Electrical properties of zinc sulfide and silver sulfide as binary salts in gel polymer electrolytes for quantum Dot-Sensitized solar cells

•MC:SN:co-ZnS-Ag2S:S GPEs with different mass fractions of ZnS:Ag2S were prepared and characterized.•The dielectric properties of MC:SN:co-ZnS-Ag2S:S GPEs have been investigated•MC:SN:(ZnS:Ag2S = 80:20):S GPE sample exhibits the highest ionic conductivity of 6.93 × 10-2 S.cm−1 and the lowest activation energy of 0.23 eV.•MC:SN:(ZnS:Ag2S = 80:20):S is also the most amorphous GPE.•FTO/ZnO-ZnFe2O4/CdS/MC:SN:(ZnS:Ag2S = 80:20):S GPE/Pt/FTO QDSSC was fabricated and characterized.