Electrochemical properties of systems with rubidium-tungsten-oxide bronze

Single-phase rubidium-tungsten-oxide bronze of the composition Rb_0.3WO₃ with hexagonal syngony (a = 0.7387 ± 0.0004 nm, c = 0.7547 ± 0.0004 nm) is synthesized. The ionic constituent of the bronze conductivity, determined for the first time ever, is nearly three orders of magnitude as small as the electronic constituent and varies from 1.1 × 10^?2 to 2.7 × 10^?2 S cm^?1 at 30–84°C. The reversibility of the Rb_0.3WO₃/Rb₆La₂Si₆O₁₈ interface increases with the environment humidity. The exchange current is equal to 6.4 × 10^?4 A cm^?2 at a temperature of 30°C and a relative humidity of 58%. It is shown that the synthesized bronze may, in principle, be utilized in the role of a reference electrode in solid-state potentiometric sensors for carbon dioxide and hydrogen sulfide that would be capable of operating in natural conditions.