Hydrothermal synthesis of doped lanthanum zirconate nanomaterials and the effect of V–Ge substitution on their structural, electrical and dielectric properties

• Hydrothermal method has been successfully employed to synthesize the zirconates.
• XRD confirmed the formation of required phase.
• Increased electrical resistivity makes these materials useful for microwave devices.
• Dielectric parameters of zirconates decrease with increasing frequency.
• Dielectric constant decreases with increasing substituents concentration.

A hydrothermal method was successfully employed for the synthesis of a series of vanadium and germanium co-doped pyrochlore lanthanum zirconates with composition La2−xVxZr2−yGeyO7 (where x, y = 0.0, 0.25, 0.50, 0.75 and 1.0). The XRD and FTIR analyses confirmed the formation of single phase except vanadium and germanium substituted samples and the crystallite sizes are in the range of 7–31 nm for V3+–Ge4+ substituted samples. The theoretical compositions are confirmed by the ED-XRF studies. The room temperature electrical resistivity increase with the substituents concentration which suggests that the synthesized materials can be used for microwave devices as such devices required highly resistive materials. Dielectric properties were measured in the frequency range of 6 kHz to 1 MHz. The dielectric parameters decrease with increase in frequency. The DC resistivity data is in good agreement with the dielectric data.

Variation of dielectric constant with frequency for all the synthesized materials.Figure optionsDownload as PowerPoint slide