Porous silica alcogel matrix entrapped with liquid electrolyte: Ionic conductivity and growth of whiskers

Highly porous silica alcogel, with pores entrapped with liquid electrolyte solutions of KH₂PO₄, has been successfully prepared by hydrolysis and polycondensation of tetraethylorthosilicate (TEOS) giving interesting “solid-liquid electrolyte composites”. The entrapped liquid electrolyte solution gives high liquid-like ionic conductivity (10⁻⁵ S·cm⁻¹). Further, on storage the entrapped solution slowly reaches the surface pore-heads where it evaporates resulting in the growth of long crystalline whiskers. Higher relative humidity (>60%) slows down the evaporation and has been found to be favorable for whisker growth.