In this work, diamond-like-carbon （DLC） films were deposited onto polycarbonate （PC） substrates by radio-frequency plasma-enhanced cheraical vapor deposition （RF PECVD）, and silicon films were prepared between D...In this work, diamond-like-carbon （DLC） films were deposited onto polycarbonate （PC） substrates by radio-frequency plasma-enhanced cheraical vapor deposition （RF PECVD）, and silicon films were prepared between DLC and PC substrates by magnetron sputtering deposition so as to improve the adhesion of the DLC films. The deposited films were investigated by means of field-emission scanning electron microscopy （FE-SEM）, X-ray photoelectron spectroscopy （XPS） and Raman spectroscopy. Subsequently, the following frictional and optical properties of the films were measured： the friction coefficient by using a ball-on-disk tribometer, the scratch hardness by using a nano-indenter, the optical transmittance by using a UV/visible spectrometer. The effects of incident power upon the frictional and optical properties of the films were investigated. Films deposited at low incident powers showed large optical gaps, which decreased with increasing incident power. The optical properties of DLC films correlated to the sp^2 content of the coatings. High anti-scratch properties were obtained at higher values of incident power. The anti-scratch properties of DLC films correlated to the sp^3 content of the coatings.展开更多
Nanocapacitors and nonvolatile ferroelectric random access memories require nanoscale thin film coatings with ferroelectric properties. One dimensional ferroelectric nanofibers are used in ferroelectric memory devices...Nanocapacitors and nonvolatile ferroelectric random access memories require nanoscale thin film coatings with ferroelectric properties. One dimensional ferroelectric nanofibers are used in ferroelectric memory devices owing to the fact that decrease of the dimensionality of the memory device elements will reduce the addressing and appreciably increase the storage capacity, Novel ZnO/BaO nanocomposite fibers exhibiting ferroelectric properties have been prepared in the form of non-woven mesh by electrospinning the sol derived from the sol-gel route, Thin cylindrical nanofibers of average diameter 100 nm have been obtained and their morphology is confirmed by SEM and AFM images. In the electrospinning process, the effect of the working distance on the fiber morphology was studied and it showed that working distance between 11 and 15 cm can produce fibers without beads and the decrease in working distance in this range increases the fiber diameter. Powder XRD was used to identify the phases and EDX analysis confirmed the presence of ZnO/BaO. Dielectric and non-linear optical properties have also been studied. The dielectric studies showed that ZnO/BaO composite nanofibers undergo a phase transition from ferroelectric to paraelectric at 323 K.展开更多
Vanadium oxides condensed films are prepared on glass substrates, using spray pyrolysis （SP） technique. The effects of substrate temperature, vanadium concentra- tion in initial solution and the solution spray rate ...Vanadium oxides condensed films are prepared on glass substrates, using spray pyrolysis （SP） technique. The effects of substrate temperature, vanadium concentra- tion in initial solution and the solution spray rate on the nano-structural, electrical, and optical properties of depos- ited films were investigated. Characterizations of the sam- ples were performed using X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and UV-Vis spec- troscopy methods. The type and concentration of the charge carriers were determined and measured by Hall effect experiment. XRD patterns showed that the prepared films had polycrystalline structure, mostly tetragonal fl-V205 and V409 phases with the preferred orientation along （200） direction. The Hall effect experiment revealed that all samples were n-type, except the ones deposited at substrate temperatures Tsub ： 300 ~C and Tsub = 450 ~C, vanadium concentration 0.1 mol/L and solution spray rate 10 mL/min. The charge carrier concentrations obtained were in the range 1016-1018 cm-3. The lowest sheet resistance （R~） was obtained for the samples prepared at T^ub = 450 ~C, vana- dium concentration 0.05 mol/L and solution spray rate 10 mL/min. It was also found that the optical transparency of the samples changed from 20% to 75% and the optical bandgap of the samples was from 2.22 eV to 2.58 eV, depending on the deposition conditions.展开更多
基金supported by China Postdoctoral Science Foundation Funded Project (Nos. 20100481209 and 201104569)a Grant (20120101220) from Liaoning Province of China+1 种基金a Grant (F11-264-1-74) from Shenyang City of Chinasupported by the Fundamental Research Funds for the Central Universities, China (No. N110403002)
文摘In this work, diamond-like-carbon （DLC） films were deposited onto polycarbonate （PC） substrates by radio-frequency plasma-enhanced cheraical vapor deposition （RF PECVD）, and silicon films were prepared between DLC and PC substrates by magnetron sputtering deposition so as to improve the adhesion of the DLC films. The deposited films were investigated by means of field-emission scanning electron microscopy （FE-SEM）, X-ray photoelectron spectroscopy （XPS） and Raman spectroscopy. Subsequently, the following frictional and optical properties of the films were measured： the friction coefficient by using a ball-on-disk tribometer, the scratch hardness by using a nano-indenter, the optical transmittance by using a UV/visible spectrometer. The effects of incident power upon the frictional and optical properties of the films were investigated. Films deposited at low incident powers showed large optical gaps, which decreased with increasing incident power. The optical properties of DLC films correlated to the sp^2 content of the coatings. High anti-scratch properties were obtained at higher values of incident power. The anti-scratch properties of DLC films correlated to the sp^3 content of the coatings.
文摘Nanocapacitors and nonvolatile ferroelectric random access memories require nanoscale thin film coatings with ferroelectric properties. One dimensional ferroelectric nanofibers are used in ferroelectric memory devices owing to the fact that decrease of the dimensionality of the memory device elements will reduce the addressing and appreciably increase the storage capacity, Novel ZnO/BaO nanocomposite fibers exhibiting ferroelectric properties have been prepared in the form of non-woven mesh by electrospinning the sol derived from the sol-gel route, Thin cylindrical nanofibers of average diameter 100 nm have been obtained and their morphology is confirmed by SEM and AFM images. In the electrospinning process, the effect of the working distance on the fiber morphology was studied and it showed that working distance between 11 and 15 cm can produce fibers without beads and the decrease in working distance in this range increases the fiber diameter. Powder XRD was used to identify the phases and EDX analysis confirmed the presence of ZnO/BaO. Dielectric and non-linear optical properties have also been studied. The dielectric studies showed that ZnO/BaO composite nanofibers undergo a phase transition from ferroelectric to paraelectric at 323 K.
文摘Vanadium oxides condensed films are prepared on glass substrates, using spray pyrolysis （SP） technique. The effects of substrate temperature, vanadium concentra- tion in initial solution and the solution spray rate on the nano-structural, electrical, and optical properties of depos- ited films were investigated. Characterizations of the sam- ples were performed using X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and UV-Vis spec- troscopy methods. The type and concentration of the charge carriers were determined and measured by Hall effect experiment. XRD patterns showed that the prepared films had polycrystalline structure, mostly tetragonal fl-V205 and V409 phases with the preferred orientation along （200） direction. The Hall effect experiment revealed that all samples were n-type, except the ones deposited at substrate temperatures Tsub ： 300 ~C and Tsub = 450 ~C, vanadium concentration 0.1 mol/L and solution spray rate 10 mL/min. The charge carrier concentrations obtained were in the range 1016-1018 cm-3. The lowest sheet resistance （R~） was obtained for the samples prepared at T^ub = 450 ~C, vana- dium concentration 0.05 mol/L and solution spray rate 10 mL/min. It was also found that the optical transparency of the samples changed from 20% to 75% and the optical bandgap of the samples was from 2.22 eV to 2.58 eV, depending on the deposition conditions.
