Achieving Distributed and Flexible Hydrogenation of Aromatics with Crude Hydrogen from Electrolyzers

Abstract

The efficient production, storage, and utilization of green hydrogen produced from renewable energy sources are crucial for developing a low-carbon energy system. However, the transition to sustainable chemical engineering still faces significant challenges in replacing fossil fuel-dependent, energy-intensive processes with flexible alternatives that directly utilize green hydrogen under mild conditions. Here, we report ensemble-engineered Pt-surface-enriched Au–Pt bimetallic catalysts for aromatic hydrogenation and renewable-H2 storage. DFT calculations and in situ characterization reveal that a five-Pt-atom surface ensemble enables the balanced co-adsorption of benzoic acid and H2, while adsorbed aromatic substrates anchor the surface Pt ensembles and suppress H2-induced Pt migration, thereby imparting a substrate-anchored stabilization of the active Pt ensembles. The optimized Pt3Au7/TiO2 catalyst achieves a TOF of 5250 h–1 for benzoic acid hydrogenation at 60 °C and 1 bar H2, more than one order of magnitude higher than any catalyst reported for this reaction at atmospheric H2 pressure. The Pt5Au5 catalyst, selected as a balance between mass-specific productivity and precious-metal inventory, enables the production of cyclohexane-based polymer monomers and the solvent-free hydrogenation of liquid organic hydrogen carriers, and delivers a cumulative TON exceeding 79,000 over 42 days of continuous operation using unpurified low-pressure crude hydrogen from a photovoltaic-electrolysis-hydrogen system, advancing the practical application of green hydrogen in chemical manufacturing.