The catalytic potential of high-k dielectrics for graphene formation

TL;DR

This paper explores how high-k dielectrics like MgO and ZrO2 can catalyze the growth of graphene nano-flakes at low temperatures, emphasizing the role of step edges in the process.

Contribution

It combines experimental microscopy and theoretical DFT studies to reveal the catalytic role of step edges on MgO in graphene formation.

Findings

Graphene nano-flakes grow at step edges on MgO (100).

DFT shows C2H2 decomposition and carbon adsorption at step edges.

Step sites are crucial for low-temperature graphene growth.

Abstract

The growth of single and multilayer graphene nano-flakes on MgO and ZrO2 at low temperatures is shown through transmission electron microscopy. The graphene nano-flakes are ubiquitously anchored at step edges on MgO (100) surfaces. Density functional theory investigations on MgO (100) indicate C2H2 decomposition and carbon adsorption at step-edges. Hence, both the experimental and theoretical data highlight the importance of step sites for graphene growth on MgO.