Figure 1: Effect of the charge-carrier mobility on the JV characteristics.

(a) JV curves for six different charge-carrier mobilities. Thin lines with symbols show drift-diffusion simulations with the parameters in Table 1, while thick lines are the results of our analytical approximation. (b,c) show the corresponding energy diagrams under short-circuit conditions (V_ext=0 V) for μ=1 and 10⁻⁶ cm²(Vs)⁻¹, respectively. (d) Internal voltage V_int (left y axis) versus external voltage V_ext as extracted from the simulated JV curves with equation (6) for three different mobilities, compared with the Shockley equation (dotted line). The right y axis shows the corresponding recombination rate R. All graphs correspond to an illumination intensity of ‘1 sun’.