Xiangyang XU
,
Yongwei ZHU
,
Baichun WANG
,
Zhiming YU
,
Shengzhong XIE
材料科学技术（英）
A technology of mechanochemical treatment (MCT) is introduced to modify nanodiamond (ND) surface aiming to obtaining a stable suspension with well-dispersed ND particles in aqueous medium. ND investigated in this paper is a purified product of nanometer-sized diamond synthesized by explosive detonation. As obvious aggregation and sediment were observed when the sample was added into deionized water, it is crucial to conduct deaggregation and dispersion investigations. Amid a series of mechanical treatments, i.e. grinding, stirring, ultrasonic and classification, some reagents are introduced to modify the newly created surface during aggregates comminution. For the co-effects of mechanical forces and surfactants, the mean size of particles was reduced and a stable system containing ND with narrow size distribution was prepared. Mechanism of surface reaction and modification are discussed, while AFM, Zetasizer3000HS, XRD, XPS and FTIR are utilized for the analysis. The functional chemical structure of ND particle surface and surface electrical property changed during the modification processes, and the dispersion character and stability of suspension can consequently be improved.
关键词:
Aggregates
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Yongwei ZHU
,
Feng XU
,
Jianliang SHEN
,
Baichun WANG
,
Xiangyang XU
,
Jianbin SHAO
材料科学技术（英）
Fourier transform infrared spectroscopy (FT-IR) and ζ-potential were introduced to study the effect of different modification parameters on the surface properties of nanodiamond (ND). Results showed that under stirring grinding conditions, ND hard aggregates were smashed and some active spots on them reacted with surfactant molecules, which led to the increase in its ³-potential and stability. Different models of surface modification were also given in this study.
关键词:
Surface modification
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Yongwei ZHU
,
Xiangqian SHEN
,
Zhijing FENG
,
Xiangyang XU
,
Baichun WANG
材料科学技术（英）
Several factors affecting the ζ-potential of nanodiamonds were studied. The Chemical Mechanical Modification (CMM) of surface, different surfactants and its dosage, and inorganic ions on the ζ-potential of nanodiamond sample L were studied using ZETASIZER3000HS and Nexus470. Results show that the ζ-potential changes with its parameters of detonation synthesis and purification. Results also suggest that CMM and subsequent treatments employed can alter apparently the ζ-potential and that some anionic surfactants increase the absolute value of the ζ-potential in the alkaline surrounding.
关键词:
Nanodiamond
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