Multicolored carbon nanotubes: decorating patterned carbon nanotube microstructures with quantum dots.

In this work, techniques to create patterned array of multiwalled nanotube (MWNT) microstructures decorated with quantum dots (QDs) were presented. Using aligned array of intertwined MWNTs as the supporting template, a droplet of solution comprising QDs was deposited onto the MWNTs. When the solution evaporated away, QDs were left behind on the MWNT template. Coupled with the technique of laser pruning, a wide variety of QDs-decorated MWNT microstructures were created. In addition, the aligned array of MWNTs was found to be an effective nanosieve that could effectively sort out QDs with a size difference of approximately 0.5 nm. In this case, a droplet of solution comprising QDs of different sizes was placed on aligned array of MWNTs. As the solution spread across as well as trickled down the MWNTs, the smaller QDs were found to venture further and deeper into the MWNTs. Again coupled with laser pruning, fluorescence microscopy revealed multicolored MWNT microstructures due to preferential decoration of these QDs with difference sizes. As a result, multicolored/multicomponents hybrid functional materials were achieved.