CO₂ Storage in Novel CO₂-H₂O Phases at High Pressure

An effective method for capturing and storing carbon dioxide in order to reduce atmospheric concentration is currently a research area of high interest. We investigated the potential of CO₂ storage in H₂O compounds by using optical Raman spectroscopy to analyze the high-pressure behavior of a CO₂-H₂O system in-situ. Between 26.9 and 1.0 GPa, we observed a new CO₂-H₂O compound whose vibrational spectra differed dramatically from pure CO₂ and H₂O. When pressure was decreased to 1 GPa, the CO₂ vibrons and OH stretch reverted to those expected for pure CO2 and H2O respectively, indicating a CO₂-H₂O mixture rather than a CO₂-H₂O molecular compound. Based on the difference in spectra seen upon pressure cycling, as well as the difference in spectra seen at multiple locations inside the sample, we concluded that multiple forms of the CO₂-H₂O compounds may exist. Our results indicate that the initial structure and composition may play a role in compound formation. These novel materials have potential implications for increasing our understanding of CO₂ interactions with potential host materials for improved CO₂ storage applications.

This research was undertaken as part of Montgomery Blair High School's Senior Research Project (SRP) Program from spring 2008 to summer 2009.

This project was submitted to various high school research competitions, including Junior Science and Humanities Symposia Program, Siemens Competition, Montgomery County Science Fair, and Intel Science Talent Search.

The project was awarded:
2009 Intel Science Talent Search, Semifinalist
2009 Montgomery County Science Fair Senior Division in Chemistry, 3rd place ($50)
2009 American Society of Safety Engineers Senior Division, Winner ($500)