Halogen-Substituted Phenazine Cores Reduce Energy Losses and Optimize Carrier Dynamics in Tethered Acceptors for 19.8% Efficient and Stable Polymer Solar Cells

Tethered small-molecule acceptors (SMAs), featuring multiple SMA subunits connected to an aromatic core via flexible chains, effectively suppressing thermodynamic relaxation and enhancing stretchability in polymer solar cells (PSCs). However, these...