Photovoltaic characterization. We performed current density-voltage (J-V) curve measurements of 9.46 cm 2 devices with illumination from a Xe lamp (Abet Sun 2000 Solar Simulator, AAB class) with 1 sun intensity (100 mW cm -2 , AM 1.5G), calibrated with a reference Si diode. The device performance was recorded with a Keithley 2636A source meter, controlled by a LabVIEW program. The J-V curve is obtained by scanning from 1.2 to -0.1 V (reverse scan) and from -0.1 to 1.2 V (forward scan) with a step size of 20 mV and a delay time of 100 ms. J-V curves of small-scale devices were measured in air using a custom-built Cicci setup, with a forward/reverse scan rate of 200 mV s -1 . All solar cells were measured under the standard 1 sun AM 1.5G spectrum using a Sunbrick Base-UV large area AAA LED solar simulator (G2V), with a spectral mismatch of <5%. The system was calibrated separately using both a silicon KG5 filter reference cell (RERA Solutions, model number: RK5N3199) and an Avantes (AvaSpec-ULS2048CL-EVO-FCPC) spectroradiometer.