Dye-sensitized solar cells utilizing aurum-palladium bimetal film counter electrode

This work is concerned with the improvement of dye-sensitized solar cell efficiency by incorporating aurum into palladium which serves as a counter electrode (CE) for the device. The CE has been prepared via the liquid phase deposition (LPD) technique. The effect of the concentration of aurum (III) chloride trihydrate (HAuCl₄.3H₂O) on the properties and the performance of the device has been studied. The sources of palladium and aurum are potassium hexachloropalladate (K₂PdCl₆) and HAuCl₄.3H₂O, respectively. A dominant phase of Au–Pd exists in the sample. The morphological shape of AuPd is a truncated nanohexagon plate. The particle size of AuPd increases with the concentration of HAuCl₄.3H₂O, but its crystallite size decreases until an optimum concentration of 0.5 mM. The device employing AuPd CE with 0.5 mM HAuCl₄.3H₂O yielded the highest efficiency of 6.69%. This is because this device possesses the highest coverage area, highest particle density, biggest particle size, smallest crystallite size, highest IPCE, lowest R_s and R_ct, longest τ, highest J_pc, J_o, and J_lim. In conclusion, AuPd is found as a suitable CE candidate in efficient DSSC.