Yuzhi Zhang

Preparation and electrochromic properties of Li-doped MoO3 films fabricated by the peroxo sol-gel process

Abstract Molybdenum oxide (MoO 3 ) films were prepared by the sol–gel process, using a lithium-doped peroxo-polymolybdate precursor solution. The highest quality films were obtained from precursor solutions containing 10% lithium. The structural properties of the films were characterized by TG-DTA and FTIR. The electrochemical and electrochromic properties were measured by cyclic voltammetry and an in-situ transmittance technique in 1 M LiClO 4 /propylene carbonate electrolyte. The results show that the Li-doped MoO 3 films possess excellent electrochemical stability and reversibility, a remarkable change of transmittance (Δ T =32.3%) in visible region after coloration, and good electrochromic performance.

Structural, morphological and electrochromic properties of Nb2O5 films deposited by reactive sputtering

Abstract Nb 2 O 5 films were prepared successfully by DC reactive sputtering process. The relationships among structural, morphological and electrochromic properties were studied using XRD, AFM, AES and cyclic voltammograms. Results show that the films deposited on heated substrates are composed of columnar TT-Nb 2 O 5 microcrystalline with many grain-to-grain boundaries. These structural characteristics provide films strong electrochemical stability, high Li + insertion/extraction reversibility and good electrochromic properties. DC reactive sputtered Nb 2 O 5 films are colorless in bleached state and brownish gray in colored state and may be a promising candidate for the application in electrochromic devices.

Study on Raman spectra of electrochromic c-WO3 films and their infrared emittance modulation characteristics

Abstract Polycrystalline tungsten oxide films with good electrochemical stability were prepared by dc reactive sputtering method. The Raman spectra of these films show that the W 6+ ions were reduced to W 5+ with the co-intercalation of Li + ions and electrons. Intercalated electrons entered extended states of crystalline tungsten oxide and caused infrared reflectance variation, therefore, the emissivity of WO 3 /ITO/glass can be reversible modulated between 0.261 and 0.589.

Preparation of silicon carbide nitride thin films by sputtering of silicon nitride target

Amorphous silicon carbide nitride thin films were synthesized on single crystal silicon (0 0 1) substrates by rf reactive sputtered a silicon nitride target in methane and argon atmosphere. The effects of sputtering parameters such as target voltage in the range of 1.6‐3.0 kV on the optical properties were studied by a Cary 500 UN-VIS-NIR spectrophotometer and Bio-Rad FTS 185 FTIR spectrometer. The results showed that the deposition rate reached maximal at the target voltage of 2.5 kV. The refractive index, n, decrease with increase of target voltage except the sample deposited on 1.6 kV. Moreover, the maximal proportion of Si‐C and C‐N bond achieved at the target voltage of 2.5 and 2.0 kV, respectively. It reflects that the bonding configuration can be tailored by adjusting the target voltage. # 2001 Published by Elsevier Science B.V.

Dynamic compression properties of porous aluminum

The dynamic compression properties of porous aluminum with nearly constant relative density and four different pore sizes were studied and compared with its quasi-static compression properties. It is found that at the same strain rate, all the quasi-static and dynamic compression properties are essentially independent of pore size; while for the same pore size, the flow stress at dynamic compression is much higher than that at quasi-static compression. The results are interpreted in the light of the simple cubic cell model.