Highly conductive hexaazatrinaphthylene-based salphen organic frameworks with atomically dispersed dual-metal sites for efficient electrochemical oxygen evolution

The 2D conductive porous organic frameworks (POFs) with single metal sites are expected to be ideal electrocatalysts. However, developing POFs with multi-metal sites to boost their activities remains a formidable challenge. Herein, we report the synthesis of hexaazatrinaphthylene-based salphen organic framework (HATN-SOF) with two different coordination sites for atomically dispersion of nickel/iron ions. Due to the high loading active metal sites, the synergy between Ni/Fe ions, and the high bulk conductivity of 0.144 S/m, the bimetallic NiFe-HATN-SOF showed high electrochemical oxygen evolution activity with a low overpotential of 259 mV at 10 mA cm−2. The mass activity and turnover frequency value reach 1304 mA/mg and 0.193 s−1 respectively at an overpotential of 300 mV, which are more than 20-times larger than those of the monometallic HATN-SOFs and of the benchmark RuO2. The research offers a new platform for rational design of bio-inspired heterobinuclear electrocatalysts with customized microenvironments for oxygen electrocatalysis.