The roles of acceptors in the thermal-degradation of P3HT based organic solar cells

Unveiling the thermal stability of diketopyrrolopyrrole-based terpolymers: a key element for enhanced efficiency and stability of organic solar cells

“…These results suggest that thermal annealing enhanced the phase segregation, probably by means of the crystallisation of terpolymer chains and PC 71 BM aggregation. 9,51,54,55 Similar results with P3HT:PCBM blends were observed by Yang et al 56 and Hoppe et al 57 Using TEM and SEM they demonstrated that thermal degradation leads to the crystallisation of P3HT chains via stacked coplanar conjugated segments and dispersion of PCBM molecules forming large aggregates. A detailed study of the thermal annealing effect on PCBM aggregation was also reported by Kiel et al 55 Based on their neutron reflectivity results, they showed that upon annealing, the PCBM concentration increased at the sample-air interface with little change at the buried interface of the substrate and blend.…”

“…Similarly, the phase segregation between PC 71 BM and P3HT was also reported to drastically reduce the performance of the device. 54 After 3 and 24 h of thermal annealing, the active layer based on P1 displayed a more stable morphology compared to P2-and P3based devices, characterised by better intermixing between the donor and acceptor phases and reduced domain sizes. The degradation of the film containing P2, which contains a similar ratio of the two acceptors, was faster than that of the film containing P3 which has the highest FTAZ concentration.…”

Enhancing the Performance of Wide-Bandgap Polymer-Based Organic Solar Cells through Silver Nanorod Integration

“…It should be noted that recent studies indicate that the mobility of polymer solar cells decreases at large applied electric fields due to the negative values found at the field activation factor. 34 The fitting results of the SCLC are displayed in Figure 6b, and the results are summarized in Table 3. The results demonstrate that the zero-field mobility of the reference device was almost doubled when the optimum concentration of Ag-NRs (1%) was embedded in the active layer.…”

“…ε = 3 and ε o = 8.854 × 10 –12 F/m are the dielectric constant of the photoactive layer and the free space permittivity, respectively, while μ o and γ are the zero-field mobility and field activation factors, respectively. It should be noted that recent studies indicate that the mobility of polymer solar cells decreases at large applied electric fields due to the negative values found at the field activation factor …”

“…It should be noted that recent studies indicate that the mobility of polymer solar cells decreases at large applied electric fields due to the negative values found at the field activation factor. 34 …”