Sensing Properties of Multiwalled Carbon Nanotubes Grown in MW Plasma Torch: Electronic and Electrochemical Behavior, Gas Sensing, Field Emission, IR Absorption

Abstract

Vertically aligned multi-walled carbon nanotubes (VA-MWCNTs) with an average diameter below 80 nm and a thickness of the uniform VA-MWCNT layer of about 16 μm were grown in microwave plasma torch and tested for selected functional properties. IR absorption important for a construction of bolometers was studied by Fourier transform infrared spectroscopy. Basic electrochemical characterization was performed by cyclic voltammetry. Comparing the obtained results with the standard or MWCNT‐modified screen-printed electrodes, the prepared VA-MWCNT electrodes indicated their high potential for the construction of electrochemical sensors. Resistive CNT gas sensor revealed a good sensitivity to ammonia taking into account room temperature operation. Field emission detected from CNTs was suitable for the pressure sensing application based on the measurement of emission current in the diode structure with bending diaphragm. The advantages of microwave plasma torch growth of CNTs, i.e., fast processing and versatility of the process, can be therefore fully exploited for the integration of surface-bound grown CNTs into various sensing structures.

Hollow carbon spheres and a hollow carbon sphere/polyvinylpyrrolidone composite as ammonia sensors

“…32 Thus, carbon based nanomaterials, being cheap and easily processable and with a high surface to volume ratio and tunable electrical properties, are advantageously applicable for use as resistive or capacitive chemical sensors. 17,33,34 Extensive research has been carried out on the synthesis and application of solid carbon spheres. However, the same cannot be said for their hollow carbon sphere (HCS) counterparts.…”

Preparation of ZnO/MWCNT/PP composite film and its application as multifunctional protective film

“…They proposed that the low‐density network formed by MWCNT imparts the surface, radiation trapping characteristic similar to an ideal black body . Majzlíková et al demonstrated that vertically aligned MWCNTs show strong absorption in 2.5–25 µm range . Preparation of SWCNT‐based IR absorber coating with absorbance of 90% has been previously demonstrated .…”

Plasma and Nanomaterials: Fabrication and Biomedical Applications

“…In particular, it can be applied for optical and biomedical devices, as well as various sensors. In a recent work, vertically aligned multi-walled carbon nanotubes were prepared with a diameter of less than 80 nm and uniform thickness of 16 μm, by employing microwave plasma torch with a high-speed process of only 60–120 s [99]. Carbon-encapsulated magnetic materials were also obtained by plasma as described in the previous section [88].…”