Polymer-Wrapped Chiral Single-Walled Carbon Nanotubes Enable 20% Efficiency Organic Solar Cells and Broadband Photodetectors.

Obtaining a broadened optoelectronic response while maintaining a low photovoltage loss is a critical challenge for organic solar cells (OSCs). Infrared-responsive chiral single-walled carbon nanotubes (SWCNTs) could address this, yet their application is hindered by complex purification and aggregation. Here, we disperse SWCNTs in a high-quantum-yield wide-gap polymer, F8BT, to create an F8BT@CNT(10,5) composite dopant. This dopant broadens the spectral response, promotes energy transfer, refines the phase morphology of donor-acceptor heterojunctions, and synergistically enhances charge transport while suppressing nonradiative and bimolecular recombination. The strategy is general, achieving a 20.10% PCE and a low nonradiative loss of 0.182 eV across various OSC systems. Beyond photovoltaics, it enables high-sensitivity organic photodetectors for precise, real-time heart rate monitoring. This work highlights the potential of polymer-wrapped chiral CNTs to improve organic optoelectronic devices for energy conversion and sensing.