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The synthesis of Cs-encapsulated single-walled carbon nanotubes (Cs@SWNTs) and double-walled carbon nanotubes (Cs@DWNTs) is realized by a plasma ion-irradiation method. Transmission electron microscopy observations confirm that chainlike and amorphous Cs fill SWNTs and DWNTs, respectively. The electronic transport properties of Cs@SWNTs and Cs@DWNTs are experimentally investigated at both room and low temperatures by fabricating them as the channels of field-effect transistor devices. Our results reveal that both Cs@SWNTs and Cs@DWNTs exhibit n-type semiconducting behavior at room temperature. The electronic properties of the Cs-encapsulated nanotubes can be controlled by adjusting the Cs filling levels during the plasma ion irritation process. At low temperatures, Coulomb blockade transport characteristics are observed for both encapsulated nanotubes, and the size of quantum dots formed in Cs@DWNTs is much smaller than that formed in Cs@SWNTs. More importantly, the n-type characteristics of Cs@SWNTs and Cs@DWNTs are found to remain stable, even in air, owing to Cs encapsulation. [ABSTRACT FROM AUTHOR]

The transport eddy-current loss of a nearly nonmagnetostrictive CoFeSiB amorphous wire under a large longitudinal bias field can be several times greater than the value commonly expected by the classical model. Related to the overlarge circular susceptibility under the same condition, this is attributed to the formation of disklike soft-magnetic microstructures around hard magnetic inclusions randomly embedded in a soft magnetic matrix. [ABSTRACT FROM AUTHOR]

Passivation of the electronic defect states at a SiNx/InGaAs interface has been achieved using (NH4)2Sx treatments of the InGaAs surface. The X-ray photoelectron spectroscopy technique was used to investigate the mechanism of sulfur passivation. The results indicate that sulfur treatment can effectively erase the native oxides, and S-In, S-Ga and S-As bondings are formed after sulfidation. The fabrication of Au/SiNx/InGaAs metal–insulator–semiconductor diodes has been achieved by depositing a layer of SiNx on (NH4)2Sx-treated n-InGaAs using the plasma enhanced chemical vapor deposition technique. The effect of passivation on the InGaAs surface before and after annealing was evaluated by current–voltage and capacitance–voltage measurements. The results indicate that the SiNx passivation layer exhibits good insulative properties. The annealing contributes to the decrease of the fixed charge density and the minimum surface state density, which are 4.5×1011 cm-2 and 3.92×1011 cm-2 eV-1, respectively. A 256×1 InP/InGaAs/InP heterojunction short-wavelength infrared detector, fabricated with the sulfidation plus a SiNx passivation layer, has shown a good response uniformity of 4.81%. [ABSTRACT FROM AUTHOR]

The transport properties of single-stranded DNA (ssDNA) wrapped single-walled carbon nanotubes (SWNTs) are studied from low to room temperature. Atomic force microscopy reveals a regularly patterned geometry of ssDNA molecules on the surface of SWNTs. Our measurements indicate that the semiconducting behavior of SWNTs is drastically changed after ssDNA modification, showing a clear charge-transfer process at room temperature. At low temperatures single-electron tunneling features are observed up to 80 K, demonstrating clearly that quantum dots in series are created in the SWNTs due to the ssDNA wrapping. [ABSTRACT FROM AUTHOR]

The authors report electrical transport properties of p-n junction based on semiconducting single-walled carbon nanotubes (SWCNTs). The formation of p-n junction is realized in SWCNTs, which are encapsulated with Fe nanoparticles at low filling fractions. The devices exhibit an excellent rectifying behavior, and no current down to 10-14 A level flows when the device is biased in reverse. During measurements performed in the temperature range from 10 to 300 K, the devices maintain high reproducibility. More importantly, even after exposure to air, the rectifying characteristic keeps stable, which strongly suggests that ideal p-n junction diodes can be fabricated by SWCNTs. [ABSTRACT FROM AUTHOR]

β-SiC nanoparticles (NPs) were anchored onto the surface of reduced graphene oxide (RGO) by a facile solvothermal method. The characterization results of the novel RGO-SiC composites indicate an effective chemical interaction between the RGO sheets and β-SiC NPs. Moreover, methylene blue (MB) dye was employed as a model pollutant to evaluate the adsorption and photocatalytic ability of the composites. It is found that the content of RGO sheets can significantly tune the adsorption and photocatalytic activity of various composites with an optimal value of 3 wt%. The enhancement of photocatalytic activity can be attributed to the synergistic effect of the accelerated separation of photogenerated electron-hole pairs, and the enhanced absorption ability for dyes is mainly due to the RGO sheets which work as an excellent photocatalyst supporter and offer electrons channel to accept and transfer the photogenerated carriers from excited β-SiC NPs. [ABSTRACT FROM AUTHOR]

Passivation of the electronic defect states at a SiNx/InGaAs interface has been achieved using (NH4)2Sx treatments of the InGaAs surface. The X-ray photoelectron spectroscopy technique was used to investigate the mechanism of sulfur passivation. The results indicate that sulfur treatment can effectively erase the native oxides, and S-In, S-Ga and S-As bondings are formed after sulfidation. The fabrication of Au/SiNx/InGaAs metal–insulator–semiconductor diodes has been achieved by depositing a layer of SiNx on (NH4)2Sx-treated n-InGaAs using the plasma enhanced chemical vapor deposition technique. The effect of passivation on the InGaAs surface before and after annealing was evaluated by current–voltage and capacitance–voltage measurements. The results indicate that the SiNx passivation layer exhibits good insulative properties. The annealing contributes to the decrease of the fixed charge density and the minimum surface state density, which are 4.5×1011 cm-2 and 3.92×1011 cm-2 eV-1, respectively. A 256×1 InP/InGaAs/InP heterojunction short-wavelength infrared detector, fabricated with the sulfidation plus a SiNx passivation layer, has shown a good response uniformity of 4.81%. [ABSTRACT FROM AUTHOR]