Dielectric relaxation and complex electrical formulation studies of shockwave-treated ammonium dihydrogen phosphate crystals

Abstract

Ammonium dihydrogen phosphate (ADP) crystals have been grown by a slow evaporation technique. The grown crystals have been subjected to shockwaves of different fluences having Mach number 1.7. Grain growth due to the influence of shockwaves in ADP crystals has been inspected by scanning electron microscopy (SEM). Defects generated in the unit cell of ADP due to shock waves have been experimentally studied on the basis of photoluminescence. The influence of shockwaves on the dielectric, impedance, and modulus properties of ADP crystals has been comprehensively studied in the frequency range from 100 Hz to 10 MHz and the temperature range from 323 K to 373 K. Shockwave treatment improved the dielectric constant, ACconductivity, polarizability, and grain capacitance. It also reduced the grain resistance and the density of states at the Fermi level. The correlation barrier hopping (CBH) conduction mechanism has been studied for pristine and shockwave-treated ADP crystals over the temperature range considered. The presence of grains over the studied frequency range has been assessed by complex impedance spectroscopy and complex modulus spectroscopy. Both the pristine and shockwave-treated ADP crystals showed temperature-independent, non-Debye-type relaxation process. The activation energies of pristine and shockwave-treated ADP crystals obtained from the different formulations were in good agreement. The capacitance and conductance were in accordance with the dielectric results.