An investigation of modified AgI solid electrodes containing the homopiperazinium cation—I. Synthesis and characterization

Abstract Homopiperazinium and N, N, N′, N′-tetramethylhomopiperazinium diiodide (briefly designated as HI 2 and TMHI 2 ) have been synthesized and characterized by infrared spectroscopy and proton magnetic resonance spectroscopy. The two diazonia diiodides were reacted with silver iodide in concentrations ranging from 75 to 95 equivalent I − of AgI. In both HI 2 -AgI and TMHI 2 -AgI systems, the study of the total electrical conductivity with respect to temperature shows that the Arrhenius equation is obeyed. At 25°C, the maximal conductivity is reached for an equivalent content of 85% in the HI 2 -AgI system with a value of 0.003 (ohm cm) −1 . For the TMHI 2 -AgI system a dissymetric composition dependence of the electrical conductivity is observed around a main maximum at 90% AgI content corresponding to a 0.027 (ohm cm) −1 conductivity. Existence in this system of a second electrolyte phase around a 77.5–80% composition in AgI is sustained by electrochemical conductivity measurements and an independent X-ray powder diffraction study.