Growth of Inorganic Crystals on the Two-Dimensionally Oriented Molecular Surfaces

本研究旨在为建立一种基于无机-有机界面分子识别现象的无机功能材料的低温合成和形态控制方法奠定基础。在各种表面活性剂分子的Langmuir单分子膜下生长出羟基磷石、磁性和AgCl晶体，并在具有亲水性或疏水性表面的Langmuir- blodgett （LB）膜上气相沉积了Bi、Zn和Sn等金属。磷灰石和AgCl生长在单分子膜下，由于生长反应简单，其特定的晶体平面与单分子膜平行排列，而磁铁矿生长的薄膜由于反应过程复杂，没有表现出这种优先取向。研究发现，即使在只有弱界面相互作用才能利用的干燥过程中，分子识别也能有效地控制无机形态；大取向晶体生长在疏水表面。本研究结果表明，仿生材料的合成和形态控制具有广阔的应用前景。

The present study has been carried out for the purpose of establishing the fundamentals to develop a low-temperature synthesis and morphology control method for inorganic functional materials which is based on the molecular recognition phenomena at the inorganic-organic interfaces. Hydroxyapatete, magnetitie, and AgCl crystals were grown under Langmuir monolayrs of various surfactant molecules, and metals such as Bi, Zn, and Sn were vapor-deposited on the Langmuir-Blodgett (LB) films with either hydrophilic or hydrophobic surfaces. Apatite and AgCl were both grown under the monolayrs with their specific crystallographic planes aligning parallel to the monolayrs due to their simple growth reactions, while magnetite films grown exhibited no such preferred orientation possibly because of the complicated reaction process. Molecular recognition was found to be effective for controlling the inorganic morphology even in a dry process where only weak interface interactions can be utilized ; large oriented crystals were grown on the hydrophobic surface. The results obtained in the present study firmly indicate a promising future for biomimetic materials synthesis and morphology control.