One nanometer thin carbon nanosheets with tunable conductivity and stiffness

TL;DR

This paper introduces a novel method to fabricate ultrathin (~1 nm) carbon nanosheets with tunable electrical conductivity and mechanical stiffness, suitable for applications like pressure sensors.

Contribution

It presents a new fabrication process for ultrathin carbon films with adjustable electrical and mechanical properties, advancing material design for nanoscale devices.

Findings

Electrical resistivity drops from ~10^8 to ~10^2 kOhm/sq upon pyrolysis.

Mechanical stiffness increases from ~10 to ~50 GPa after graphitization.

Nanosheets successfully integrated into a pressure sensor prototype.

Abstract

We present a new route for the fabrication of ultrathin (~1 nm) carbon films and membranes, whose electrical behavior can be tuned from insulating to conducting. Self-assembled monolayers of biphenyls are cross-linked by electrons, detached from the surfaces and subsequently pyrolized. Above 1000K, the cross-linked aromatic monolayer forms a mechanically stable graphitic phase. The transition is accompanied by a drop of the sheet resistivity from ~10^8 to ~10^2 kOhm/sq and a mechanical stiffening of the nanomembranes from ~10 to ~50 GPa. The technical applicability of the nanosheets is demonstrated by incorporating them into a microscopic pressure sensor