Boosting the sensitivity of solid-state gas sensors by incorporating nanostructured materials as the active sensing element can be complicated by interfacial effects. Interfaces at nanoparticles, grains, or contacts may result in non-linear current-voltage response, high electrical resistance, and ultimately, electric noise that limits the sensor read-out. Here we report the possibility to prepare nominally one atom thin, electrically continuous metals, by straightforward physical vapor deposition on the carbon zero-layer grown epitaxially on silicon carbide. With platinum as the metal, its electrical conductivity is strongly modulated when interacting with chemical analytes, due to charges being transferred to/from Pt. This, together with the scalability of the material, allows us to microfabricate chemiresistor devices for electrical read-out of chemical species with sub part-per-billion detection limits. The two-dimensional system formed by atomically-thin metals open up a route for resilient and high sensitivity chemical detection, and could be the path for designing new heterogeneous catalysts with superior activity and selectivity.
@article{arxiv.2003.01594,
title = {Chemical sensing with atomically-thin metals templated by a two-dimensional insulator},
author = {Kyung Ho Kim and Hans He and Marius Rodner and Rositsa Yakimova and Karin Larsson and Marten Piantek and David Serrate and Alexei Zakharov and Sergey Kubatkin and Jens Eriksson and Samuel Lara-Avila},
journal= {arXiv preprint arXiv:2003.01594},
year = {2020}
}