Modulating Hydrogen Adsorption by Unconventional p-d Orbital Hybridization over Porous High-Entropy Alloy Metallene for Efficient Electrosynthesis of Nylon-6 Precursor.

Renewable electricity driven electrosynthesis of cyclohexanone oxime (CHNO) from cyclohexanone (CHO) and nitrogen oxide (NO) is a promising alternative to traditional environment-unfriendly industrial technologies for green synthesis of CHNO. Precisely controlling the reaction pathway of the CHO/NO-involved electrochemical reductive coupling reaction is crucial for selectively producing CHNO, which is yet still challenging. Herein, we report a porous high-entropy alloy PdCuAgBiIn metallene (HEA-PdCuAgBiInene) to boost the electrosynthesis of CHNO from CHO and nitrite, achieving a high Faradaic efficiency (47.6 %) and almost 100 % yield under ambient conditions. In situ Fourier transform infrared spectroscopy and theoretical calculations demonstrate that unconventional orbital hybridization between d-block metals and p-block metals could regulate the local electronic structure of active sites and induce electron localization of electron-rich Pd sites, which tunes the active hydrogen supply, facilitates the generation and enrichment of key intermediates NHOH* and CHO*, and efficiently promotes their C-N coupling to selectively produce CHNO.