Electron-Delocalized Thiophene-Amine Porous Organic Framework Cathode for Stabilizing High-Loading Aluminum Metal Batteries

Organic electrodes hold promise for sustainable, cost-effective, grid-scale aluminum metal batteries (AMBs) that store aluminum complex ions. However, most conventional organic polymers reported to date suffer from sluggish redox kinetics and structural collapse, which severely restrict the rate performance and cycling stability. Herein, we report a thiophene-amine porous organic framework (TA-POF) cathode that integrates dual redox-active N and S sites, large 1D channels, and an extended π-conjugated backbone. These structural advantages enable efficient electronic delocalization and rapid AlCl$_4$$^–$ ion diffusion. The resulting AMBs exhibit a high energy efficiency of 88.3% and outstanding long-term cycling stability, showing no degradation over 2000 cycles and offering an operational life that exceeds that of most AMB cathodes. Importantly, at a high areal loading of 6.9 mg cm$^{–2}$, the AMB still delivers 91% of the capacity obtained at low loading. Ex situ studies verify a reversible dual-site anion storage process. This work establishes thiophene-amine POF as a robust platform for designing durable, efficient, and sustainable AMBs.