The first oxide nanotubes with alternating inter-layer distances

A novel type of vanadium oxide nanotube (VOx-NT) has been discovered in the course of a comprehensive study investigating the influence of ammonia on the tube formation. Compared to the conventional vanadium oxide nanotubes p repared at pH values between four and eight, the new tubes were obtained un der slightly basic conditions (pH 9-10). adjusted by ammonia. As revealed b y transmission electron microscopy images, the wall structure comprises two different inter-layer distances that occur alternately. Such a wall struct ure is without precedent in any other tubular material. (C) 2001 Elsevier S cience B.V. All rights reserved.