Light-emitting diode based shifted-excitation Raman difference spectroscopy (LED-SERDS)

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Optics

Background:

• Fluorescence interference is a significant challenge in Raman spectroscopy, often obscuring spectral signals.
• Existing methods to mitigate fluorescence can be complex or expensive.

Purpose of the Study:

• To present a cost-effective solution for reducing fluorescence interference in Raman spectroscopy.
• To demonstrate the utility of shifted-excitation Raman difference spectroscopy (SERDS) with a light-emitting diode (LED) for this purpose.

Main Methods:

• Utilized a light-emitting diode (LED) as the excitation source for Raman spectroscopy.
• Employed a conventional dielectric bandpass filter to narrow the LED's spectral bandwidth and stabilize its wavelength.
• Implemented angle-tuning of the bandpass filter to control and shift the excitation wavelength for SERDS.

Main Results:

• Successfully demonstrated a low-cost approach to overcome fluorescence interference.
• Acquired SERDS spectra by precisely controlling and shifting the LED excitation wavelength.
• The method shows potential for enhancing the quality of Raman spectral data.

Conclusions:

• The presented SERDS technique using an LED and angle-tuned filter provides an affordable and effective method to combat fluorescence interference.
• This approach simplifies the experimental setup while improving the reliability of Raman spectroscopy.
• The findings suggest broader applicability of this cost-effective technique in various analytical settings.