Temperature and spectroscopic characteristics of homogeneous co-deposited carbon–deuterium films produced in the T-10 tokamak

Abstract

Homogeneous carbon–deuterium (C‒ D) films with a high [D]/[C] ratio, redeposited on deuterium-plasma discharge in the T-10 tokamak, have been studied by means of thermogravimetric analysis, spectroscopy based on electron paramagnetic resonance, Fourier-transform infrared spectroscopy and photoluminescence spectroscopy. Deuterium was found to be accumulated only in the C‒ D2, 3 sp3 vibrational modes, including 633 and 1090 cm−1 deformation modes, and 2100–2200 cm−1 stretching modes, the intensity of which slightly diminished on annealing at 450 °C. Photoluminescence of an excitonic nature was found at 390–530 nm related to the C 2p π−π* transitions within the aromatic rings, and luminescence quenched at 450 °C. The luminescence excitation spectra at 3–10 eV showed similarity in peak positions to the luminescence excitation spectra of thin C60 films. Possible physical reasons explaining the effect of H‒ D‒ T isotopes on the accumulation and desorption of hydrogen are considered.