Molecularly Interlocked Interfaces Enable Record‐Efficiency Stretchable Organic Photovoltaics

Abstract The development of stretchable organic solar cells (s‐OSCs) demands concurrent breakthroughs in mechanical compliance and electronic properties, and the challenge is rooted in the intrinsic mechanical mismatch between organic semiconductors and metal electrodes. Here, this study proposes dual‐phase interface engineering strategies to reconcile these conflicting requirements through molecularly interlocked conductive elastomers. Dynamic stress dissipation through dynamic bond plasticity is achieved by embedding a 3D interpenetrating conducting elastomer network within the electron transport layer (ETL). The strategy creates gradient modulus interfaces through Ag coordination‐enabled nanocomposite bonding, suppressing crack propagation velocities and reduces the interfacial mechanical mismatch phenomenon. Eventually, the PCE of 19.58% is achieved on the small‐area flexible devices, which is one of the highest PCEs for flexible organic solar cells (f‐OSCs) to date. Notably, the stretchable devices retain over the PCE of 10% under 100% tensile strain, surpassing previous stretchable photovoltaic devices. To further validate the potential of this strategy for large‐area module applications, 25 cm 2 ‐based flexible and stretchable modules are prepared with PCEs of 16.74% and 14.48%, respectively. The work redefines material design rules for deformable electronics by establishing a generic mechanically adaptive framework that synchronizes interfacial dynamics across molecular to macroscopic scales.