Devices for analysis and characterization of materials using electrochemical-based multiple response techniques

New and innovative aspects

The techniques developed in our group have still been commercialized in compact instruments in collaboration with the company Metrohm Dropsens, however, the most advanced combinations are not yet commercially available. The modularity of the components allows them to be combined in the appropriate way to obtain the best results depending on each problem posed. Although the components used are well known, their assembly represents state-of-the-art technology in the international context.

Main advantages of its use

These techniques are relatively inexpensive compared to other types of instruments and are capable of providing a great deal of information.

Specifications

One of the techniques developed in our group, Bidimensional Spectroscopy, is outlined in the section "3. pictures". It shows a device for the simultaneous measurement of two optical signals and one electrical signal. In this particular case, the equipment consists of a light source whose radiation reaches the cuvette containing the studied material through optical fibers. Three electrodes connected to the potentiostat are inserted into the cell. The cuvette holder has anchor points for optical fibers, with lenses that collimate the incident light beam. This, after passing through the electrode and/or the solution in which the reaction is taking place, decreases or increases its intensity in proportion to the amount of absorbent material or reagents present in the cell. The emerging light is collected by optical fibers that lead it to the corresponding monochromator, where it is scattered at different wavelengths on a diode array detector. The temporal synchronization of the electrochemical and spectroscopic equipment is key, since small errors in the time record can lead to large errors in the calculated potentials. The control of the experiment and the registration of the data is carried out with two independent computers.

This scheme (see figure 1) of the experimental device is modified depending on the analytical techniques used, being able to work with different spectral ranges and even with laser sources that cause optical phenomena such as Raman scattering or molecular fluorescence. Our devices also allow the acquisition of Raman spectra simultaneously with measurements in the UV/Vis spectrum in both normal and parallel configuration. In addition, photoluminescence techniques combined with electrochemical and other spectroscopic techniques can be used.
Currently, suitable SERS substrates are also being developed for the detection/determination of molecules of interest in a particular way, obtaining high sensitivity and selectivity with good reproducibility.

Applications

Our technologies have been successfully applied to the study and characterization of new materials:
1. Conductive polymers
2. Metallic nanoparticles
3. Semiconductive nanoparticles
4. Carbon nanotubes
5. Graphene
6. Biomolecules
Undoubtedly, they can be used with more “classic” materials, as long as they are susceptible to being oxidized or reduced or undergo some type of transformation over time.

Current development status

Prototype phase

Desired business relationship

Commercial Agreement, License Agreement, Technical Cooperation: further development; Technical Cooperation: testing new applications; Technical Cooperation: adaptation to specific needs.