A platform for analysis of nanoscale liquids with an integrated sensor array based on 2-d material

TL;DR

This paper presents an integrated platform combining 2D material-based sensors, optical micro-spectroscopy, and atomic force microscopy for nanoscale liquid analysis, enabling real-time differentiation and molecular fingerprinting of liquids at the nanometer scale.

Contribution

The development of a novel, integrated nanoscale liquid analysis platform utilizing 2D materials and multimodal sensing techniques is a significant advancement over existing methods.

Findings

Successfully differentiated liquids electronically.

Recorded optical spectra of sub-attoliter droplets.

Demonstrated nanoscale sensitivity limits of the platform.

Abstract

Analysis of nanoscale liquids, including wetting and flow phenomena, is a scientific challenge with far reaching implications for industrial technologies. We report the conception, development, and application of an integrated platform for the experimental characterization of liquids at the nanometer scale. The platform combines the sensing functionalities of an integrated, two-dimensional electronic device array with in situ application of highly sensitive optical micro-spectroscopy and atomic force microscopy. We demonstrate the performance capabilities of the platform with an embodiment based on an array of integrated, optically transparent graphene sensors. The application of electronic and optical sensing in the platform allows for differentiating between liquids electronically, for determining a liquid's molecular fingerprint, and for monitoring surface wetting dynamics in real time. In order to explore the platform's sensitivity limits, we record topographies and optical spectra of individual, spatially isolated sessile oil emulsion droplets having volumes of less than ten attoliters. The results demonstrate that integrated measurement functionalities based on two-dimensional materials have the potential to push lab-on-chip based analysis from the microscale to the nanoscale.