Microemulsion nanoreactor applied for the synthesis of iron-based catalysts for carbon nanotube formation

Catalysts play an important role in the production of carbon nanotubes, and the preparation of catalysts has always been a hot topic. In this study, microemulsion nanoreactor was constructed and applied for the first time to prepare carbon nanotube catalysts. The natural "pool" formed with the oil phase as an external substance and the surfactant as the boundary provides a reactor stable at the nanometer level for the co-precipitation reaction of Fe (NO3)3 center dot 9H2O and Al (NO3)3 center dot 9H2O, and the precipitation reaction is more uniform and sufficient. The active ingredient of the catalyst has better dispersion. Carbon nanotubes are nucleated with the active ingredient as the site and have a smaller and uniform diameter. Moreover, we want to control the size of the reactor by changing the surfactant concentration. The best performance was obtained when the surfactant content is 14 %, with the hydration diameter of microemulsion prepared of about 50 nm, the particle size and specific surface area of catalyst of about 60 nm and 255.97 m2/g. The diameter of carbon nanotubes grown under the catalyst was mainly distributed between 6 and 13 nm, with low defect degree. The results show that the reverse microemulsion method has unique advantages in the preparation of nano-scale materials, and this study provides a reference for the preparation of carbon nanotubes catalysts using microemulsion nanoreactor.