TiO2 films have been widely applied in photo- voltaic conversion techniques. TiO2 nanotube arrays (TiO2 NAs) can be grown directly on the surface of metal Ti by the anodic oxidation method. Bi2S3 and PbS nanoparticl...TiO2 films have been widely applied in photo- voltaic conversion techniques. TiO2 nanotube arrays (TiO2 NAs) can be grown directly on the surface of metal Ti by the anodic oxidation method. Bi2S3 and PbS nanoparticles (NPs) were firstly co-sensitized on TiOa NAs (denoted as PbS/Bi2S3(n)/TiO2 NAs) by a two-step process containing hydrothermal and sonication-assisted SILAR method. When the concentration of Bi3+ is 5 mmol/L, the best photoelectrical performance was obtained under simulated solar irradiation. The short-circuit photocurrent (Jsc) and photoconversion efficiency (η) of PbS/Bi2S3(5)/TiO2 NAs electrode were 4.70 mA/cm and 1.13 %, respectively.展开更多
(Ba0.4Pb0.3)Sr0.3TiO3 thin films were fabricated via pulsed laser deposition (PLD) technique on Pt/TiO2/SiO2/Si substrate. The crystallization of the films was characterized by XRD and FSEM, and the experimental r...(Ba0.4Pb0.3)Sr0.3TiO3 thin films were fabricated via pulsed laser deposition (PLD) technique on Pt/TiO2/SiO2/Si substrate. The crystallization of the films was characterized by XRD and FSEM, and the experimental results suggested deposition parameters, especially the deposition temperature was the key factor in forming the perovskite structure. The dielectric properties of the film deposited with optimized parameters were studied by an Agilent 4294A impedance analyzer at 1 MHz. The dielectric constant was 772, and the loss tangent was 0.006. In addition, the well-shaped hysteresis loop also showed that the film had a well performance in ferroelectric. The saturated polarization P, remnant polarization Pr and coercive field E were about 4.6 μC/cm2, 2.5 μC/cm2 and 23 kV/cm (the coercive voltage is 0.7 V), respectively. It is suggested the film should be a promising candidate for microwave applications and nonvolatile ferroelectric random access memories (NvFeRAMs).展开更多
Nano particles lanthanum modified lead titanate (PLT) thin films are grown on Pt/Ti/SiO 2/Si substrate by liquid source misted chemical deposition (LSMCD). PLT films are deposited for 4-8 times, and then annealed at v...Nano particles lanthanum modified lead titanate (PLT) thin films are grown on Pt/Ti/SiO 2/Si substrate by liquid source misted chemical deposition (LSMCD). PLT films are deposited for 4-8 times, and then annealed at various temperature. XRD and SEM show that the prepared films have good crystallization behavior and perovskite structure. The crystallite is about 60 nm. The deposition speed is 3 nm/min. This deposition method can exactly control stoichiometry ratios, doping concentration ratio and thickness of PLT thin films. The best annealing process is to bake at 300 ℃ for 10 min and anneal at 600 ℃ for 1 h.展开更多
This work investigated the microwave dielectric properties of A-site substitution by rare earth La3+in(Pb0.5Ca0.5)(Fe0.5Ta0.5)O3(PCFT) system.A single perovskite phase was obtained only when the doping content ...This work investigated the microwave dielectric properties of A-site substitution by rare earth La3+in(Pb0.5Ca0.5)(Fe0.5Ta0.5)O3(PCFT) system.A single perovskite phase was obtained only when the doping content was 2%.Suitable La3+ doping improved microwave dielectric performances.Excessive La3+doping caused the formation of secondary phase,which resulted in the decreasing of permittivity εrand quality factor Qfvalues.Especially,when the doping content is 2%-5%,permittivity εrwas above 75 and Qfvalues were 6 902-7 416 GHz.展开更多
基金supported by Program of International S&T Cooperation(2013 DFA51050)National Magnetic Confinement Fusion Science Program(2013GB110001)+2 种基金the 863Program(2014AA032701)the National Natural Science Foundation of China(11405138,51302231)the Western Superconducting Technologies Co.,Ltd
文摘TiO2 films have been widely applied in photo- voltaic conversion techniques. TiO2 nanotube arrays (TiO2 NAs) can be grown directly on the surface of metal Ti by the anodic oxidation method. Bi2S3 and PbS nanoparticles (NPs) were firstly co-sensitized on TiOa NAs (denoted as PbS/Bi2S3(n)/TiO2 NAs) by a two-step process containing hydrothermal and sonication-assisted SILAR method. When the concentration of Bi3+ is 5 mmol/L, the best photoelectrical performance was obtained under simulated solar irradiation. The short-circuit photocurrent (Jsc) and photoconversion efficiency (η) of PbS/Bi2S3(5)/TiO2 NAs electrode were 4.70 mA/cm and 1.13 %, respectively.
基金the National Natural Science Foundation of China(No.60571009)
文摘(Ba0.4Pb0.3)Sr0.3TiO3 thin films were fabricated via pulsed laser deposition (PLD) technique on Pt/TiO2/SiO2/Si substrate. The crystallization of the films was characterized by XRD and FSEM, and the experimental results suggested deposition parameters, especially the deposition temperature was the key factor in forming the perovskite structure. The dielectric properties of the film deposited with optimized parameters were studied by an Agilent 4294A impedance analyzer at 1 MHz. The dielectric constant was 772, and the loss tangent was 0.006. In addition, the well-shaped hysteresis loop also showed that the film had a well performance in ferroelectric. The saturated polarization P, remnant polarization Pr and coercive field E were about 4.6 μC/cm2, 2.5 μC/cm2 and 23 kV/cm (the coercive voltage is 0.7 V), respectively. It is suggested the film should be a promising candidate for microwave applications and nonvolatile ferroelectric random access memories (NvFeRAMs).
文摘Nano particles lanthanum modified lead titanate (PLT) thin films are grown on Pt/Ti/SiO 2/Si substrate by liquid source misted chemical deposition (LSMCD). PLT films are deposited for 4-8 times, and then annealed at various temperature. XRD and SEM show that the prepared films have good crystallization behavior and perovskite structure. The crystallite is about 60 nm. The deposition speed is 3 nm/min. This deposition method can exactly control stoichiometry ratios, doping concentration ratio and thickness of PLT thin films. The best annealing process is to bake at 300 ℃ for 10 min and anneal at 600 ℃ for 1 h.
基金Project supported by the National Natural Science Foundation of China (Grant No.60578041)the National High Technology Research and Development Program of China (Grant No.715-006-0060)
文摘This work investigated the microwave dielectric properties of A-site substitution by rare earth La3+in(Pb0.5Ca0.5)(Fe0.5Ta0.5)O3(PCFT) system.A single perovskite phase was obtained only when the doping content was 2%.Suitable La3+ doping improved microwave dielectric performances.Excessive La3+doping caused the formation of secondary phase,which resulted in the decreasing of permittivity εrand quality factor Qfvalues.Especially,when the doping content is 2%-5%,permittivity εrwas above 75 and Qfvalues were 6 902-7 416 GHz.