Electrocatalytic hydrogenation of biomass-derived phenol represents a sustainable alternative route to produce value-added chemicals such as cyclohexanone by replacing current energy-intensive thermo-catalytic processes. However, to date, the current densities of selective electrocatalytic phenol-to-cyclohexanone conversions are significantly lower than the requirements for industrial applications. Herein, we report a platinum-palladium (PtPd) alloy electrocatalyst, exhibiting cyclohexanone production with 51% Faradaic efficiency and 88% selectivity at an industrial-relevant current density of 565 mA cm-2 under -0.40 V versus reversible hydrogen electrode. Mechanistic studies indicate that the Pt sites catalyze active hydrogen species generation, which experience spillover to Pd, while Pd sites are responsible for phenol adsorption and hydrogenation, cooperatively promoting cyclohexanone production via a non-competitive Langmuir-Hinshelwood mechanism. This work provides guidelines for the rational design of efficient electrocatalytic hydrogenation catalysts toward biomass upgrading at industrially relevant current densities.
Liu et al. (Mon,) studied this question.