Preparation of Carbon Nanotube Ink via Organic Hydrazine Treatment
Li-Hung Liu1, Jhih-Syuan Teng1,2,3*, Yao-Jane Hsu2, Pen-Cheng Wang1,3
1Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan
2National Synchrotron Radiation Research Center, Hsinchu, Taiwan
3Graduate Program for Science and Technology of Synchrotron Light Source, National Tsing Hua University, Hsinchu, Taiwan
* presenting author:鄧智烜,
In our experiment, we used four different hydrazines (hydrazine, phenylhydrazine, 2,4-dinitrophenylhydrazine and 2-nitrophenylhydrazine) to react with CNTs to prepare CNT-based inks. In our process, we used sodium dodecyl sulfate ( SDS ) to make inks, because (i) SDS nearly have no absorption over the visible spectrum region, and (ii) CNTs can be highly exfoliated by SDS. First, we prepared 10-mM SDS solution in deionized water, and then added enough CNTs to the above SDS solution. Subsequently, the solution was sonicated to make sure that CNTs could be well dispersed in the solution to benefit further reactions with organic hydrazines. After sonication, we added four different hydrazines to react with CNTs. The solutions were stirred for about 48 hours at ambient temperature for the reactions to proceed. After stirring, the solutions were diluted by DMF and then filtered through PTFE membrane filters to remove SDS and organic hydrazines. The obtained reaction adducts were suspended in DMF, sonicated and again filtered. After completing the ink preparation process, the ink samples were stored in vials and kept at ambient temperature to observe the stability of CNT dispersions as a function of time. We found that the ink with CNTs subjected to 2,4-dinitrophenylhydrazine treatment exhibited much better dispersion property than the inks with CNTs treated with other organic hydrazines. In other words, within 3 days, all ink dispersions began to bundle and precipitate after the sample vials were left on the bench top in our lab, except the sample with CNTs treated with 2,4-dinitrophenylhydrazine. Most importantly, the ink sample with CNTs treated with 2,4-dinitrophenylhydrazine were still well dispersed even after the sample vial was left on the bench top for 6 months.

Keywords: Carbon nanotube, Hydrazine, Graphene