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In this work, we performed transient reflection measurements using the pump–probe protocol to investigate the influence of lattice defects induced by 380 keV argon (Ar) ions on the phonon dynamics of interlayer shearing (E 2 g 1 ) and in-plane carbon stretching (E 2 g 2 ) modes in highly oriented pyrolytic graphite (HOPG). The frequency and decay rate of E 2 g 1 - and E 2 g 2 -mode phonons were changed significantly at the fluence of 1 × 10 14 ions/cm 2. This indicated that significant structural changes in HOPG due to 380 keV Ar-ion irradiation were expressed as changes in the frequency and decay rate of phonons. In HOPG irradiated with 380 keV Ar + at the fluence of 1 × 10 14 ions/cm 2 , our measurement results indicated that compressive and tensile stresses contributed to in-plane and interlayer graphite structures, respectively. [ABSTRACT FROM AUTHOR]

Glassy carbon substrates were implanted with 100 keV platinum ions. The implanted samples were analyzed using cross-sectional transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy. Ion beam sputtering significantly affected the depth profile during platinum-ion implantation. Cross-sectional TEM revealed that the implanted platinum atoms were in the amorphous state and did not aggregate. Chemical state analysis of the platinum-ion-implanted glassy carbon substrates suggested that lattice defects in the substrates owing to the platinum-ion implantation caused the platinum–carbon interaction with electron transfer from platinum to carbon. [ABSTRACT FROM AUTHOR]