In this paper, we report a simple method to prepare bismuth nanoparticles from bulk bismuth. Bismuth nanoparticles of near spherical shape have been characterized by transmission electron microscopy ...(TEM), X-ray diffraction (XRD), and other techniques. Bismuth nanoparticles have mean diameter of 40–50 nm and exhibit the same crystal structure as the bulk bismuth. The surface of bismuth nanoparticle has been oxidized and the thermal analysis shows that bismuth samples contain at least 9 wt.% organic solvent and 76 wt.% metallic bismuth. The tribological property of bismuth nanoparticles as additives in oil is evaluated on a four-ball tester. The results show that bismuth nanoparticles exhibit good performance in wear.
The effect of calcination and reduction treatment on the photocatalytic activity of CO oxidation on Pt/TiO
2 was investigated at room temperature. The results showed that an optimum calcination ...temperature of CO photocatalytic activity was at 673
K for 2
h in air and the higher temperature detrimental to the enhancement of CO photocatalytic activity. The decreased photocatalytic activity of CO oxidation can be restored by the reduction in H
2 atmosphere at 773
K. The X-ray photoelectron spectroscopy (XPS) results show the Pt doped into TiO
2 particles when it was calcinated at 673
K for 2
h, which may bring about the enhancement of photocatalytic activity of CO oxidation.
The optimum calcination temperature of CO photocatalytic oxidation on Pt/TiO
2 was 673
K. XPS results show after calcinating at 673
K, Pt doped into TiO
2 lattice which can greatly enhance the CO photocatalytic activity.
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In this study, we report a novel and simple solution-phase route for one-dimensional metal nanocrystals. BiIn nanocrystals were prepared by directly dispersing melting BiIn alloy at an appropriate ...solvent. The as-obtained BiIn nanocrystals with a dendritic shape possess a good crystalline phase. The morphology of the nanocrystals can be greatly modified by changing the reaction parameters. This strong UV emission might arise from the quantum-confined In2O3 particles.
The anodic oxide film of aluminum formed in oxalic acid solution has a porous structure. The influence of pore-enlargement treatment on the porous structure and tribological properties of the film ...was investigated. After the pore-enlargement treatment, a method of synthesizing MoS
2 in the pores was used to improve the tribological properties of the film. The mechanism of friction reduction of MoS
2 synthesized in the pores of the film is also discussed. The results show that with the duration of pore-enlargement treatment, the diameter of the pores and the surface porosity of the film increase, and the hardness and wear resistance of the film decrease. The diameter of the pores and the surface porosity of the film increase to about 70 nm and 30%, respectively, the optimum values being obtained at 2 h, while the film still maintains its high hardness and good wear resistance. After self-lubricating treatment, the friction coefficient decreases from 0.87 to 0.65, and the wear rate of the steel ball decreases obviously. Since no MoS
2 transfer film is formed between the tribocouple faces, the lubricating effect of MoS
2 synthesized in pores of the film is limited.
In this paper, In2O3 nanocrystals were prepared by solution dispersion from bulk indium. In2O3 nanocrystals with an average diameter of 30 nm have a single-crystalline phase and appear as a square or ...rhombohedral shape, and little spherical particles are also present. In addition, these nanocrystals show strong ultraviolet-blue emission.
Fabrication and Tribological Properties of Pb Nanoparticles Zhao, Yanbao; Zhang, Zhijun; Dang, Hongxin
Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology,
02/2004, Letnik:
6, Številka:
1
Journal Article
In this paper, we describe a surfactant-assisted solution dispersion method to obtain metal nanoparticles, which involves dispersing and stabilizing metal droplets in an appropriate solvent. This ...method has been successfully used to prepare Pb nanoparticles from bulk Pb. The X-ray powder diffraction and transmission electron microscopy investigations show the formation of Pb nanoparticles possessing the same crystal structure as bulk metal and an average particle diameter of 40 nm. Thermal analysis indicates that Pb nanoparticles have organic shell, which is in agreement with the excellent oil-solubility. In addition, the tribological properties of Pb nanoparticles as additive in oil are discussed.PUBLICATION ABSTRACT
