Free-standing copper(II) oxide nanotube arrays through an MOCVD template process

Metal-organic chemical vapor deposition (MOCVD) has been already used to fabricate CNTs, nickel nanowires, and TiO2 nanorods. Nevertheless, to our knowledge no attempts have been made for an MOCVD template synthesis of metal oxides nanotubes. In this perspective, the synthesis of copper oxide nanotubes through simple reproducible routes represents an appealing goal. CuO has been, in fact, extensively studied for several reasons from its close connection to high-Tc superconductors to its electrical and magnetic properties, from its use as a powerful heterogeneous catalyst to its potential as a cathode material in the fabrication of lithium copper oxide electrochemical cells. In particular, copper oxide based thin films have been used already in the field of heterogeneous catalysis and in gas-sensing devices. For these particular applications, the high surface-volume ratio and the nanometric size are expected to result in a tremendous improvement of chemical properties, thus rendering CuO nanotubes particularly appealing. In this paper, we report on the preparation of ordered homogeneous arrays of copper (II) oxide nanotubes through an MOCVD template route using Cu(tmhd)2 (Htmhd ) 2,2,6,6-tetramethyl-3,5-heptandione) as a source. The Cu(tmhd)2 has been chosen since it represents a suitable MOCVD precursor and has been widely applied for MOCVD fabrications of high Tc superconductors.