Steric Configuration-Controllable Carbon Nanotubes-Integrated SiC Membrane for Ultrafine Particles Filtration

Airborne fine particles have severe effects on abating the duration and efficiency of filters due to their high penetration probability. One-dimensional (1D) nanomaterials-constructed filters show great promise in efficient removal of fine particles. In this work, in situ growth of 1D nanostructure membrane without introducing a transition or sacrificial layer on large-pore SiC support was creatively developed. The controllable growth of carbon nanotubes (CNTs) via chemical vapor deposition (CVD) can bridge a loose structure on the neighbored SiC particles. This CNTs-constructed hierarchical structure can significantly ameliorate the large pores of the SiC support (SiC pore size ∼32.9 μm, CNTs/SiC membrane pore size ∼15 μm). By adjusting the CVD parameters, different configurations of CNT membranes were controllably prepared, in which the special structure of the CNT membrane (S-CNTs/SiC) showed a comparatively higher gas permeance of ∼450 m3/(m2·h·kPa) and fine particle removal efficiency (99.48%). In addition, the S-CNTs/SiC membrane also showed a good long-term filtration performance for fine particles. This work provides a new insight into the preparation of a 1D nanostructure membrane on large-pore ceramic supports high-efficient removal of fine particles.