Carbon paper supported gold nanoflowers for tunable glycerol electrooxidation boosting efficient hydrogen evolution

Abstract

Thermodynamically favorable selective electrooxidation reactions coupled with hydrogen evolution reaction (HER) is a promising strategy for simultaneous production of value-added chemicals and hydrogen. In this work, a binder-free gold nanoflowers electrode based on carbon paper is prepared and used as anode catalyst, which results in good charge transfer, high stability and superior catalytic activity for electrooxidation of glycerol. We develop an integrated system of glycerol electrooxidation with HER, and the effect of potential on the distribution of anodic electrooxidation products and cathodic hydrogen production are investigated. At 1.0 V, the overall reaction reaches 10 mA cm−2 and the selectivity of glyceric acid (GLA) reaches 97.2%. At 1.2 V, hydrogen production reaches the highest value of 960 μmol L−1 and the anode product consists of a mixture of glyceric acid, glycolic acid (GA) and formic acid (FA). At 1.3 V, the selectivity of FA reaches 87.3%. Operando technique in situ infrared spectroscopy is used to monitor the immediate evolution and study the pathway of controlled glycerol electrooxidation. This work demonstrates carbon paper is a promising substrate material of binder-free electrode applied in thermodynamically favorable electrocatalytic reactions boosting hydrogen evolution.