The electric and dielectric properties of metalloprotein, azurin, were studied at real molecular level by using conducting atomic force microscopy(C-AFM). Under a force lower than 2 nN, dielectric breakdown was observ...The electric and dielectric properties of metalloprotein, azurin, were studied at real molecular level by using conducting atomic force microscopy(C-AFM). Under a force lower than 2 nN, dielectric breakdown was observed. When reliable electrical contact between electrodes and protein is achieved under a force greater than 5 nN, well-behaved current-voltage characters are revealed, and dependent on the force load.展开更多
The study of size effect of conductivity of conducting polymer nanowires can be significant not only in the instruction of fabrication of the devices with nanodimension but also in basic research of inherence of nanom...The study of size effect of conductivity of conducting polymer nanowires can be significant not only in the instruction of fabrication of the devices with nanodimension but also in basic research of inherence of nanomaterials. PANI nanowires was fabricated in AAO templates by potentiostatic method. A new strategy of chemical modification of AAO template was introduced to prepare nanowires with smaller diameter. FTIR and contact angle measurements were used to characterize the modification. Tunneling Electron Microscopy results showed that the smaller PANI nanowires in diameter can be obtained in surfactant modified AAO templates. Conductivity of single PANI nanowire had been measured by Conductive Atomic Force Microscopy. The results displayed that the conductivity of PANI nanowire increase while the decrease of the diameter of PANI nanowires, which was called size effect of conductivity of PANI nanowires. The size effect had been attributed to order polymer chains orientation of PANI nanowire, which had been confirmed by electron diffraction diagrams.展开更多
PANI nanodots array was fabricated in AAO template with potentiostatic method in a short time.The topographic image of PANI nanodots array was characterized by scanning electron microscopy(SEM) and atomic force micros...PANI nanodots array was fabricated in AAO template with potentiostatic method in a short time.The topographic image of PANI nanodots array was characterized by scanning electron microscopy(SEM) and atomic force microscopy(AFM).The I-V characteristics of conducting PANI nanodots array was measured with conducting atomic force microscope(C-AFM) in atmosphere at room temperature.Coulomb staircase phenomena was observed in the I-V curves.展开更多
采用脉冲激光沉积法,在Pt/SiO2/Si的基底上制备CeO2薄膜,并使用导电原子力显微镜（Conductive Atomic Force Microscopy, CAFM）对CeO2薄膜的局域阻变效应及其形成机制进行了研究.结果表明,CeO2薄膜具有双极性阻变特性,且复位过程中出...采用脉冲激光沉积法,在Pt/SiO2/Si的基底上制备CeO2薄膜,并使用导电原子力显微镜（Conductive Atomic Force Microscopy, CAFM）对CeO2薄膜的局域阻变效应及其形成机制进行了研究.结果表明,CeO2薄膜具有双极性阻变特性,且复位过程中出现多阻态,限流值的大小影响开启的导电通道数量,并对其低组态阻值和开关比有显著影响.采用导电细丝模型对CeO2薄膜的阻变机制进行分析,表明氧缺位的形成及其在电压作用下的迁移是导电细丝形成和破灭的关键.展开更多
Thin films of perovskite manganese oxide La0.66Ca0.29K0.05MnO3(LCKMO) on Au/ITO(ITO=indium tin oxide) substrates were prepared by off-axis radio frequency magnetron sputtering and characterized by X-ray diffraction(XR...Thin films of perovskite manganese oxide La0.66Ca0.29K0.05MnO3(LCKMO) on Au/ITO(ITO=indium tin oxide) substrates were prepared by off-axis radio frequency magnetron sputtering and characterized by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM),and conductive atomic force microscopy(C-AFM) at room temperature.The thin films with thickness ranged from100nm to300 nm basically show cubic structures with a=0.3886 nm,the same as that of the raw material used,but the structures are highly modulated.C-AFM results revealed that the atomic scale p-n junction feature of the thin films was the same as that of the single crystals.The preparation of the thin films thus further confirms the possibility of their application extending from micrometer-sized single crystals to macroscopic thin film.展开更多
文摘The electric and dielectric properties of metalloprotein, azurin, were studied at real molecular level by using conducting atomic force microscopy(C-AFM). Under a force lower than 2 nN, dielectric breakdown was observed. When reliable electrical contact between electrodes and protein is achieved under a force greater than 5 nN, well-behaved current-voltage characters are revealed, and dependent on the force load.
文摘The study of size effect of conductivity of conducting polymer nanowires can be significant not only in the instruction of fabrication of the devices with nanodimension but also in basic research of inherence of nanomaterials. PANI nanowires was fabricated in AAO templates by potentiostatic method. A new strategy of chemical modification of AAO template was introduced to prepare nanowires with smaller diameter. FTIR and contact angle measurements were used to characterize the modification. Tunneling Electron Microscopy results showed that the smaller PANI nanowires in diameter can be obtained in surfactant modified AAO templates. Conductivity of single PANI nanowire had been measured by Conductive Atomic Force Microscopy. The results displayed that the conductivity of PANI nanowire increase while the decrease of the diameter of PANI nanowires, which was called size effect of conductivity of PANI nanowires. The size effect had been attributed to order polymer chains orientation of PANI nanowire, which had been confirmed by electron diffraction diagrams.
文摘PANI nanodots array was fabricated in AAO template with potentiostatic method in a short time.The topographic image of PANI nanodots array was characterized by scanning electron microscopy(SEM) and atomic force microscopy(AFM).The I-V characteristics of conducting PANI nanodots array was measured with conducting atomic force microscope(C-AFM) in atmosphere at room temperature.Coulomb staircase phenomena was observed in the I-V curves.
文摘采用脉冲激光沉积法,在Pt/SiO2/Si的基底上制备CeO2薄膜,并使用导电原子力显微镜（Conductive Atomic Force Microscopy, CAFM）对CeO2薄膜的局域阻变效应及其形成机制进行了研究.结果表明,CeO2薄膜具有双极性阻变特性,且复位过程中出现多阻态,限流值的大小影响开启的导电通道数量,并对其低组态阻值和开关比有显著影响.采用导电细丝模型对CeO2薄膜的阻变机制进行分析,表明氧缺位的形成及其在电压作用下的迁移是导电细丝形成和破灭的关键.
基金Supported by the National Natural Science Foundation of China(No.90922034)
文摘Thin films of perovskite manganese oxide La0.66Ca0.29K0.05MnO3(LCKMO) on Au/ITO(ITO=indium tin oxide) substrates were prepared by off-axis radio frequency magnetron sputtering and characterized by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM),and conductive atomic force microscopy(C-AFM) at room temperature.The thin films with thickness ranged from100nm to300 nm basically show cubic structures with a=0.3886 nm,the same as that of the raw material used,but the structures are highly modulated.C-AFM results revealed that the atomic scale p-n junction feature of the thin films was the same as that of the single crystals.The preparation of the thin films thus further confirms the possibility of their application extending from micrometer-sized single crystals to macroscopic thin film.
基金Supported by the National Basic Research Programme of China under Grant No 2007CB935402, and the National Natural Science Foundation of China under Grant Nos 50502036 and 60644002.
