Long time thermal annealing effects on the film morphology and performance of polymer solar cells with calcium electrode

Annealing time effect on the performance of polymer solar cells having active layers doped with hole-transporting material

“…In particular, the initial 2 min annealing made the biggest jump for J SC and V OC , which is in accordance with the trend of binary blend solar cells. [18][19][20] However, the up-and-down oscillation observed for the binary blend solar cells 18 was not measured for the present ternary blend solar cells but the slight slowdown trend in J SC and fill factor (FF) was found at around 10 min as shown in Figure 5. Thus we consider that the presence of TPD molecules might play a positive role in this continuous upward increasing of device performance though a marginal slow-down trend still existed.…”

Near‐Infrared Organic Phototransistors with p‐Channel Photosensitive Layers of Conjugated Polymer Composed of bis‐Octyldodecyl‐Diketopyrrolopyrrole and Benzothiadiazole Units

“…[48] As observed from the photoelectron (PE) yield spectrum in Figure 1d, the ionization potential of −5.21 eV was measured for the PODTPPD-BT film under ambient condition, which led to a highest occupied molecular orbital (HOMO) energy of −5.44 eV after calibration. [49,50] Based on the HOMO energy and the optical bandgap energy (E g = 1.21 eV) that could be obtained from the tauc plot of the PODTPP-BT film ( Figure S2, Supporting Information), the lowest unoccupied molecular orbital (LUMO) energy for the PODTPPD-BT film was calculated to be −4.23 eV (see the inset diagram in Figure 1d).…”

Initial Performance Changes of Polymer/Fullerene Solar Cells by Short‐Time Exposure to Simulated Solar Light

“…In particular, the increment became larger with increasing photon energy, indicating that zone 2 is more pronounced than zone 1. Considering that the zone 2 corresponds to photoelectrons from PCBM components, [30] the increased photoelectron yield in the zone 2 can be attributed to a marginal change of the surface composition of the blend film under illumination. In other words, after 11 h of exposure the fraction of PCBM at the surface of the blend film might be increased marginally, as observed in the case of over-annealing.…”