Figure 4. The solar cell structure of a) pristine PSCs, b) PSCs with nanopatterned TiO2 layer, c) PCBM-PSCs and d) PCBM-PSCs with nanopatterned TiO2 layer.
To have a better understanding regarding the dual effects of nanopatterning depth and wt% of PCBM on PSCs and the differences between each PSC, four types of PSCs were fabricated, as shown inFigure 4 . The fabricated PSCs were pristine PSCs, PSCs with nanopatterned TiO2 layer, PCBM-PSCs, and PCBM-PSCs with nanopatterned TiO2 layer. The best combination of nanopatterning depth (127 nm) and wt% of PCBM (0.10 wt%) that yielded the highest predicted ECE was selected as a reference to fabricate the PSCs.