Hydraulic pressure and temperature effects on the structural, morphological and electrical properties of SeO2 powders

Abstract

Herein, powders of SeO2 are subjected to hydraulic pressure in the range of 1.0–12 MPa and heating cycles in the range of 290–383 K. The pressure and temperature efects on the crystalline nature, plane orientations, structural parameters, surface morphology, composition, electrical resistivity, capacitance spectra and conductance spectra are explored. It is observed that hydraulic pressure value of 6.0 MPa is a critical value at which the tetragonal SeO2 grains prefer (020) plane orientation over (011) planes. The (020) plane orientations resulted in remarkable changes in the lattice parameters, structural parameters, electrical resistivity, capacitance and conductance spectra. In addition, the heating and cooling cycles of the samples pressed at 10 MPa have shown that the transition of the planes is permanent. The heated and cooled pellets displayed resonance–antiresonance in the capacitance spectra near 0.43 GHz. The resonance–antiresonance phenomena are accompanied with negative conductance effect near 0.43 GHz. The enhancements in the properties of SeO2 powders that are achieved via pressure and temperature effects make them appropriate for electronic circuit technological applications.