What are SERS substrates?
Table of Contents
What are SERS substrates?
What is a SERS substrate? A Silmeco SERS substrate, called a SERStrate, is essentially a silicon wafer coated with a metal like gold or silver (or a custom metal of choice). The silicon wafer is made up of a special structure – ag/au coated nano-pillars – which facilitates molecular sensing (Raman scattering).
What is SERS analysis?
Surface enhanced Raman spectroscopy (SERS) is a powerful vibrational spectroscopy technique that allows for highly sensitive structural detection of low concentration analytes through the amplification of electromagnetic fields generated by the excitation of localized surface plasmons.
What is SERS effect?
The SERS effect involves the interaction of the metal surface plasmons with the electronic and vibrational states of the adsorbed molecules, under the influence of the oscillating electromagnetic radiation [18].
What is SERS enhancement factor?
The SERS enhancement factor (SERS-EF) is one of the most important parameters that characterizes the ability of a given substrate to enhance the Raman signal for SERS applications.
Why do we use SERS?
Surface-enhanced Raman spectroscopy (SERS) is a vibrational spectroscopy technique with sensitivity down to the single molecule level that provides fine molecular fingerprints, allowing for direct identification of target analytes.
How is SERS enhancement calculated?
The SERS enhancement factor (EF) is given by: EF= NvolIsurf/NsurfIvol where Nvol and Nsurf are the number of molecules probed in the aqueous sample and on the SERS substrates, respectively. Ivol and Isurf are the corresponding normal Raman and SERS intensities.
Why is gold used in SERS?
Among them, gold nanoparticles have stable properties, require a simple preparation process, and can be synthesized with a uniform particle size. Gold nanoparticles can not only be used as a research object in many experiments, but also as a SERS substrate.
What is significance of Hatta number in fluid fluid reaction?
The Hatta number (Ha) was developed by Shirôji Hatta, who taught at Tohoku University. It is a dimensionless parameter that compares the rate of reaction in a liquid film to the rate of diffusion through the film.
Why is effectiveness factor important?
The internal effectiveness factor is more useful. It characterizes the utilization of the internal surface of a catalyst particle and can provide guidance for catalyst manufacture and use.
What is unit of effectiveness factor?
We define the effectiveness factor as the average reaction rate with diffusion divided by the average reaction rate if the rate of reaction is evaluated at the bulk-stream (or boundary condition) values.
How do you calculate effectiveness factor?
For the heterogeneous systems with known constants to define the Thiele module φ, the effectiveness factor η can be obtained by calculating the Thiele module φ and then referring to the η–φ curve.
What is the significance of Hatta number?
