Hydrogenated SWNTs for Improved Processing of SWNTs

NSF Grant Number: EEC-0425826
PI(s): G. Miller, D. Tomanek
Student and Post-doctoral Researchers: J. Kintigh, S. Berber
Institutions: University of New Hampshire & MSU

Objective: The goals of the research were to exploit new polyamine chemistries developed at CHN for SWNT hydrogenation leading to highly dispersed, highly processable solutions of SWNTs.

Broader Impact: High-rate nanomanufacturing processes involving SWNTs generally require debundled, highly disperse tubes. We have developed a reliable, reversible, scalable chemistry to achieve this.

Significant Results: We combined experimental observations with ab initio calculations to gain a detailed, fundamental understanding of the reversible hydrogenation of SWNTs using high boiling polyamines as hydrogenation reagents. Experimental studies show that hydrogenated SWNTs disperse well in organic solvents and exist largely as debundled tubes. Our calculations provide an explanation for this behavior and identify preferential adsorption geometries at different percent H-coverages. We envision that our debundled, hydrogenated SWNTs can be combined with CHN nanotemplates to align and orient SWNTs across large wafers at high rate and with nanoscale precision.

Visual comparison of SWNT and H-SWNT suspensions in CH3OH for variable times after 30 s of low-power sonication. Time since sonication is 30s(a); 5 min(b); 1h(c); and 48h(d).	Transmission Electron Microscope (TEM) images of (a) bundled SWNTs before hydrogenation and (b) debundled H-SWNTs after polyamine hydrogenation.