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

Abstract

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.