Synthesis of highly aligned and ultralong coordination polymernanowires and their calcination to porous manganese oxide nanostructures

Abstract

We have demonstrated an extremely facile procedure for the preparation of 3D porous manganese oxide nanostructures by pyrolysis of Mn-based coordination polymer nanowires. The highly aligned and ultralong Mn-based polymer nanowires with high chemical purities were prepared using nitrilotriacetic acid (NA) as a chelating agent by a one-step hydrothermal approach. In the synthesis, NA was slowly dissolved in water and bonded with manganese ions by carboxyl groups to form one-dimensional polymer nanowires under the protection of isopropyl alcohol, and then form highly aligned nanowire bundles. Control experiments show that the morphologies of polymer nanowires greatly depend on the precursor salts and ratios between deionized water and isopropyl alcohol. Based on the elemental analysis results, the probable molecular formula and growth mechanism have been proposed. The catalytic reaction results demonstrated that the as-prepared 3D porous manganese oxide nanostructure was a good support for aerobic oxidation of benzyl alcohol. Moreover, the catalysts can be easily separated and recycled.