Tuning the Product Selectivity toward the High Yield of Glyceric Acid in Pt−CeO2/CNT Electrocatalyzed Oxidation of Glycerol

Graphical Biomass conversion : Electro-oxidation of glycerol over the Pt/CNT catalyst suffers from the poor activity, low glyceric acid (GLYA) selectivity, and high cost of the noble metal. The incorporation of CeO 2 into Pt/CNT achieves much enhanced yield of GLYA with even half dosage of Pt. Electrocatalytic oxidation of glycerol is a highly efficient way for upgrading glycerol toward fine chemicals. Currently, electro-oxidation of glycerol into the high value-added C3 products remains a big challenge because of the poor catalytic activity, low selectivity, and high cost of the noble metal catalysts, especially in the alkaline medium. Here, we report that the Pt−CeO 2 /CNT (CNT=carbon nanotubes) catalyst remarkably promotes the conversion (86.5 % vs. 37.6 %) and recycling stability for glycerol electro-oxidation reaction, as compared with Pt/CNT. However, the improved catalytic activity of Pt−CeO 2 /CNT is accompanied by the further oxidation of C3 products including glyceric acid (GLYA). By tuning the product distribution by the ratio of CeO 2 and CNT, applied potential, and the Pt loading amount, the high selectivities of C3 products (95 %) and GLYA (59 %) are achieved together with the high glycerol conversion (86 %), leading to the impressive yields of C3 products (81 %) and GLYA (50 %). The unique contributions of CeO 2 includes not only the enhanced catalytic activity and recycling stability, but also the suppressed further oxidation of GLYA. Moreover, higher yield of GLYA is reached over Pt−CeO 2 /CNT even with half loading of Pt, as compared with Pt/CNT.