中文摘要：

采用激光液相法,以爆轰纳米金刚石（ PCD ）为原料,在聚乙二醇（ PEG200）溶液中得到单分散的纳米金刚石（ LPCD）。利用TEM、XRD、FTIR、VSM和PL光谱等手段对LPCD的形貌、粒径、发光和磁性能进行表征。结果表明,混酸氧化处理的PCD能稳定分散在PEG200溶液中,但仍有一次团聚体。采用激光辐照得到的LPCD,具有较强的铁磁性,更大的比表面积和更多的表面悬键。激光辐照的同时发生了原位表面化学修饰,LPCD出现了特有的羟基（ C-OH）峰和PEG200基团,粒子分散性好,没有一次和二次的团聚体,其平均粒径为5.5 nm。

英文摘要：

Nanodiamond powder obtained by explosive detonation with an average particle size of 360nm was oxidized by an acid mixture containing concentrated H2 SO4（98%） and H3 NO3（70%） with a volume ratio of 3：1, then dispersed with sonication in a polyethylene glycol solution（PEG200）, and finally irradiated with a 1064 nm laser for 1h to prepare a stable nanodiamond colloidal solution. TEM, XRD, FTIR, VSM and PL spectroscopy were used to characterize the properties of the nanodiamond particles, such as morphology, particle size, microstructure, luminescence and magnetic properties. Results show that the acid oxidation introduces surface functional groups on the nanodiamond powder, but there are still amorphous carbon and secondary aggregates in the stable nanodiamond suspension in PEG200 before the laser irradiation. Amorphous carbon is removed and the aggregates in the nanodia-mond suspension are broken into primary nanoparticles of 5 nm with the laser irradiation. The well-dispersed nanodiamond colloid in PEG200 solution after laser irradiation shows strong ferromagnetism and a high concentration of CC and C—OH bonds that favors the formation of the stable colloidal solution.