<span style="font-size:13.0pt;mso-bidi-font-size: 15.0pt" lang="EN-US">Electrical conductivity of cuprous bromide in the temperature range of 30-490 °C </span>

Abstract

The electrical conductivity (dc) of solid CuBr has been determined employing the cell configuration Cu/CuBr/Cu over a wide range of temperature (30 – 490 °C) which allowed the phase transformations: <img src='/image/spc_char/gamma2.gif' border=0>-CuBr ↔ β-CuBr and β-CuBr ↔ α-CuBr. With the measured conductivities, activation energy and pre-exponential factors have been evaluated over the studied range of temperature. Transport properties in the respective phases are discussed and compared with those reported in the literature. Though the order of magnitude of observed conductivity is same as that reported in literature, the observed values are higher than those reported earlier. The electrical conductivity of <img src='/image/spc_char/gamma2.gif' border=0>-CuBr increases rapidly with temperature, from 2.51 × 10^-3 Ω^-1m^-1 at 50 °C to 16.08 Ω^-1m^-1at 400 °C. After the first phase transition of <img src='/image/spc_char/gamma2.gif' border=0>-CuBr ↔ β-CuBr, the electrical conductivity attains a value of 148 Ω^-1m^-1 and increases further with increase in temperature. The conductivity increases by about 30 % on β-phase ↔ α-phase transition (maximum value 377.60 Ω^-1m^-1 at 487 °C). Activation energies for conduction of <img src='/image/spc_char/gamma2.gif' border=0>-CuBr are found to be 85.58 kJ mol^-1 (30-225 °C) and 145.35 kJ mol^-1 (320-380 °C) whereas for β-CuBr it is 22.45 kJ mol^-1 and for the superionic α-phase it is 2.38 kJ mol^-1.