to 900 °C. The investigation of sensing properties exhibited that the sensor based on EuFe_0.9Co_0.1O₃ calcined at 800 °C has good gas sensing properties to acetone gas at the operating temperature of 280 °C.

In this paper, the effects of carbon fiber and steel slag on the electrical properties at different ages have been studied. The structures were characterized by SEM. The experimental results show that with the increasing of carbon fiber, fibers tend to lap over each other, result in the formation of the conductive channel. When the content of carbon fiber is more than 0.5%, the amount of carbon fiber is not the main factor affecting the change of resistivity, resistivity of cement mortar is obviously weakened. When the content of steel slag is low, conductive phases can not be contacted with each other, addition of steel slag and carbon fiber can not reduce the resistivity significantly. With the increasing of steel slag, the distance between conductive materials is nearer, the conductive function of carbon fiber and ferric oxide in steel slag is enhanced, the electron and the hole is conducted by means of the tunnel effect, at this time, the resistivity of cement based composites decreased rapidly, the steel slag contact with each other, forming a conductive network.

Cu₂(Sn_1-xMg_x)Se₃ (Mg-x-CTSe) bulks at x = 0, 0.05, 0.1, 0.15, and 0.2 were prepared at 550 °C for 2 h. Defect chemistry was studied by measuring structural and electrical properties of Mg-doped Cu₂SnSe₃ as a function of the dopant concentration. Mg-x-CTSe pellets were p-type at x = 0, 0.05, and 0.1 and n-type at x = 0.15 and 0.2. The low hole concentration of 3.18×10¹⁷ cm^-3, high mobility of 387 cm² V^-1 s^-1, and low conduction of 20 S cm^-1 were obtained for Cu₂(Sn_1-xMg_x)Se₃ bulks at x = 0.1 (5% Mg), as compared to 1.06×10¹⁸ cm^-3, 209 cm² V^-1 s^-1, and 36 S cm^-1 for undoped one. The explanation based upon the Mg-to-Sn antisite defect for the changes in electrical properties was declared.