Ultra-Fast, Chemical-Free, Mass Production of High Quality Exfoliated Graphene

Abstract

As graphene penetrates into industries, it is essential to mass produce high quality graphene sheets. New discoveries face formidable challenges in the marketplace due to the lack of proficient protocols to produce graphene on a commercial scale while maintaining its quality. Here, we present a conspicuous protocol for ultrafast exfoliation of graphite into high quality graphene on the sub-kilogram scale without the use of any intercalants, chemicals, or solvent. We show that graphite can be exfoliated using a plasma spray technique with high single-layer selectivity (∼85%) at a very high production rate (48 g/h). This is possible because of the inherent characteristics of the protocol which provides sudden thermal shock followed by two-stage shear. The exfoliated graphene shows almost no basal defect (I d/I g: 0) and possesses high quality (C/O ratio: 21.2, sp2 %: ∼95%), an indication of negligible structural deterioration. The results were reproducible indicating the adeptness of the protocol. We provided several proofs-of-concept of plasma spray exfoliated graphene to demonstrate its utility in applications such as mechanical reinforcements; frictionless, transparent conductive coatings; and energy storage devices.

Large‐Scale Syntheses of 2D Materials: Flash Joule Heating and Other Methods

“…used commercially available plasma spraying to exfoliate graphite using just argon and hydrogen gases ( Figure ). [ 98 ] Stringent characterization was carried out, showing 95% carbon content, 95% sp 2 character, and an average thickness of 1 nm with almost no discernable D peak character. Most impressively, production rates of up to 48 g h −1 are reported with no use of solvent.…”

Green Approach Toward In Situ Exfoliation and Enhanced Compatibility To Obtain Highly Conductive Polypropylene/Graphene Composites

“…The properties of the exfoliated FLG flakes in the composite powder were further analyzed using Raman spectroscopy due to its high sensitivity to basal-plane defects, edge defects, and layer counts of graphene . In a typical Raman spectrum of graphene-related materials, the shape and intensity of the 2D band are dominated by the layer number, the G key feature of the D band corresponds to the high-frequency E 2g phonon and the in-plane stretching of Sp 2 -hybridized CC bonds, and D band represents the defect density. , It can be seen from Figure a that the Raman spectrum of bulk graphite flakes exhibited a typical 2D band (≈1580 cm –1 ) and a G band (≈2700 cm –1 ). Apart from these bands, a weak D band also appeared at 1330 cm –1 , indicating a highly ordered structure with some defects .…”

“…The intensity of the D band of graphene in the PP/FLG composite was significantly increased, leading to an increase in the relative intensity ratio between D and G bands ( I D / I G ) from 0.07 to 0.69, suggesting that the ball milling induced high levels of grain size reduction and exfoliation, implying that some structural defects are further introduced into the FLG flakes. Notably, the increased defect density was due to the spatial scanning during testing and the formation of the higher number of graphene edges per unit weight of flakes. , In addition, a shoulder band has also appeared at 1612 cm –1 in the spectra of PP/FLG, which mainly originated due to the compounding of the exfoliated graphene with PP …”

Design and Deconstruction of Chemical Process Flow Based on Deep Learning

“…Chemical Process. Chemical processing is the method of converting raw materials into products through chemical processing [8]. e scope of this technology is actually very wide, and the operation process is also more.…”