Electrophysical properties of hydroxylated endohedral metallofullerene with gadolinium

Dudnik, Alexander, I; Vnukova, Natalia G.; Drokin, Nikolay A.; Bondarev, Vitaliy S.; Shestakov, Nikolay P.; Tomashevich, Yevgeniy, V; Churilov, Grigory N. Source: JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, 135 10.1016/j.jpcs.2019.109094 DEC 2019

The paper presents the results of experimental measurements of constitutive and electrophysical properties in hydroxylated endohedral metallofullerene with gadolinium sample. We extracted endohedral metallofullerene from carbon condensate, synthesized in high-frequency arc discharge plasma. Later hydroxyl groups were added. Via methods of infrared and x-ray photoelectronic spectroscopy, it was established that the molecules of hydroxylated endohedral metallofullerene have the Gd@C82Ox(OH)y, x + y=(40–42) composition. The method of measuring the electrical impedance in the frequency range from 100 Hz to 100 MHz shows that the resulting hydroxylated fullerene is an ion conductor. The measured frequency dependences of the dielectric permittivity and conductivity of hydroxylated fullerene are explained based on the assumption of an inhomogeneous distribution of electric charges in the material volume. Dielectric-hysteresis loops in the frequency range of 25 Hz–1 MHz and temperature range of 80–300 K, and volt-ampere characteristics were measured. The obtained results imply the appearance of residual polarization induced by the electric field in hydroxylated fullerene. However, the constant dipole moment is absent.