SHARE
Research Highlight

Surfactant-Mediated Growth and Patterning of 2D Materials

Surfactant-Mediated Growth and Patterning of 2D Materials
(a) Mapping of Na acquired using time-of-flight secondary ion mass spectrometry (ToF-SIMS) showing Na accumulating on edges of MoS2 monolayer flakes.
(b) DFT calculations of the strain correlated with the number of Na atoms on edge, indicating Na atoms at the edge can notably relax the strain for small crystals.
(c) Illustration of lattice shrinkage induced by Na adsorption at the monolayer flake edges.

Scientific Achievement

A new surfactant-mediated growth mechanism was discovered that enables deterministic growth of large area 2D crystals.

Significance and Impact

The surfactant-mediated growth of 2D crystals enables the lithography-free, patterned growth of 2D materials for atomically thin electronic devices with desirable configurations.

Research Details

– Chemical vapor deposition growth of cm-scale and patterned 2D materials was achieved with pre-deposited NaBr additive. – STEM, ToF-SIMS, micro-XPS, and Raman spectroscopy combined with spin-polarized density functional theory (DFT) calculations clearly revealed the surfactant-mediated growth mechanism. – Field-effect transistor devices of cm-scale and patterned MoS2 monolayers show a high mobility of 50 cm2/Vs.   X. Li et al., "Surfactant-Mediated Growth and Patterning of Atomically Thin Transition Metal Dichalcogenides," ACS Nano (2020).  DOI: 10.1021/acsnano.0c00132