Optimal boron-doped graphene substrate for glucose Raman signal enhancement

TL;DR

This study uses quantum simulations to show that high boron doping in graphene enhances its ability to amplify glucose's Raman signal, with molecule orientation being a key factor.

Contribution

It demonstrates that higher boron doping concentrations improve graphene's SERS performance for glucose detection through phonon analysis.

Findings

Higher doping concentrations increase Raman signal enhancement.

Molecule orientation significantly affects Raman response.

High concentration B-graphene is a promising SERS substrate for glucose.

Abstract

Surface Enhanced Raman Spectroscopy (SERS) is a highly sensitive and selective technique that greatly enhances the signal of an analyte, compared with its signal from classical Raman Spectroscopy, due to its interaction with a substrates surface. It has been shown that low concentration boron-doped graphene (B-graphene) enhances the Raman signal of simple organic molecules like pyridine. Recent studies also suggest that B-graphene can remain thermodynamically stable when doped with significantly higher concentrations of boron than previously observed. In this framework, we use quantum mechanical simulations to investigate the influence of dopant concentration and geometric distribution on the effectiveness of B-doped graphene as a SERS substrate, with glucose as analyte. By combining analysis of interatomic force constants and of phonon eigenvectors composition, we conclude that higher doping concentrations provide a larger enhancement to glucose's Raman signal, while the molecule orientation relative to the surface plays a fundamental role in the Raman response. We suggest that high concentration B-graphene presents itself as a potential substrate for SERS based detection of glucose, while the used phonon-based analysis can be promptly applied for the search of promising candidates as substrate materials for enhanced Raman response.