Selective metal deposition at graphene line defects by atomic layer deposition

TL;DR

This paper demonstrates the selective deposition of platinum at graphene's line defects using atomic layer deposition, enhancing sensor performance by targeting defect sites for functionalization.

Contribution

It introduces a method for selective metal deposition at graphene defects via atomic layer deposition, improving sensor capabilities.

Findings

Pt selectively deposits on graphene's line defects

Enhanced hydrogen sensing performance at room temperature

Superior to non-selective Pt deposition methods

Abstract

One-dimensional defects in graphene have strong influence on its physical properties, such as electrical charge transport and mechanical strength. With enhanced chemical reactivity, such defects may also allow us to selectively functionalize the material and systematically tune the properties of graphene. Here we demonstrate the selective deposition of metal at chemical vapour deposited graphene's line defects, notably grain boundaries, by atomic layer deposition. Atomic layer deposition allows us to deposit Pt predominantly on graphene's grain boundaries, folds, and cracks due to the enhanced chemical reactivity of these line defects, which is directly confirmed by transmission electron microscopy imaging. The selective functionalization of graphene defect sites, together with the nanowire morphology of deposited Pt, yields a superior platform for sensing applications. Using Pt-graphene hybrid structures, we demonstrate high-performance hydrogen gas sensors at room temperatures and show its advantages over other evaporative Pt deposition methods, in which Pt decorates graphene surface non-selectively.