Intrinsically Stretchable Fiber‐Shaped Solar Cells with Polymer‐Based Active Layer

Abstract

Fiber‐shaped organic solar cells (FOSCs) with intrinsic stretchability show great potential in stretchable and wearable electronics applications. However, limited by the poor stretchability of small molecule semiconductors, the stretchability of FOSCs is still not satisfied. Polymerized nonfullerene acceptors with excellent photovoltaic performance are a promising strategy for preparing stretchable semiconductors and photovoltaics. Herein, an efficient polymer‐based bulk‐heterojunction blend is adopted as the photoactive material of the stretchable all‐polymer FOSCs. The fabricated all‐polymer FOSCs show superior intrinsic stretchability that remains more than 90% of the initial efficiency under the stretch strain of 50% and maintains stable performance even when undergoing hundreds of stretching–releasing cycles. By adding the third component of polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene (SEBS) elastomer, the stretchable all‐polymer FOSCs can endure the ultrahigh stretch strains over 80%. This study demonstrates the superior mechanical properties of the all‐polymer FOSCs and the simple yet effective strategy of SEBS additive to enhance stretchability.

Advances in Smart Photovoltaic Textiles

“…The device fabrication and configuration are the same as in coaxial-type SCs, but the exterior electrodes are twisted around in a spring form on HTL/ETL layers, giving additional room for light transmission, Figure b. , These twisting-type SCs are significant to achieve high electrical performance due to the choice of sophisticated electrode materials and refined fabrication process. Furthermore, these fiber-based SCs are advantageous for DSSCs, due to their use of a liquid electrolyte, as the electrode makes full contact with the electrolyte and forms a better interface between them. , Highly stretchable and flexible fiber-shaped OSCs, configured in a twisted design, have been demonstrated as a sustainable option for wearable applications. , However, it is important to note that the shadow cast by the external electrode over the functional layer, as well as the longer charge carrier distance, can reduce the SCs performance of twisting-type SCs. In general, the thickness of the electrode fiber directly impacts the performance of twisting-type SCs.…”

“… 208 , 209 Highly stretchable and flexible fiber-shaped OSCs, configured in a twisted design, have been demonstrated as a sustainable option for wearable applications. 210 , 211 However, it is important to note that the shadow cast by the external electrode over the functional layer, as well as the longer charge carrier distance, can reduce the SCs performance of twisting-type SCs. In general, the thickness of the electrode fiber directly impacts the performance of twisting-type SCs.…”