G.B.Liu
,
W.L.Wang
,
C.G.Hu
,
K.J.Liao
,
Q.Feng
,
L.H.Feng
金属学报(英文版)
The effect of annealing treatment on the structure of CdS films was investigated.The cadmium sulfide thin films were prepared by chemical bath deposition, and were annealed at nitrogen atmosphere at different temperatures. The films were charac-terized by SEM and XPS (X-ray photoelectron spectroscopy). X-ray photoelectron spectroscopy was used to examine the chemical states on the CdS films surface. It was found that thermal annealing could produce large grains of CdS thin films, remove the air contamination and reduce the oxygen content on the CdS films surface. Therefore,the CdS films changed more uniform and smoother surface after thermal annealing.
关键词:
XPS
,
null
,
null
C.G.Hu
,
W.L.Wang
,
K.J.Liao
,
W.Zhu
金属学报(英文版)
The electrochemical behavior of a carboxyl-modified carbon nanotube films was inves-tigated to explore its possibility in electroanalytical applicaton. Cyclic voltammetry of quinone was conducted in 1mol/L Na2SO4, which showed a stable, quasi-reversible voltammetric response for quinone / hydroquinone, and the anodic and the cathodic peak potentials were 0.657V and -0.029V (vs. SCE) at a scan rate of 0.1V.s^-1, re-spectively. Both anodic and cathodic peak currents depended linearly on the square root of the scan rate over the range of 0.01-0.5V.s^-1, which suggested that the process of the electrode reactions was diffusion-controlled. Carboxyl-modified carbon nanotube electrodes made it possible to determine low level of dopamine selectively in the pres-ence of a large excess of ascorbic acid in acidic media using derivative voltammetry.The results obtained were discussed in details. This work demonstrates the potential of carboxyl-modified carbon nanotube electrodes for electroanalytical applications.
关键词:
carbon nanotube
,
null
,
null
C.G.Hu
,
W.L.Wang
,
W.Zhu
金属学报(英文版)
Wide potential windows were found at carbon nanotube film electrodes in neutral solutions after being treated with nitric acid and mixed acid. Electrochemical re-versibility was investigated at carbon nanotube films with different pretreatments for ferri/ferrocyanide and quinone /hydroquinone. Carbon nanotube film electrodes pre-sented quasi-reversible electrochemical behavior for both electrolytes. In the range of scan rate, carbon nanotube film electrodes treated with acids showed heterogeneous electron-transfer properties, which was mainly controlled by its electron state density on the surface of the film. On the whole, the carbon nanotube electrode with nitric acid treatment presented the best electrochemical behaviors, so we chose it as an analytical electrode to determine the trace compound in dilute solution. The results demonstrated that this new electrode material exhibits superior performance characteristics for the detection of azide anion.
关键词:
carbon nanotubes
,
null
,
null
Y.B.Zhu
,
W.L.Wang
,
C.G.Hu
金属学报(英文版)
The influences of density and dimension of carbon nanotubes on their electron emis-sion from arrays are studied. The tip electric field of nanotubes, electric field enhance-ment factor, and optimum nanotube density are expressed by analytic equations. The theoretical analyses show that the field enhancement factor is sensitive to nanotube density, and can be sharply improved at a specific and optimum density. Some exper-iments have demonstrated these. Owning to electrostatic screening effect, the length of carbon nanotubes has little effect on their emission. A uniformly-distributed carbon nanotube array model is set up, and applied to analysis of carbon nanotube arrays.The results obtained here are in good agreement with the experimental data.
关键词:
carbon nanotube array
,
null
,
null
