EPR AND MIXED IONIC-ELECTRONIC CONDUCTIVITY STUDIES OF PURE AND COPPER DOPED LAYERED LITHIUM SODIUM TITANATE (LiNa)Ti₃O₇

Abstract

Sodium (50%) mixed layered Li 2 Ti 3 O 7 and its 0.01, 0.05 & 1.0 molar percentage CuO doped derivatives have been prepared through high temperature solid state reaction and characterized through X-ray diffractometer, d.c. conductivity in the temperature range 373-700K and room temperature EPR investigation. Room temperature X-ray diffratograms confirm the phase evolution. Room temperature electron paramagnetic resonance (EPR) data show that Cu 2+ occupies Ti 4+ lattice sites giving rise to electric dipoles which increases electric permittivity. The absorption peak in EPR spectra gets broadened due to increased exchange interaction in heavily doped derivatives. Four distinct regions have been identified in the Ln(σT) versus 1000/T plots. Various electrical conduction mechanisms have involved during the whole temperature range of study

Electronic Structures and Electrical Properties of Cr2+-, Cu2+-, Ni2+-, and Zn2+-Doped Sodium Titanate Nanotubes

“…Figure 7 represents lnσ as a function of 1000/ T for the MNa-TNTs. The data revealed two different straight lines with different slopes pointing to the existence of two conduction mechanisms 13 , 40 at the low- and high-temperature regions. At a low temperature, the conduction appears to be characteristic of the host and is associated with the hopping process, including the free electrons from Ti 3 O 7 2– groups that jump from one Ti–Ti chain to another adjacent one.…”

“…In this method, Na + cations in sodium titanate nanotubes are replaced by different metal cations to form the desired metal-doped titanates, which can be used for different modern applications. 12 , 13 …”

“…In this method, Na + cations in sodium titanate nanotubes are replaced by different metal cations to form the desired metal-doped titanates, which can be used for different modern applications. 12,13 This work explores the effect of cation exchange in Na-TNTs with different transition metal ions on their dielectric properties, electronic structures, and optoelectronic properties. Nanotube morphology was chosen due to the catalytic activity associated with the tubular shape and the crystalline anisotropy, which motivated us to depict the existence of a net dipole moment along the tube axes.…”

“…The optical and catalytic properties of as-prepared nanotubes can be modified using the metal ion-exchange method. In this method, Na + cations in sodium titanate nanotubes are replaced by different metal cations to form the desired metal-doped titanates, which can be used for different modern applications. , …”