In-situ Electrochemical Raman Spectroscopy Analytical Service

Overview

In-situ Electrochemical Raman Spectroscopy is a powerful characterization technique that combines electrochemistry and Raman spectroscopy, enabling real-time monitoring of structural and compositional changes of materials on the electrode surface during chemical reactions.

1. Electrochemistry: By applying a potential or current, redox reactions or other electrochemical processes are triggered on the electrode surface.

2. Conventional Raman Spectroscopy: When a laser illuminates a sample, most photons are scattered by the sample, while a small fraction of photons induce changes in molecular vibrational modes, generating Raman scattering. These scattered photons carry information about molecular vibrations, and their analysis through a spectrometer provides chemical and structural details of the sample.

3. Surface-Enhanced Raman Spectroscopy (SERS): Using metal nanostructures (e.g., gold, silver nanoparticles, or nanostructured metal surfaces) to enhance Raman signals. These metallic structures greatly amplify the Raman scattering intensity of molecules adsorbed on their surface. Compared to conventional Raman spectroscopy, the SERS effect can enhance Raman signals by up to 10⁶–10¹⁴ times, allowing detection of extremely low concentrations of molecules with higher sensitivity while providing detailed information about adsorbed species on the electrode surface.

Applications 

1. Electrocatalysis Research: Monitoring the structural and intermediate changes of catalysts during electrocatalytic reactions.
2. Battery Research: Investigating chemical changes during battery charge and discharge processes, such as the formation of the SEI (solid electrolyte interphase) layer in lithium-ion batteries.
3. Corrosion Science: Analyzing surface chemical changes during metal corrosion, studying the corrosion process and the formation of corrosion products.
4. Bioelectrochemistry: Monitoring the electrochemical behavior of biomolecules on electrode surfaces or detecting low concentrations of chemical substances or biomolecules.

Results Display

Reference: http://doi.org/10.1002/smll.202206531

To gain a deeper understanding of the effect of Er doping on the electrochemical oxygen evolution mechanism, in-situ electrochemical Raman spectroscopy was conducted. During the bias overpotential scan from 200 mV to 450 mV, two characteristic peaks observed at 457 and 538 cm⁻¹ were attributed to the Ni-O vibrations of the Ni(OH)₂ phase on the surface of NiFe-LDH@NF, indicating that OH⁻ preferentially adsorbs onto Ni sites (Figure c).

When the bias overpotential increased from 450 mV to 750 mV, the original surface Ni(OH)₂ phase transitioned to the NiOOH phase, with two new characteristic peaks appearing at 556 and 476 cm⁻¹, corresponding to Ni-OOH vibrations. The formed NiOOH phase is generally considered highly active for OER. However, the retention of the NiOOH phase in NiFe-LDH between 450 and 750 mV is attributed to the slow transformation cycle of Ni(OH)₂ to NiOOH at high overpotentials (Figure d).

In the Er-NiFe-LDH system, under the influence of Er doping, the adsorption of OH⁻ on Ni sites was significantly enhanced before 450 mV, as evidenced by the increase in Raman intensity, indicating improved OER activity at Ni sites (Figure e). As the bias overpotential increased from 450 to 750 mV, the vibrational mode of Ni-OOH gradually weakened, suggesting the evolution of Ni-OOH into O₂ (Figure f).

In summary, Er doping in NiFe-LDH disrupted the original Ni-OOH phase beyond 0.5 V and promoted the conversion of *OOH to O₂, thereby optimizing the slow kinetics of O₂ release and enabling Er-induced electronic modulation

Sample Requirement

• Electrocatalyst samples: Prepare at least 10 mg.
• Supercapacitor powder samples: Prepare at least 20 mg.
• Electrode sheet samples: Dimensions should be approximately 10 × 10 mm, with a thickness not exceeding 1 mm. The surface must be flat.
• Battery powder samples: Prepare at least 300 mg.

Note: The listed price is for reference only. Please request a quote for the final pricing.

Analytical Service Minimum order requirement: $250 per order. A $200 handling fee will be applied if order is below $250.

Please contact sales@msesupplies.com for additional information and instructions on our Analytical Services program. Confirmation of the sample(s) requirements, SDS sheets and additional information is needed prior to processing the Analytical Service order. 

***Please do not ship any samples without authorization from MSE Supplies***