Unraveling the Stretch‐Induced Microstructural Evolution and Morphology–Stretchability Relationships of High‐Performance Ternary Organic Photovoltaic Blends

Abstract

The stretchability and stretch‐induced structural evolution of organic solar cells (OSCs) are pivotal for their collapsible, portable, and wearable applications, and they are mainly affected by the complex morphology of active layers. Herein, a highly ductile conjugated polymer P(NDI2OD‐T2) is incorporated into the active layers of high‐efficiency OSCs based on nonfullerene small molecule acceptors to simultaneously investigate the morphological, mechanical, and photovoltaic properties and structural evolution under stretching of ternary blend films with various acceptor contents. The structural robustness of the blend films is indicated by their stretch‐induced structural evolution, which is monitored in real‐time by a combination of in situ wide/small angle X‐ray scattering. It is found that adding the soft P(NDI2OD‐T2) can enhance the stretchability and structural robustness of ternary blend films by more entangled chains and tie chains to dissipate strain. Furthermore, the stretchability of the ternary blends can be superbly predicted by a 3D equivalent box model. This work provides instructive insight and guidance for designing stretchable electronics and predicting the stretchability of multicomponent blends.

Organic and quantum dot hybrid photodetectors: towards full-band and fast detection

“…Nevertheless, QD photodetectors generally present the inferior mechanical performance, which places great restrictions on their applications in wearable electronics. The great flexibility of organic semiconductors 103 may offer promising roads to enhance the mechanical performance of QPDs via the hybrid strategy. Moreover, our recent work has demonstrated that a promising elastomer can further enhance the mechanical performance of organic semiconductors, which is favorable for developing stretchable electronics.…”

Toward efficient hybrid solar cells comprising quantum dots and organic materials: progress, strategies, and perspectives

“…We believe that the above research directions can enable the further performance and stability improvement of hybrid solar cells and thereby advance the progress toward commercialization. 223…”

Synergistic optimization of mechanical and photovoltaic properties in ternary organic solar cells from a two-donor polymer blend

“…Yet, the prediction of mechanical properties of ternary blend lms is much more complicated, and prior efforts have met with only limited success. 22 Particularly, the theoretical understanding of new ternary blends based on dual donor polymers has not been This journal is © The Royal Society of Chemistry 2023 achieved thus far. Herein, we attempted to ll this gap by applying the knowledge of classic polymer mechanics.…”

“…We noted that the equivalent box model (EBM) was used to predict the elastic modulus of multicomponent polymer systems. 22,[54][55][56][57][58] This motivated us to understand the ternary OSC systems with the EBM. As shown in Fig.…”

“…As ternary OSCs reduce the fabrication complexity of the tandem structure and the production cost, the ternary mixing strategy has received growing attention and is considered to be the most effective strategy to overcome the drawbacks of the binary blend of polymer and organic small molecule components. [8][9][10][11][12][13][14][15][16][17] Taking the high-efficiency PM6 and N3 binary system 18 as an example, several research groups [19][20][21][22][23][24][25] applied the ternary mixing strategy to produce improved performance and even record-high efficiency OSCs in the last few years. In a previous study, Peng et al 20 brought a common fullerene acceptor as the third component to modulate the mechanical, morphological, and photovoltaic properties of the PM6:N3 blend.…”