U.S.-Australia Cooperative Research on the Synthesis of Ordered Composites on a Nanometer Sized Scale by Manipulation of Layered Compounds

该奖项支持德克萨斯农工大学的Abraham Clearfield博士访问澳大利亚墨尔本的CSIRO，与Terry Turney博士一起工作。研究人员建议结合两所机构在材料合成方面的专业知识，采用两种相关的合成方法合成新型无机纳米复合材料。在第一种方法中，粘土和其他层状化合物通过各种聚阳离子形成支柱，并经过热处理，将支柱分解成夹在主体层之间的氧化层。被柱状支撑的化合物包括粘土、四价磷酸盐、层状水合氧化物、层状钛酸盐、硅酸、K型层状尖晶石和层状双氢氧化物。后一类化合物由聚阴离子支撑。然后对这些柱状化合物进行热处理，将柱状化合物分解成夹在主体层之间的氧化层，从而形成陶瓷纳米复合材料。在第二个合成过程中，两个或多个层状化合物将被剥离成其单独的层，混合并重组成单相。将通过将悬垂的亲水有机基团连接到各层或在各层之间插入聚醚胺来制备去角质。各种各样的二价、三价和四价金属化合物都可以用这种方法处理。通过热去除有机物，酸处理去除插层胺，或磷酸盐的温和碱性水解来影响去角质的重建。最终退火的固体将是层间磷酸盐、氢氧化物或氧化物，并将构成具有新型催化、磁性和电学性质的新型固体。

This award supports a visit by Dr. Abraham Clearfield of Texas A&M University to CSIRO, Melbourne, Australia, to work with Dr. Terry Turney. The researchers propose to combine the expertise in materials synthesis of the two institutions to synthesize novel inorganic nanocomposite materials with two related synthetic procedures. In the first, clays and other layered compounds are pillared by a variety of polycations and thermally treated to decompose the pillar into a layer of oxide sandwiched between the host layers. Compounds to be pillared include clays, tetravalent phosphates, layered hydrous oxides, layered titanates, silicic acids, layered spinels of the type K and layered double hydroxides. The latter class of compounds is pillared by polyanions. These pillared compounds will then be treated thermally to decompose the pillar into sheets of oxide sandwiched between layers of the host, thus creating ceramic nanocomposites. In the second synthetic procedure, two or more layered compounds will be exfoliated into their individual layers, mixed and reconstituted into a single phase. The exfoliates will be prepared by either attaching pendent hydrophilic organic groups to the layers or intercalating a polyether amine between the layers. A wide variety of di-, tri- and tetravalent metal compounds may be manipulated in this fashion. Reconstitution of the exfoliates will be effected by thermal removal of the organic, by acid treatment to remove intercalated amines, or by gentle alkaline hydrolysis of the phosphonates. The final annealed solids will be interlayered phosphates, hydroxides or oxides, and will constitute new types of such solids with novel catalytic, magnetic and electrical properties.