Toward a quantitative theoretical method for infrared and Raman spectroscopic studies on single-crystal electrode/liquid interfaces

Abstract

An integrated approach for quantitatively predicting the electrochemical-infrared and electrochemical-Raman spectra and STM images of Pt(111)(2 × 2)-3CO adstructures has been developed.

Revisiting the Atomistic Structures at the Interface of Au(111) Electrode–Sulfuric Acid Solution

“…This computational method can quantitatively calculate the electrochemical Stark tuning slope (the slope of the vibrational frequency as a function of the applied potential) and importantly, the spectral intensities of adstructures at the single-crystal electrodes/liquid interfaces by simultaneously considering the surface charge, solvation effect, and high precision requirement for calculating the spectral intensities. 34 We found that the calculated EC-STM image and EC-IR and EC-Raman spectra of the Au(111) (√3 × √7)-(SO 4 •••w 2 ) configuration perfectly match with the respective experimental observations. Finally, we sketched a reaction free energy (ΔG re ) diagram 25 by calculating the potential-dependent Gibbs free energies G ads (V) of all configurations to further confirm the energetic preference for the adstructure, Au(111…”

“…The differential step size of Cartesian coordinates Δ x and electrostatic field strengths along the z axis Δ G z were set to 0.01 Å and 0.1 V/Å, respectively. The detailed computational methods of EC-IR and -Raman spectra were listed in ref . Other computational details are provided in the SI.…”

“…SHINERS has been proven to provide 4–6 orders of magnitude enhancement in Raman signals of adsorbates on metallic (e.g., Au, Cu, Pt) single-crystal electrodes − (see the working principles of SHINERS on transition-metal surfaces in Figure S1). To accurately interpret the features of the experimental spectra, we employed our newly developed computational method to calculate the EC-IR and EC-Raman spectra of nine possible configurations of Au(111)(√3 × √7)-X (X denotes the speculated adsorbates). This computational method can quantitatively calculate the electrochemical Stark tuning slope (the slope of the vibrational frequency as a function of the applied potential) and importantly, the spectral intensities of adstructures at the single-crystal electrodes/liquid interfaces by simultaneously considering the surface charge, solvation effect, and high precision requirement for calculating the spectral intensities .…”

“…To accurately interpret the features of the experimental spectra, we employed our newly developed computational method to calculate the EC-IR and EC-Raman spectra of nine possible configurations of Au(111)(√3 × √7)-X (X denotes the speculated adsorbates). This computational method can quantitatively calculate the electrochemical Stark tuning slope (the slope of the vibrational frequency as a function of the applied potential) and importantly, the spectral intensities of adstructures at the single-crystal electrodes/liquid interfaces by simultaneously considering the surface charge, solvation effect, and high precision requirement for calculating the spectral intensities . We found that the calculated EC-STM image and EC-IR and EC-Raman spectra of the Au(111)(√3 × √7)-(SO 4 ···w 2 ) configuration perfectly match with the respective experimental observations.…”

The rationality of using core–shell nanoparticles with embedded internal standards for SERS quantitative analysis based glycerol-assisted 3D hotspots platform

“…6,7 However, quantitative analysis for SERS is still full of challenges due to the arbitrary distribution of hotspots and poor reproducibility. 8,9 Developments in nanotechnology and analytical methods are urgently needed to break through this bottle-neck and move SERS towards broader practical application [10][11][12][13] and it is hoped that SERS quantitative detection 14 can be eventually realized.…”