Phase-regulated built-in electric field intensity mediates reconstructing for efficient water oxidation

The uncontrollable dynamic surface reconstruction of oxygen evolution reaction (OER) catalysts poses a significant impact on the activity and stability of the catalysts. To tackle this issue, a phase-controlled strategy is utilized to fabricate various CoxSy/layered double hydroxides (LDH) heterojunction with adjustable built-in electric field (BIEF) intensity. The BIEF formed at the interface leads to an accumulation of OH- on the electron-deficient region of CoxSy side, facilitating its reconstruction and exposing more active sites. Furthermore, it enhances the bond energy of M-O in the electron-rich LDH, alleviating LDH reconstruction and enhancing stability. The asymmetrical distribution of interface charges induced by the BIEF effectively modulates the d-band center of the metal sites, optimizing the adsorption/desorption of reaction intermediates. As a result, the designed Co3S4/LDH demonstrates outstanding OER activity and stability. This study introduces a novel approach to regulate the reconstruction of heterogeneous catalysts by leveraging interface effects driven by the BIEF.