3D Bimetallic Platinum‐Nickel Electrodes for Electro‐Oxidation of Glycerol at Ambient Conditions.

Partial electro‐oxidation using renewable electricity offers a sustainable route for valorizing glycerol, a major by‐product of biofuel production. This study introduces a bimetallic electrode with nanostructured platinum dendrites on nickel foam (Pt/NiF), achieving a peak geometric current density of 235 mA cm−2 and a Pt‐mass normalized current density of 3.71 AmgPt−1${\mathrm{A\ mg}}_{{\mathrm{Pt}}}^{ - {\mathrm{1}}}$ for glycerol electro‐oxidation at 0.92 V versus a reversible hydrogen electrode (RHE) in 3 m KOH electrolyte containing 1 m glycerol, outperforming most previously reported Pt‐containing catalysts. The Pt/NiF electrode demonstrates over 92% cumulative selectivity toward C3 products, with 64% selectivity for lactic acid at 0.65 V versus RHE over 5 h of testing. This research also highlights the role of chemical oxidation pathways (isomerization and rearrangements) in converting glycerol to lactic acid. After 5 h at 0.65 V versus RHE, the Pt/NiF electrode maintains 35% of its initial current density, plateauing at 12.2 mA cm−2 (0.15 AmgPt−1${\mathrm{A\ mg}}_{{\mathrm{Pt}}}^{ - {\mathrm{1}}}$), with performance loss likely due to surface poisoning by carbon‐based reaction intermediates/byproducts or passivating platinum (hydr)oxide species. These findings pave the way for developing low‐platinum group metal catalysts with high glycerol oxidation affinity and highlight the importance of considering chemical transformations during catalyst evaluation and reactor design. [ABSTRACT FROM AUTHOR]