Construction and differential growth mechanism of uniform and controllable CNTs and CNWs by ZIF-67 precursor

Abstract

Carbon nanotubes (CNTs) and carbon nanowires (CNWs) have been successfully derived from ZIF-67 nanoparticles which belongs to metal–organic frameworks on carbon cloth surface. Affected by the atmosphere, ZIF-67 nanoparticles derived ZIF-67@CNTs in a melamine environment while derived ZIF-67@CNWs in a C2H5OH environment. SEM, TEM, Raman, and so on were used to explore the construction of the ZIF-67@CNTs/CNWs modification layer on the carbon fiber surface. The macroscopic morphology of ZIF-67@CNTs/CNWs is influenced by ZIF-67 concentration. When the growth temperature rase, CNTs and CNWs’ graphite degrees significantly improved. CNTs and CNWs both adhere to the traditional tip-growth mode, whereas their growth mechanisms differ. “Bamboo-like” CNTs are formatted due to the different precipitation rates of graphite sheets (GSs), which are caused by catalyst particles in the solid and liquid phases. Solid CNWs are constructed with stacked GSs produced by single-phase catalyst particles. It is the phase uniformity of catalyst particles that ultimately determines the catalytic product.