Tuneable C3 product selectivity of glycerol electrooxidation on cubic and dendritic Pt nanocatalysts

Abstract

Glycerol, being an abundant and cheap by-product of biodiesel production, has emerged as a raw material that can be recycled into value-added compounds. In the present study, Pt nanoparticles of cubic (Pt_CUBE) and dendritic (Pt_DEND) morphologies were investigated as catalysts for the glycerol electrooxidation reaction (GEOR) at 20 °C. To optimise the electrocatalytic performance and GEOR selectivity towards three-carbon (C3) products, namely lactate, glycerate, and tartronate, the effects of morphology, electrolyte composition, and applied potential were studied. At low glycerol concentrations, C–C bond cleavage was more favoured, especially on Pt_DEND. Both Pt_CUBE and Pt_DEND showed high C3 product selectivity up to 91% at 0.67 V vs. RHE, with lactate reaching a maximum selectivity of 68% on Pt_CUBE, which also exhibited the best mass and specific activities compared to Pt_DEND.