Towards the maximum efficiency design of a perovskite solar cell by material properties tuning: A multidimensional approach.

To obtain significant increases in the Power Conversion Efficiency (PCE) of solar cells, we argue that the substitution of the state-of-the-art one- and two-dimensional cell optimizations, by the simultaneous improvement of multiple material properties is of substantial advantage. In this context, researchers should know, which combined material properties and cell design parameters result in the highest efficiency increase. For the same objective, it is also of importance to know, which ideal relationships in-between these variables have to be adjusted. Such knowledge becomes available by simulations and numerical optimizations, which we present for a Perovskite Solar Cell (PSC) in a hypercube space of model variables. We prove that its PCE increases principally because of the nonlinearities inherent to its mathematical model, and therefore, we elucidate the importance of the multidimensional variable improvements in the PSC’s optimization. We increased the PCE to a value of at least 27.6% by simultaneous improvements of the cell’s material properties, and light trapping, for a large range of absorber layer thicknesses, from t₀ = 160 to 400 nm. The lower thickness results in a significant reduction of the device’s Pb content.