Carbon nanotube array actuators

• Published in: Smart materials and structures Vol. 22; no. 9; pp. 94003 - 1-7
• Main Authors: Geier, S, Mahrholz, T, Wierach, P, Sinapius, M
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Bristol IOP Publishing 01.09.2013; Institute of Physics
• Subjects: Actuators; Alignment; Arrays; Carbon nanotubes; Chemical vapor deposition; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Materials science; Multi wall carbon nanotubes; Nanoscale materials and structures: fabrication and characterization; Nanotubes; Physics; Plasma enhanced chemical vapor deposition; Strain; Transducers; CV characteristic; Actuators; Multiwalled nanotube; Anisotropy; Carbon nanotubes; Electrolytes; Strain measurement; Vertical alignment; PECVD; Arrays; Ionic liquid
• ISSN: 0964-1726; 1361-665X
• DOI: 10.1088/0964-1726/22/9/094003

Experimental investigations of highly vertically aligned carbon nanotubes (CNTs), also known as CNT-arrays, are the main focus of this paper. The free strain as result of an active material behavior is analyzed via a novel experimental setup. Previous test experiences of papers made of randomly oriented CNTs, also called Bucky-papers, reveal comparably low free strain. The anisotropy of aligned CNTs promises better performance. Via synthesis techniques like chemical vapor deposition (CVD) or plasma enhanced CVD (PECVD), highly aligned arrays of multi-walled carbon nanotubes (MWCNTs) are synthesized. Two different types of CNT-arrays are analyzed, morphologically first, and optically tested for their active characteristics afterwards. One type of the analyzed arrays features tube lengths of 750-2000 μm with a large variety of diameters between 20 and 50 nm and a wave-like CNT-shape. The second type features a maximum, almost uniform, length of 12 μm and a constant diameter of 50 nm. Different CNT-lengths and array types are tested due to their active behavior. As result of the presented tests, it is reported that the quality of orientation is the most decisive property for excellent active behavior. Due to their alignment, CNT-arrays feature the opportunity to clarify the actuation mechanism of architectures made of CNTs.