Comparative Raman Investigation of Hydrogen and Water Intercalation in Graphite under High Pressure
ORAL
Abstract
The high-pressure intercalation behavior of graphite with hydrogen and water was investigated using in situ Raman spectroscopy up to 10 GPa. Raman spectra were collected under compression to monitor structural and electronic modifications. Evidence of hydrogen intercalation into graphite was observed near 5.5 GPa, indicated by the appearance of distinct blue-shifted and split hydrogen vibron peaks. This pressure corresponds to the solidification of hydrogen, which significantly reduces its kinetic diameter and facilitates diffusion into the interlayer pores of graphite. In contrast, the graphite–water system exhibited no such anomalies. Comparative analysis of the G and 2D Raman bands between the two systems highlights the potential influence of molecular size, polarity, and chemical inertness on intercalation accessibility under high-pressure conditions.
*This work was supported by the NSF-DMR under Grant No. 1203834, the DTRA under Grant No. HDTRA1-12-01-0020, the ACS-PRF under Grant No. 54806-ND10, and the Alfred P. Sloan Foundation through the DCO-EPC. J. Lim acknowledges additional support from the Council on Faculty Research (CFR) at Eastern Illinois University through both the Fall 2024 and Summer 2025 awards. The research was performed at GeoSoilEnviroCARS (University of Chicago, Sector 13) from the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science user facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. GeoSoilEnviroCARS is supported by the National Science Foundation–Earth Sciences via SEES: Synchrotron Earth and Environmental Science (EAR2223273).
