气敏元件室温光激发气敏性能研究

研究了WO3掺杂的ZnO基气敏元件在紫外(UV)光激发下,对乙醇气体的室温气敏性能。结果表明:在UV光照射下,各元件在室温下对体积分数为100×10–6的乙醇气体显示了很好的光敏、气敏性能,响应、恢复时间均在8s以内,其中以掺杂X(WO3)为1%的元件W(1)为最佳,从而实现了室温下的气敏测试。     

The effects of CO,water vapor and surface temperature on the conductivity of a SnO2 gas sensor

It is shown that the conductivity of a SnO₂ gas sensor depends on the concentration of CO and H₂O in the atmosphere n which it is placed. The experimental data can be explained in a consistent manner by hypothesizing that 1) adsorbed oxygen depletes the surface electron concentration and therefore decreases the conductivity; 2) adsorbed water causes electrons to accumulate at the surface and therefore increases the conductivity; 3) CO increases the conductivity by removing adsorbed oxygen by reacting with it to form CO₂; and 4) adsorbed water catalyzes the CO to CO₂ reaction.     

Effects of graphite on the synthesis of 1-D single crystal In2O3 nanostructures at high temperature

This study investigated the effects of graphite powder on the growth mechanisms of one-dimensional (1-D) single-crystal indium oxide (In₂O₃) nanostructures. The study was conducted using a chemical vapor deposition (CVD) method at 1000 °C; In₂O₃ and graphite powder mixed with In₂O₃, with a weight ratio of 1:1, were used as the source material, while 2 nm-thick n-type silicon (100), coated with a gold catalyst, was used as a substrate. It was observed that nanostructures grew via a Vapor-Liquid-Solid (VLS) growth mechanism when only In₂O₃ was used, but grew via both VLS and Vapor-Solid (VS) growth mechanisms when graphite powder was used with the In₂O₃. The morphology and crystal structures of the nanostructures grown were investigated using X-Ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HR-TEM), Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersion X-Ray Spectroscopy (EDS). At room temperature (RT), all the nanostructures showed photoluminescence (PL) spectra at a wavelength of 367 nm in the UV-emission region and at wavelengths of 470 and 630 nm in the visible region.     

溅射压强对柔性PET衬底ZnO薄膜性能的影响

利用直流磁控溅射法,在室温水冷柔性PET衬底上成功制备出了掺钛氧化锌(ZnO:Ti,TZO)透明导电薄膜。通过X射线衍射(XRD)研究了薄膜的结构,用扫描电镜(SEM)研究了薄膜的表面形貌,用四探针和紫外-可见分光光度计等仪器对薄膜的特性进行测试分析,研究了溅射压强对ZnO:Ti薄膜表面结构、形貌、力学、电学和光学性能的影响。结果表明,溅射压强对PET衬底上的TZO薄膜的性能有显著的影响,实验制备的ZnO:Ti薄膜为具有C轴择优取向的六角纤锌矿结构的多晶薄膜;当溅射压强从2Pa增加到4Pa时,薄膜的电阻率由10.87×10-4Ω.cm快速减小到4.72×10-4Ω.cm,随着溅射压强由4Pa继续增大到6Pa,薄膜的电阻率变化平缓,溅射压强为5Pa时薄膜的电阻率最小,为4.21×10-4Ω.cm;经计算得到6Pa时样品薄膜应力最小,为0.785 839GPa;所有样品都具有高于91%的可见光区平均透过率。