Raman Spectrometer Development for River-side Water Quality Monitoring

Raman Spectrometer Development for River-side Water Quality Monitoring

In this blog post, we would like to focus on the key hardware developments i.e. Raman spectrometer for the water quality analysis. As we mentioned in our previous posts, Raman spectroscopy is a very sensitive technique that allows us to identify many contaminants in the water such as Ecoli, nitrate and other nutrients.

 The Nanophotonics group at CAPPA, Cork Institute of Technology (CIT), has been developing a compact Raman spectrometer that can be deployed for river-side water quality monitoring. This system requires a careful consideration of power consumption and heat dissipation, as the laser and the spectrometer-the main hardware components in a Raman system are power hungry. Moreover, air ventilation is problematic in the systems we are considering. Therefore, we had to search for a spectrometer that doesn’t require air ventilation and is still able to perform on par with TE cooled spectrometers. More importantly, it should consume as little power as possible.

 

Figure: Various spectrometers tested to build the “Buoy version” of the Raman system.

For this purpose, a variety of spectrometers from various manufactures such as Ocean Optics, Hamamatsu and Wasatch were tested (shown in the Figure above). After an extensive set of experiments, we found a suitable spectrometer for the purpose. Similarly, we identified a powerful laser that consumes low power and that can be powered from a DC source. Following these experiments, both the laser and spectrometer are acquired. Currently, CAPPA-CIT team is discussing with the Nimbus hardware team to build a suitable power source, so that entire system can be powered from a DC battery source. Furthermore, we are testing the power consumption, operational time of the device, placement of the hardware on the buoy and protection of the Raman probe. We will update this progress in the next blog post.