Contour map of JSC-AVT as the functions of the refractive index and layer thickness of the double layer OCL, calculated for n1 and n2 over the refractive index range from 1.0 to 3.0, and d1 and d2 over the thickness range from 0 to 200 nm. The data points, for example, the circle, square, star and triangle symbols, in the contour map are the JSC and AVT values calculated for the control cell without OCL, and the ST-OSCs with different OCLs of LiF (150 nm)/MoO3(100 nm) (OCL1), Na3AlF6(170 nm)/ZnS (110 nm) (OCL2), and ZnS (30 nm) (OCL3). The green arrow indicates the possible materials choices in the double layer OCL for realizing simultaneously a high JSC and a high AVT in the ST-OSCs.
