Organic-inorganic hybrid interfaces with π-d electron coupling for preventing metal and sulfur leaching toward enhanced oxygen evolution reaction

Transition metal sulfides (TMSs) catalysts with high catalytic oxygen evolution reaction (OER) activity have been extensively studied, especially Fe and Co-based sulfides. Fe and Co active sites with a strong synergistic effect, which can adjust the electron density distribution and effectively improve the electrocatalytic OER activity. However, TMSs have poor stability in alkaline environment caused by metal ions and sulfur elements are facilitated to dissolve. In this work, TMSs was modified by polyaniline (PANI) to inhibit the precipitation of iron, cobalt, and sulfur elements and enhance its stability under alkaline conditions. Moreover, π-d structure can also be formed by the coating of PANI, which can further adjust its own electronic structure on the basis of stabilizing the TMSs structure, so as to improve the electrochemical performance, rendering them to stably operate at harsh environment for more than 90 h. These findings offer new guidance for improving the electrocatalytic stability of TMSs.