Advanced Materials Research Vol. 465

Abstract: Indium tin oxide (ITO) films were deposited on glass substrates by using the homemade spray pyrolysis system. Orthogonal test was designed to examine the optimal conditions for preparation of the ITO films. The results showed that the ITO thin films can be prepared by the homemade spray pyrolysis device successfully. The device is simple in structure and easy to use. The substrate temperature is the main factor on the photoelectric properties of the ITO films. The optimal conditions for preparing the ITO thin films were as following: the substrate temperature is 300oC, the carrier gas flow of the air was 1.5 L•min-1, the annealing temperature was 500oC, the proportion of the indium and tin was 10:1, the distance between substrate and nozzle was 8 cm, and the deposition time was 3.5 min. The average optical transmittance in the visible range and sheet resistance of the ITO film were 93% and 2786Ω/□, respectively.

Abstract: Pt nanoparticles were successfully assembled in self-organized TiO₂ nanotubes by a chemical deposition method. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used for characterizing the surface morphology and phase composition. Photocurrent response activity was measured. Different morphology of Pt-TiO₂ NTs exhibited different photocurrent generation efficiency. High density Pt nanoparticles depositing on TiO₂ NTs decreased the photocurrent of Pt-TiO₂ electrodes. It was because the high density Pt nanoparticles could become the recombination centers of photoelectrons and holes.

Abstract: Me/MeN/Me (Me=Al, Ti ) multilayer thin films were deposited on silicon substrates by a multi-arc ion plating method (MAIP) and successive magnetron sputtering method (MS) respectively. The as-prepared and heat-treated films were characterized by scanning electron microscope (SEM) and auger electron spectra (AES). The results revealed that MS method has an advantage over MAIP method to prepare the Al/AlN/Ti submicron thin films which have high density, clear interface and smooth surface. In addition, the present study indicated that both the deposition sequence and mid-layer composition have a significant effect on the thermal stability. After heat-treatment at 500 oC for 10 min, the Al/AlN/Ti multilayer film prepared by the MS method has good thermal stability without surface crack or surface flaking. Furthermore, significant diffusion of oxygen element and nitrogen element within the multilayer interface was observed by the AES measurement. It is believed that the element diffusion in the multilayer interface plays an important role in the binding strength of multilayer interface.

Abstract: It is very hard to fabricate nano-strctures on PEDOT:PSS film by conventional Nanoimprint Lithography for its non-thermoplastic property. Here we demonstrated a new nanoimprint process to pattern the PEDOT:PSS film at low temperature and low pressure by adding proper amount of Glycerol into PEDOT:PSS solution and pressing the Si-mold into Glycerol-PEDOT:PSS film under a pressure of 6.2Mpa for 45min at 80°C. We also compared our result to L. Tan and co-workers’. They found that positive replica was left on PEDOT:PSS film after pressing the Si-mold into Glycerol-PEDOT:PSS film under a pressure of 10Kpa for 5min at 80°C, but our work showed negative replica formed. Pressing time maybe is the critical reason to explain the different results. Holding the pressure longer gave the PEDOT:PSS enough time to flow into Si-mold and also gave Glycerol enough time to evaporate so that PEDOT:PSS became strong enough when separated the Si-mold from the PEDOT:PSS film. At last, Roman spectra was measured to confirm adding glycerol to PEDOT:PSS will not influence its molecular structure.

Abstract: Abstract. Ca3CO4O9/x wt.%SiO2 composites were prepared by using field-activated pressure-assisted synthesis(FAPAS) process. The effects of nano-SiO2 addition on the microstructure and thermoelectric properties of the Ca3CO4O9 were investigated. With an increasing of the of SiO2 content, the size of Ca3Co4O9 particles decreased. The Seebeck coefficient decreased after the doping of nano-SiO2. The electrical conductivity firstly increased and then decreased with increasing amount of nano-SiO2 and the highest value belong to the Ca3CO4O9/0.5 wt.% SiO2 - sample. With the highest electric conductivity and slightly decreased Seebeck coefficient, the Ca3CO4O9/0.5 wt.%SiO2-sample achieved the highest power factor of 0.349 mw/mk2 at 800 °C, which is 8% higher than the value of pure Ca3CO4O9 reported in the literature.

Abstract: The weak-light characteristics of the GaAs/InGaAs quantum effect photoelectric sensor are presented. In order to explore its higher sensitive application because of higher quantum efficiency, a readout integrated circuit (ROIC) of the capacitor feedback transimpendance amplifier (CTIA) was designed to deal with voltage response of novel sensor. The readout circuit integration was designed to match 2×8 the photoelectric sensor array. A 633nm laser beam shot to the window of sensor with radiation intensity 2nW the readout response voltage was 225mV and 4.5E +07V /W responsivity at 120K and 44.8μs integration time when biased voltage up to -3V. Even under 0.5nw shooting,we still can see the high sensitivity.