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To optimize the process and obtain highly conducting and transparent Aluminum-doped zinc oxide (AZO) thin films, AZO films were deposited on glass substrates at room temperature by Radio-frequency (RF) magnetron sputtering with various Argon flow rates. The influences of Argon flow rate on structure, morphology, optical, electrical and photoluminescence properties of AZO films were investigated by varying the Argon flow rate from 36 to 68 sccm. The best quality AZO film with resistivity 1.39 × 10−3 Ω cm, sheet resistance 8.2 Ω/sq and 84.2% average visible transmittance was prepared at 44 sccm for 30 min. Also, the self-heating effect of target was investigated by preparing AZO films for 10 min and 20 min at 44 sccm, 180 W and 1.0 Pa. The influence of increasing structural quality actually affected by Argon flow rate was more prominent on carrier concentration than mobility. The schematic illustration of microstructural evolution was proposed. The average growth rate of around 60 nm/min demonstrated the self-heating effect of target was weak and could be ignored.

In this paper, the morphological and optical properties of LTO/TaOx composite structure films and electrochromic properties of “ITO/NiOx/LTO/TaOx/WOx/ITO” electrochromic devices (ECDs) based on LTO/TaOx composite structure films are reported. The composite films are deposited on the ITO substrate by reactive magnetron sputtering. The results of XRD, SEM, and AFM show that LTO film is amorphous and the performance of films prepared by sputtering power of 100 W for 5 h is the best. The optical transmittance of the multilayer structure is tested using an ultraviolet-visible spectrum and the refractive index dispersion is calculated using the relationship between the peaks in the spectrum based on equal inclination interference theory. Optical transmittance and refractive index dispersion are changed with the increase of magnetron sputtering power. Electrochromic tests show that all-solid-state ECDs based on composite films have 13 s coloring and 14 s fading response time, and the average optical modulation amplitude is 58%.

In this study, negative temperature coefficient (NTC) ceramics based on CaCu3Ti4-xZrxO12(0 ≦ x ≦ 0.15) compositions have been successfully synthesized by traditional solid-state method. X-ray diffraction results show that the major phase of all samples is CaCu3Ti4O12 (CCTO) phase with body-centered cubic structure. The substitution of Zr4+ for Ti4+ inhibits the grain growth of CaCu3Ti4-xZrxO12 ceramics and greatly reduces the grain size. The results of X-ray photoelectron spectroscopy fully confirm the coexistence of Cu+/Cu2+ and Ti3+/Ti4+ ions, which are one of the important reasons for conductivity of CaCu3Ti4-xZrxO12 samples. There is a good linear relationship between the natural logarithm of resistivity and reciprocal temperature of all ceramic samples, which is consistent with NTC behavior. The obtained values of ρ150, B150/550 and Ea of the sintered samples are in the range of 1.62 × 105–3.39 × 105 Ω cm, 6378–6593 K and 0.550–0.568 eV, respectively.

We synthesize MAl12O19 (M = Ca, Sr, Ba) singly doped with Eu2+ or Cr3+ and co-doped with Eu2+ and Cr3+ by high-temperature solid-state reaction under reducing atmosphere. It is observed that there exit energy transfers from Eu2+ to Cr3+ in MAl12O19 (M = Ca, Sr, Ba) hosts. Although the MAl12O19 (M= Ca, Sr, Ba) hosts have similar crystal structures, the energy transfer efficienies and the conversion rates of the blue light to the red light are different. Both experiment and calculation show that the energy transfer from Eu to Cr in CaAl12O19 host is most efficient, and the ratio of the red emission to the blue emission in CaAl12O19 host is the highest among the three different hosts.