硼酸镁一维纳米材料的制备和表征

Preparation and Characteristic of One-dimensional Magnesium Borate Nanomaterials

采用了溶剂热法(水和乙醇做溶剂)合成出了物相和形貌可控的一维硼酸镁纳米棒.研究结果表明,在溶剂的超临界状态下,无需表面活性剂的参与,能直接合成出一维硼酸镁纳米棒.通过对不同反应阶段生成产物的XRD结构分析,表明Mg2B2O5结构的形成经历了从Mg(OH)2到MgBO2(OH)的转变;通过对相应阶段生成产物的SEM观察,表明Mg2B2O5纳米棒的形貌经历了从片状到短柱状再到棒状的演变.分析认为Mg2B2O5纳米棒的形成遵循着形核→溶解→各向异性生长→再结晶的过程.

Single-crystalline magnesium borate nanorods were fabricated by solvothermal method at the super-critical conditions.This reaction condition enabled the formation of magnesium borate with one dimensional nanos-tructure without the involvement of surfactants.The microstructures of as-synthesized products prepared at different reaction stages were characterized by X-ray diffraction.The results show that Mg2B2O5 structure is obtained through an intermediate transition from Mg（OH）2 to MgBO2（OH）,and then from MgBO2（OH）to Mg2B2O5.The morphology of the products at corresponding stages were observed by scanning electron microscope（SEM）,showing that the formation process of Mg2B2O5 nanorods was from flake-like to short columnar and then to rod.The result suggests that the formation of Mg2B2O5 nanorods follow a process from nucleation → dissolution → anisotropic growing → recrystallization.