Growth of aligned bamboo-structured carbon nanotubes via platinum catalyst
B. Brown, C.B. Parker, S.Y. Ma, B.R. Stoner, J.T. Glass
Duke University, US
Keywords: bamboo-structured carbon nanotubes, platinum catalyst, MPECVD growth
Abstract:Carbon nanotubes (CNTs) have a wide variety of unique properties and hence prospective applications that can directly benefit human health. These include biomaterials and biomedical devices for drug delivery and therapeutics, gene therapy, medical diagnostics, biosensing, tissue engineering, bone replacement, and neural prosthetics [1-3]. However, the feasibility of utilizing CNT-based biomaterials and devices in vivo critically depends on their biocompatibility. Notably, pristine CNTs possess some degree of toxicity primarily due to the presence of toxic metal catalyst impurities derived from the original catalyst material or support . Even post-processed or purified CNTs maintain a significant amount of non-encapsulated or bioavailable metal residue (1.2 – 14.3 %) . Although nanotube purification technologies continue to improve, they maintain a propensity to damage tube structure as well as add cost, time, and complexity from the additional processing [6-8]. One way to eliminate the need for purification and make CNT-based materials more viable for biomedical applications is to utilize a more biocompatible metal catalyst for CNT growth. Here, we report the first growth of vertically aligned, bamboo-structured, multi-walled, carbon nanotubes using physical vapor deposited Pt films on oxidized silicon substrates by microwave plasma enhanced chemical vapor deposition.