Synthesis of turbostratic nanoscale graphene via chamber detonation of oxygen/acetylene mixtures

Abstract

A study of the detonation synthesis method to make graphene and the properties of the resulting graphene is presented. The gaseous precursors are mixtures of oxygen and acetylene with oxygen/carbon molar ratios of O/C = 0.25 to 0.75. Chamber pressure and temperature data indicate pressures ≤ 300 psi and temperatures of 2550 ± 100K after initiation of the reaction mixture. The graphene material collected from the chamber after the detonation was characterized by Raman, XRD (X‐ray diffraction), BET, SEM (scanning electron microscopy), TEM (transmission electron microscopy), and so on. The material properties divide into two groups: low O/C (≤ 0.45) and high O/C (≥ 0.5). Low O/C graphene appears as a low density, aerosol gel with ∼8 weakly associated, disordered turbostratic layers with a lateral extent of 20 to 30 nm. High O/C graphene appears as a denser powder with ∼30 weakly associated turbostratic layers, with a lateral extent of 100 to 200 nm. We conclude, as we have previously, that the high detonation temperature during the reaction is the primary reason that graphene is formed rather than soot. Differentiation into two types of graphene products is hypothesized to be a result of aggregation kinetics to form a static gel that pre‐empts layering (stacking) when O/C is low.

Perforated Turbostratic Graphene As Active Layer in a Nonvolatile Resistive Switching Memory Device

“…However, another intense diffraction peak around 44° arises due to the relative rotation between the graphitic layers corresponding through the (101) plane. The appearance of these (101) planes indicates the turbostratic nature of the samples and is well agreed with the literature. − So, the peaks (100) and (101) are mostly due to the in-plane and out-of-plane distortion in the arrangement of the graphitic layers leading to the turbostratic behavior of the sample. The presence of the (101) plane and the (002) plane has also been observed in the SAED-TEM image, suggesting that our graphene sample is successfully converted to PTG.…”

Description of an activity-based enzyme biosensor for lung cancer detection

“…We have developed a biosensor using a graphene based backbone that relies on the reproducible structure of explosion-synthesized turbostratic graphene 22 . The Raman spectra of the core particle show characteristic graphene features with D , G , and 2D peaks centered at 1340, 1575, and 2680 cm −1 respectively (Supplementary Fig.…”

Thermoset/graphene polymer composites—A review of processing and properties

“…[ 26 ] Graphene is synthesized by the controlled detonation of acetylene and oxygen in a small chamber. [ 27 ] This is a unique, one‐step, highly efficient, gas‐phase, catalyst‐free process that is environmentally friendly, which yields graphene nanosheets. This eco‐friendly process to produce graphene was first discovered by Kansas State University and then patented in 2016.…”