Fig. 4. Simulated JV characteristics of different D–A systems.

Simulated (dashed lines) compared to experimental (symbols and solid lines) for devices based on: a TPDP:C₆₀ at three representative concentrations and b ZnPc:C₆₀ (50 wt%). Also shown in (b) are the JV characteristics for SRH process in the absence of Poole-Frenkel effect and bimolecular generation over E_CT. Inset in (a) shows the reverse region in detail and in (b) a schematic representation of a mid-gap trap distribution in the donor–acceptor system. Mobilities and recombination rates were optimized to achieve a good agreement with the experimental data (see Supplementary Table 6). c Schematic representation of the energy level of the three systems showing an extraction and an injection barrier. A barrier-free system is also shown. d Activation energy for TPDP:C₆₀ extracted from temperature-dependent JV measurements. The current was measured at temperatures varying from 223.15 to 303.15 K with ΔT = 10 K. For each bias, the logarithm of the current was plotted versus 1/T, and E_a was extracted from the slope of the curve. The fit for V = −1.5 V is shown in Supplementary Fig. 21.