采用溶胶-凝胶法在氟掺杂氧化锡(fluorine-doped tin oxide,FTO)导电玻璃上制备Zn-Ti-O/FTO复合薄膜,并通过X射线衍射(X-ray diffraction,XRD)分析样品的物相结构,利用紫外可见(ultra-violet and visible,UV-Vis)分光光度计测试样品的...采用溶胶-凝胶法在氟掺杂氧化锡(fluorine-doped tin oxide,FTO)导电玻璃上制备Zn-Ti-O/FTO复合薄膜,并通过X射线衍射(X-ray diffraction,XRD)分析样品的物相结构,利用紫外可见(ultra-violet and visible,UV-Vis)分光光度计测试样品的吸收光谱,使用扫描电子显微镜(scanning electron microscope,SEM)表征样品的微观形貌.分别研究了Zn-Ti-O/FTO对甲基橙(methyl orange,MO)、亚甲基蓝(methylene blue,MB)以及罗丹明B(rhodamine B,RhB)的光催化降解作用.结果表明:所得到的Zn-Ti-O/FTO结构表现出明显的有机物降解的优选性,对于MB具有光催化降解效率为90.3%/(6 h)的最优降解效果.这种优选性可能与薄膜、衬底的导带底/价带顶以及有机降解物的最低未占分子轨道能级和最高占据分子轨道能级的相对位置相关.展开更多
Ba0.6Sr0.4TiO3 （BST） thin films with and without HfO 2 buffer layer were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. Dependences of HfO 2 thickness on the dielectric property and leakage curre...Ba0.6Sr0.4TiO3 （BST） thin films with and without HfO 2 buffer layer were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. Dependences of HfO 2 thickness on the dielectric property and leakage current of BST thin films were focused. The dielectric constant of BST thin films increased and then decreased with the increase of HfO 2 thickness, while the dielectric relaxation was gradually improved. The loss tangent and leakage current under positive bias decreased with the HfO 2 thickness increasing. The leakage current analysis based on the Schottky emission indicated an improvement of the BST/Pt interface with HfO 2 buffer layer. The loss tangent, tunability and figure of merit of optimized HfO 2 buffered BST thin film achieved 0.009 8, 21.91% （E max = 200 kV/cm）, 22.40 at 10 6 Hz, respectively.展开更多
BiFeO3 (BFO) thin films were prepared on Pt(111)/TiO2/SiO2/Si(100) substrates by the pulsed-laser deposition (PLD) technique at a low temperature of 450℃. The XRD results indicate that the BFO thin films are of perov...BiFeO3 (BFO) thin films were prepared on Pt(111)/TiO2/SiO2/Si(100) substrates by the pulsed-laser deposition (PLD) technique at a low temperature of 450℃. The XRD results indicate that the BFO thin films are of perovskite structure with the presence of small amount of second phases. The oxygen pressures have great effect on the crystalline structures and dielectric properties of BFO thin films. The dielectric constant of the BFO thin films decreases with increasing oxygen pressures, achieving 186, 171 and 160 at the frequency of 104 Hz for the oxygen pressures of 0.666, 1.333 and 13.332 Pa, respectively. The BFO thin films prepared at the oxygen pressure of 0.666 Pa reveal a saturated hysteresis loop with the remanent polarization of 7.5 μC/cm2 and the coercive field of 176 kV/cm.展开更多
BiFeO3-PbTiO3 (BFO-PT) thin films were prepared on Pt/TiO2/SiO2/Si substrates by pulsed-laser deposition (PLD) technique under different oxygen pressures. The structures of the films were characterized by means of XRD...BiFeO3-PbTiO3 (BFO-PT) thin films were prepared on Pt/TiO2/SiO2/Si substrates by pulsed-laser deposition (PLD) technique under different oxygen pressures. The structures of the films were characterized by means of XRD. The current densities were performed to check the conductivity of the films. The dielectric constant and loss factor (tanδ) of the films were measured. The results show that the BFO-PT layers are mainly perovskite structured; the film deposited under 6.665 Pa exhibits low leakage current, low dielectric loss (0.017-0.041) and saturated hysteresis loop with polarization (Pr) value and coercive field (Ec) of 3 μC/cm2 and 109 kV/cm.展开更多
文摘采用溶胶-凝胶法在氟掺杂氧化锡(fluorine-doped tin oxide,FTO)导电玻璃上制备Zn-Ti-O/FTO复合薄膜,并通过X射线衍射(X-ray diffraction,XRD)分析样品的物相结构,利用紫外可见(ultra-violet and visible,UV-Vis)分光光度计测试样品的吸收光谱,使用扫描电子显微镜(scanning electron microscope,SEM)表征样品的微观形貌.分别研究了Zn-Ti-O/FTO对甲基橙(methyl orange,MO)、亚甲基蓝(methylene blue,MB)以及罗丹明B(rhodamine B,RhB)的光催化降解作用.结果表明:所得到的Zn-Ti-O/FTO结构表现出明显的有机物降解的优选性,对于MB具有光催化降解效率为90.3%/(6 h)的最优降解效果.这种优选性可能与薄膜、衬底的导带底/价带顶以及有机降解物的最低未占分子轨道能级和最高占据分子轨道能级的相对位置相关.
基金Project supported by the Foundation of the Education Commission of Shanghai Municipality (Grant Nos.07ZZ14, 08SG41)the National Natural Science Foundation of China (Grant No.50711130241)the Shanghai Rising Star Program (GrantNo.08QH14008)
文摘Ba0.6Sr0.4TiO3 （BST） thin films with and without HfO 2 buffer layer were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. Dependences of HfO 2 thickness on the dielectric property and leakage current of BST thin films were focused. The dielectric constant of BST thin films increased and then decreased with the increase of HfO 2 thickness, while the dielectric relaxation was gradually improved. The loss tangent and leakage current under positive bias decreased with the HfO 2 thickness increasing. The leakage current analysis based on the Schottky emission indicated an improvement of the BST/Pt interface with HfO 2 buffer layer. The loss tangent, tunability and figure of merit of optimized HfO 2 buffered BST thin film achieved 0.009 8, 21.91% （E max = 200 kV/cm）, 22.40 at 10 6 Hz, respectively.
基金Project (50472098) supported by the National Natural Science Foundation of China
文摘BiFeO3 (BFO) thin films were prepared on Pt(111)/TiO2/SiO2/Si(100) substrates by the pulsed-laser deposition (PLD) technique at a low temperature of 450℃. The XRD results indicate that the BFO thin films are of perovskite structure with the presence of small amount of second phases. The oxygen pressures have great effect on the crystalline structures and dielectric properties of BFO thin films. The dielectric constant of the BFO thin films decreases with increasing oxygen pressures, achieving 186, 171 and 160 at the frequency of 104 Hz for the oxygen pressures of 0.666, 1.333 and 13.332 Pa, respectively. The BFO thin films prepared at the oxygen pressure of 0.666 Pa reveal a saturated hysteresis loop with the remanent polarization of 7.5 μC/cm2 and the coercive field of 176 kV/cm.
基金Project(04A1B18) supported by Shanghai Municipal Education Commission Project(50472098) supported by the National Natural Science Foundation of China Project(04qmx1440) supported by Shanghai Rising Star Program, China
文摘BiFeO3-PbTiO3 (BFO-PT) thin films were prepared on Pt/TiO2/SiO2/Si substrates by pulsed-laser deposition (PLD) technique under different oxygen pressures. The structures of the films were characterized by means of XRD. The current densities were performed to check the conductivity of the films. The dielectric constant and loss factor (tanδ) of the films were measured. The results show that the BFO-PT layers are mainly perovskite structured; the film deposited under 6.665 Pa exhibits low leakage current, low dielectric loss (0.017-0.041) and saturated hysteresis loop with polarization (Pr) value and coercive field (Ec) of 3 μC/cm2 and 109 kV/cm.
