Infrared Nanospectroscopy at the Graphene–Electrolyte Interface

Publication Type

Journal Article

Date Published

07/2019

Abstract

We present a new methodology that enables studies of the molecular structure of graphene–liquid interfaces with nanoscale spatial resolution. It is based on Fourier transform infrared nanospectroscopy (nano-FTIR), where the infrared (IR) field is plasmonically enhanced near the tip apex of an atomic force microscope (AFM). The graphene seals a liquid electrolyte reservoir while acting also as a working electrode. The photon transparency of graphene enables IR spectroscopy studies of its interface with liquids, including water, propylene carbonate, and aqueous ammonium sulfate electrolyte solutions. We illustrate the method by comparing IR spectra obtained by nano-FTIR and attenuated total reflection (which has a detection depth of a few microns) demonstrating that the nano-FTIR method makes it possible to determine changes in speciation and ion concentration in the electric double and diffuse layers as a function of bias.

Journal

Nano Letters

Volume

19

Year of Publication

2019

Short Title

Nano Lett.

Refereed Designation

Refereed

Pagination

5388 - 5393

Issue

8

ISSN

1530-6984
Organization 
Research Areas