Publications by authors named "Hiroshi Tabata"
We have separated carbon nanotubes through host-guest complexation using host molecules named "nanotweezers" and "nanocalipers". In this work, a host molecule named tetragonal "M-nanobrackets", consisting of a pair of dipyrrin nanocalipers corresponding to two brackets "[" and "]" tethered by two metals (M), is designed, synthesized, and employed to separate single-walled carbon nanotubes (SWNTs). A facile three-step process including one-pot Suzuki coupling is developed to synthesize M-nanobrackets in a 37% total yield (M = Cu).
View Article and Find Full Text PDFSome gas sensors exhibit significant increases in their sensitivity and response/recovery rates under light illumination. This photoactivation of the gas response is considered a promising alternative to conventional thermal activation, which requires high power consumption. Thin layers of molybdenum disulfide (MoS) are known to exhibit an effective photoactivated gas response under visible light.
View Article and Find Full Text PDFArticle Synopsis
- The study explores the gas-sensing capabilities of a van der Waals heterojunction made from graphene and a MoS flake, focusing on its sensitivity to nitrogen monoxide (NO) gas.
- Researchers ensured accurate measurements by passivating non-relevant areas, revealing that the device's resistance changed significantly (over 10 times) when exposed to 1 ppm NO under specific electrical conditions.
- The sensor's response varied depending on the applied reverse bias and back-gate voltages, showing improved sensitivity with increased reverse bias but reduced response at high forward bias or positive back-gate voltage.