Lignin‐Metal Supramolecular Framework Strategy of Self‐Healing Carbon‐Coated CoRu Alloy Nanocatalyst for Efficient Overall Water Splitting

Abstract

AbstractCommon precursors for carbon materials typically include petroleum‐based polymers or MOF materials. However, these materials often encounter challenges such as metal aggregation, high cost, and metals leaching. In this work, a novel of approach lignin‐metal supramolecular framework complex (MSF@Lignin) is introduced. These complexes are formed through oxidative ammonolysis of lignin (OAL) to synthesize a nitrogen‐doped carbon‐encapsulated CoRu nanocatalyst (CoRu@OALC) via in situ carbonization. CoRu@OALC exhibited exceptional performance in both HER (90 mV) and OER (200 mV) at the current density of 10 mA cm−2, with an overall water splitting voltage of 1.5 V and outstanding stability under high density. During the pyrolysis process, metal became encapsulated by lignin‐derived carbon, occurring within the temperature range of 600–700 °C. In the catalytic process, active sites are primarily located within the defects in lignin‐derived carbon, showcasing a unique “self‐healing” phenomenon within the carbon layer. Oxygen‐containing intermediates (*OH, *O, and *OOH) facilitated the reconstruction of defects on the carbon layer, while the hydrogen‐containing intermediates (*H) contributed to the reappearance of a defect‐rich structure.