Synthesis, Characterization, Fast Ion Transport and Phase Transition in a [Ag2HgI4:0.x AgI] Type Superionic Mixed Composite Materials (x = 0.2, 0.4, 0.6 mol. wt. %)

Experimental investigations concerning the preparation and characterisation ofthe system [ag2hgi4:0.x agi] (x=0.2, 0.4, 0.6 mol. wt. %),, have been undertaken with aview to evaluate the transport properties of the mixed system and to identify the fast ionconducting compositions. powder samples of various compositions containing 0.2, 0.4 and0.6 mol. wt. % [ag2hgi4:0.x agi] (x=0.2, 0.4, 0.6 mol. wt. %), were synthesized by solidstate reaction. samples were analyzed using powder x-ray diffraction (xrd), differentialthermal analysis (dta) and thermo-gravimetric analysis techniques in order to determinetheir crystal structure and phase transition temperatures. these studies have revealed theformation of new substances having phase transition temperatures similar to that of agi.detailed electrical conductivity measurements carried out in the frequency range 100 hz-10 khz and over the temperature range 90°-170 °c by a gen rad 1659 rlc digibridgehave identified the best conducting composition namely 4 mol. wt.% [ag2hgi4:agi],exhibiting an electrical conductivity of 1.14×10-1 s cm-2 k at 393 k and an activationenergy of 1.6 ev for ag+ ion migration within the solid. the occurrence of fast iontransport due to silver ion migration in several compositions of the above mixed system hasbeen explained on the basis of “hard and soft acids and bases” principle and ion exchangechemistry.