Ferroelectric Polarization Effects of Single-Atom Catalysts on Water Oxidation.

The oxygen evolution reaction (OER) performance of single-atom catalysts (SACs) heavily depends on their substrates. However, heterojunctions with traditional substrate materials often fail to provide the desired dynamic interface effects. Here, through a systematic study of the ferroelectric heterostructure InSe/C-N-M, the feasibility of using ferroelectric materials to achieve dynamic optimization of the OER activity on SACs is demonstrated. The ferroelectric InSe is confirmed to be an effective substrate for improving the stability of various SACs, supported by theoretical results of their negative formation energy and positive dissolution potential. Activity analysis indicates that among these InSe/C-N-M systems, the InSe/C-N-Ir can achieve near-ideal catalytic activities through polarization switching. It can unprecedentedly catalyze OER via a hybrid pathway of adsorbate evolution mechanism and O-O coupling mechanism under different pH conditions (from pH = 1 to pH = 13). Machine learning models have been developed to conduct feature analysis and make ultrafast predictions of OER activity, which identify that the interfacial charge transfer triggered by ferroelectric polarization is the key to fine-tuning the OER performance of SACs. This work provides a theoretical framework that utilizes ferroelectric polarization as a powerful approach to navigate the design of efficient SACs.