A Mechanism for Highly Efficient Electrochemical Bubbling Delamination of CVD‐Grown Graphene from Metal Substrates

Abstract

In most cases, transfer of chemical‐vapor‐deposited 2D materials from metallic foil catalysts onto a target substrate is the most necessary step for their promising fundamental studies and applications. Recently, a highly efficient and nondestructive electrochemical delamination method has been proposed as an alternative to the conventional etching transfer method, which alleviates the problem of cost and environment pollution because it eliminates the need to etch away the metals. Here, the mechanism of the electrochemical bubbling delamination process is elucidated by studying the effect of the various electrolytes on the delamination rate. A capacitor‐based circuit model is proposed and confirmed by the electrochemical impedance spectroscopy results. A factor of 27 decrease in the time required for complete graphene delamination from the platinum cathodes is found when increasing the NaOH ratio in the electrolyte solution. The opposite trend is observed for delamination at the anode. The surface screening effect induced by nonreactive ions in the vicinity of the electrodes plays a key role in the delamination efficiency. The analysis is generic and can be used as a guideline to describe and design the electrochemical delamination of other 2D materials from their metal catalysts as well.

A Peeling Approach for Integrated Manufacturing of Large Monolayer h-BN Crystals

“…The most versatile route for this is 2DLM transfer from the CVD growth catalyst to the designated device, often including the vertical stacking of 2DLMs to form van der Waals heterostructures. A number of transfer methods have been proposed for CVD Gr and h-BN, including wet transfer, 12,13 dry transfer, [14][15][16] electrochemical delamination 17,18 and lift-off-transfer. 19 Progress in developing these methods has not kept pace with large-area 2DLM crystal growth and the introduction of contamination and damage remain major constraints, which is exceptionally severe in case of heterostructures that rely on atomically clean interfaces.…”

Vertically Aligned Graphene Coating is Bactericidal and Prevents the Formation of Bacterial Biofilms

“…Next, we tested SiO 2 and Au samples coated with PECVD graphene flakes aligned perpendicularly to the surface . Due to diffuse reflection, the graphene‐coated samples appear black ( Figure a) and the coating is very uniform (Figure b).…”

High responsivity sensing of unfocused laser and white light using graphene photodetectors grown by chemical vapor deposition

“…The graphene is grown by cold wall Aixtron high temperature CVD on Cu foils with a similar recipe to our previous work [9][10][11][12][13]. The device layout is shown in Fig.…”