Nonstationary processes in an electric field during coadsorption of gold and alkali metals on tungsten

The processes induced by a strong electric field in the “tungsten-gold-alkali metal” adsorption systems are studied. Field desorption of K⁺ and Cs⁺ ions initiates nonstationary processes involving ion current pulsations and periodic displacements of desorption regions under constant experimental conditions. The observed effects are explained as resulting from the processes of (i) formation of an alkali-metal-gold film exhibiting properties of a wide-band-gap semiconductor, (ii) breakdown and restoration of this film in an electric field, and (iii) accumulation and relaxation of the electric charge.