Establish Interpenetrating Network Structure by Controlling Phase Separation

In the following, we show in detail the strategies to improve the performance of all-polymer photovoltaic cells, which is directly related to the nanostructures of phase separation in active layer, in four aspects (i) Establish interpenetrating network structure by controlling phase separation, (ii) control the domain size and purify the domains, (iii) adjust the diffused structure at the interface between donor and acceptor, (iv) and construct the relationship between film morphology and device performance. 

1 Establish Interpenetrating Network Structure by Controlling Phase Separation 

The bicontinuous pathways formed by donor and acceptor materials in OSCs will ensure the separation of charge-transfer 

Up to now, the study about phase-separation theory is mainly focused on amorphous/amorphous polymer blend and crystalline/amorphous polymer blend models. There is still lack of systemically theoretical guidance and support for crystalline/crystalline polymer blend models. Therefore, the establishment of the phase-separation theory 

0% [129]. Using a cosolvent is another effective method to control film solidification. Zhou et al. found that the device elRciency could be improved by incorporation of chloroform into toluene. When chloroform was introduced, the movement time of polymer molecules decreased and the interpenetrating morphology with small domain size was formed, which led to the improvement of PCE from 1.85 to 2.23% [130]. 

---