Magnetization for lower temperature, selective diamond and carbon nanotube formation: A milestone in carbon physicochemical condensation

Abstract

Diamonds and carbon nanotubes (CNTs) have extraordinary properties with the potential for vast technological and scientific advancements. However, the syntheses of these super materials have required extreme conditions. Recent synthetic developments surrounding catalytic chemical vapor deposition (CCVD) have contributed to more suitable, practical and economical preparations, but more progress is needed for better selectivity, purity, and mass production of CNTs and diamonds. Such synthetic advancements require a deeper understanding of the mechanisms of formation on the atomic scale. A recent comprehensive mechanism of Little suggests the importance of high-spin electronic states and the rehybridization mechanics of carbon atoms and metal atoms (for catalytic synthesis) during the nucleation and growth of CNTs and diamonds. The significance of these predictions is demonstrated in this work by using an intense, static magnetic field of several teslas to influence carbon fixation events during carbon CCVD. Single crystalline diamonds are discovered to nucleate and grow under the influence of the static magnetic field (19.3 T) under catalytic CVD conditions that normally result in carbon nanotubes. Furthermore, this technique results in a bottom-up approach for creating diamond nucleation sites on the basis of a so-called chemical preabrasion of the silicon substrate with the potential advantage of the control of seeding nucleation-site density and nonrandom patterning for larger single crystal diamond syntheses. This technique also provides a basis for diamond–CNT composite super materials. Moreover, the observed influence of high magnetic field on diamond formation provides implications concerning natural diamond genesis in the earth’s mantle and core in comparison to celestial diamond formation. Furthermore, these findings suggest uses of polarized and nonpolarized neutron irradiation for static and dynamic magnetic interactions, leading to diamond and CNT productivity, respectively.