Efficient Ag8GeS6 counter electrode prepared from nanocrystal ink for dye-sensitized solar cells†
Ternary metal sulfides could provide more alternatives and tune physicochemical properties due to the presence of two cations. However, only Co/Ni-based ternary sulfides have been explored as counter electrode (CE) materials for dye-sensitized solar cells (DSSCs). Herein, CEs fabricated using Ag8GeS6 nanocrystal ink exhibited efficient electrocatalytic activity in the reduction of I3− to I− in DSSCs. The DSSC with the Ag8GeS6 CE displayed a higher power conversion efficiency of 8.10% than that with the Pt CE (8.02%). Moreover, the devices also showed the characteristics of fast activity onset, high multiple start/stop capability and good irradiation stability. The results indicated that the developed Ag8GeS6 CE could be a promising alternative to Pt CEs in DSSCs.