Hierarchical Ru<sup>0</sup>/Ru<sup>δ+</sup>/Al<sub>2</sub>O<sub>3</sub> electrocatalyst enabling phenolic contaminant-to-chemical conversion.

Wang, Renyu; Zhang, Gong; Liu, Lizhe; Ji, Qinghua; Lan, Huachun; Qu, Jiuhui; Liu, Huijuan · Nat Commun · 2025

basic_science · Level V

Where this comes from

Abstract

Valorizing phenol in wastewater to cyclohexanol via electrochemical hydrogenation (ECH) offers a promising strategy for advancing a circular economy that shifts from pollutant control to resource recovery, but remains challenged by the absence of efficient and selective catalysts in complex wastewater matrices. Herein, we report a hierarchical Ru<sup>0</sup>/Ru<sup>δ+</sup>/Al<sub>2</sub>O<sub>3</sub> catalyst with coupling multi-level electronic state to improve the phenol ECH performance. The metal-semimetal-insulator hierarchical interface effectively induces the integration of H* evolution and phenol activation, and the unsaturated Ru-O coordination formed by precise anchoring of Ru on Al<sub>2</sub>O<sub>3</sub> lowers the reaction energy barrier, achieving a 4.3-fold increase in the reaction rate over that on the pristine Ru catalyst. Consequently, the ECH process applied to actual phenol-containing wastewater demonstrates a stable cyclohexanol selectivity of approximately 80% for over 120 h, making it more economically feasible and environmentally beneficial than the conventional adsorption-Fenton oxidation treatment. Our work provides valuable guidance for wastewater treatment from environmental burden to sustainable recovery.