关键词:

硼酸锶, 超结构, 液相沉淀, 形成机理

Abstract:

SrB₆O_10^·5H₂O flower-like and jujube-like superstructures consisting of nanoplates were prepared by a facile solution route，in which NH₄HB₄O_7^·3H₂O and SrCl_2^·6H₂O were used as raw materials and the liquid precipitation method was adopted. The superstructures were characterized by SEM，TEM and XRD. The results of XRD and chemical analysis indicated that the products were single phase SrB₆O_10^·5H₂O and the purity was 99.5%. Experiments were carried out to investigate the growth mechanism of the flower-like structures with the assistance of the TEM and SEM analysis. The mechanism of spherical aggregation of the SrB₆O_10^·5H₂O nuclei followed by the strong anisotropic 2D crystal growth was proposed. The effects of reaction temperature and reactants concentrations were also studied. It was found that the sizes of the aggregates and nanoplates increased with the elevating of temperature. The structure of samples transformed from disordered aggregations into flower-like and jujube-like superstructures，and the temperature of 70℃ was a crucial point for the change of substructure nanoplates from irregular shape to rectangular shape，and from disordered aggregation to ordered aggregation. With a lower concentration of the strontium reactant，the degree of orderliness decreased and the aggregates consisting of disorderly arranged nanoplates were observed.

Key words:

硼酸锶, 超结构, 液相沉淀, 形成机理