Perovskite Oxides as Electrocatalyst for Glycerol Oxidation.

Glycerol is a co-product from Biodiesel production with high abundance and low market price. Its transformation into valuable products or as an alternative source of energy has driven the search for selective catalysts. Herein we present the first findings of perovskites as electrocatalysts for glycerol electrooxidation (GEOR). Alternatively to Pt and Pd based catalyst, perovskite oxides (LaNiO₃ and LaCoO₃) demonstrated high catalytic performance with faradaic currents of ca. 18 mA mg^-1 at potentials higher than 1.6 V vs. RHE. Consecutive potential cycles exhibited the LaCoO₃ perovskite resistant to poisoning during GEOR. Based on FTIR and online HPLC experiments the GEOR on perovskite oxides yields formic acid and glycolic acid as final products, with no signal of CO₂ formation. Our results thus indicate that perovskites can be considered as an alternative for selectively oxidize glycerol, opening the door for a large variety of a new class of catalysts for polyols oxidation with efficiency in terms of current densities and poisoning stability.