1 research outputs found
Unraveling the Characteristic Shape for Magnetic Field Effects in Polymer–Fullerene Solar Cells
Spin-dependent
effects in organic solar cells (OSCs) are responsible
for tuning the electric current when an external magnetic field is
applied. Here, we report the magnetic field effect (MFE) on wide-bandgap
(WBG) solar cells based on the polymers PBDTÂ(O)-T1 and PBDTÂ(Se)-T1
blended with PC<sub>70</sub>BM. Furthermore, we propose an experimental
method based on the electrical transport (<i>i</i>–<i>V</i>) measurements to unveil the negative magneto conductance
(MC) at small bias. The observed curves in a double-logarithmic scale
display a particular S-like shape, independent of the OSC power conversion
efficiency (PCE) or MC amplitudes. Additionally, from the slope of
the S-like shape curve, it is possible to identify the fullerene concentrations
that would result in the minimum MC and the maximum PCE. Our work
opens up a door to find more patterns to describe MFE and PCE in polymer–fullerene
solar cells, without the application of external magnetic or luminous
sources