Nanostructured TiO2 and ZnO solar cells using CdS as sensitizer: Stability investigation

Exploring quantum dots or nano-sized particles of CdS as an alternative sensitizer for organic dye in dye sensitized solar cells have attracted great interest due to the high cost and the UV instability of the organic dye. In this work, a 2.46% (V_oc=0.69 V, J_sc= 6.54 mA/cm², F.F. = 0.55) CdS sensitized nanoparticle TiO₂ solar cell is achieved under AM 1.5. The control sample of N3 dye sensitized TiO₂ solar cell has efficiency of 7.88%. However, the CdS sensitized TiO₂ cell degrades rapidly even under dark environment. Replacing TiO₂ with ZnO can increase the CdS sensitized solar cell stability. In addition, a solid state CdS sensitized DSSC is fabricated as another approach to improve cell stability.