One-dimensional defects in graphene have a 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 temperature and show its advantages over other evaporative Pt deposition methods, in which Pt decorates the graphene surface non-selectively.
Bibliographical noteFunding Information:
We thank Tae Hoon Lee and John To for valuable discussion and technical assistance. We also thank Professor Oleg Yazyev for sharing a periodic graphene grain boundary model. This work was supported by Stanford Global Climate and Energy Program. Pt ALD was supported by the US Department of Energy, Office of Science, Basic Energy Sciences, under Award #DE-SC0004782. J.T.T. gratefully acknowledges the Academy of Finland (Grant 256800/2012) and the Finnish Cultural Foundation for financial support.
All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)
- Physics and Astronomy(all)