The stability of CsH5(PO4)2-based composites was investigated in detail.
Porous silica, SiP2O7, and sol–gel derived silica glasses were tested as matrices.
CsH5(PO4)2/SiO2 composites were not stable during repeated heating and cooling.
CsH5(PO4)2/SiP2O7 composites absorbed a large amount of water at low temperatures.
CsH5(PO4)2 doped silica glasses exhibited extremely stable conductivity.