Fig. 6: Fill factor loss analysis of the optimized TPC solar cell.

In this loss analysis, the two-diode model of solar cells is used, which includes two diodes with saturation current densities J01, J02 and ohmic resistors Rs, Rsh in series and shunt to the diodes, respectively. The stack in red is the actual FF (80.9%) of the optimized solar cells, the stacks represent the FF loss due to the series resistance (2.96%, in blue), the shunt resistance (0%, in purple) and the J02 recombination (1.11%, in yellow), respectively. The stack in blue shows the FF assuming the absence of Rs, Rsh and J02.