Spinel ZnMn2O4 nanoplate assemblies fabricated via "escape-by-crafty-scheme" strategy

A two-step process that differs in important details from previous methods used to prepare ZnMn2O4 nanoplate assemblies has been reported. This material was prepared by thermal transformation of metal-organic nanoparticles into metal-oxide nanoparticles based on the "escape-by-crafty-scheme" strategy. Firstly, the nanoscale mixed-metal-organic frameworks (MMOFs) precursor, ZnMn2-ptcda (ptcda = perylene-3,4,9,10-tetracarboxylic dianhydride), containing Zn2+ and Mn2+, was prepared by the designed soft chemical assembly of mixed metal ions and organic ligands at a molecular scale. In a second step, the MMOFs are thermally transformed into spinel structured ZnMn2O4 with morphology inherited from the MMOFs precursors. The well-crystallized spinel structure can be formed by thermal treatment of ZnMn2-ptcda at 350 degrees C, and is formed at temperatures >= 450 degrees C using the co-precipitation method. This "escape-by-crafty-scheme" strategy can be extended to the preparation of other spinel metal-oxide nanoparticles, e.g. CoMn2O4, and NiMn2O4, with well-defined morphology inherited from the metal-organic precursors. The ZnMn2O4 nanoplate assemblies thermally treated at 450 degrees C have potential application in lithium ion batteries as anode materials, which show high specific capacity and good cyclability