Selective placement of carbon nanotubes on metal-oxide surfaces

We describe a method to selectively position carbon nanotubes on Al 2O 3 and HfO 2 surfaces. The method exploits the selective binding of alkylphosphonic acids to oxide surfaces with large isoelectric points (i.e. basic rather than acidic surfaces). We have patterned oxide surfaces with acids using both microcontact printing and conventional lithography. With proper choice of the functional end group (e.g., - CH 3 or - NH 2), nanotube adhesion to the surface can be either prevented or enhanced. © Copyright 2005 American Chemical Society.