| Summary: | The effects of cell voltage and of concentration of sugars (glucose and xylose) on the performances of their electro-reforming have been evaluated at a Pd<sub>3</sub>Au<sub>7</sub>/C anode in 0.10 mol L<sup>−1</sup> NaOH solution. The catalyst synthesized by a wet chemistry route is first comprehensively characterized by physicochemical and electrochemical techniques. The supported catalyst consists in alloyed Pd<sub>3</sub>Au<sub>7</sub> nanoparticles of circa 6 nm mean diameter deposited on a Vulcan XC72 carbon support, with a metal loading close to 40 wt%. Six-hour chronoamperometry measurements are performed at 293 K in a 25 cm<sup>2</sup> electrolysis cell for the electro-conversion of 0.10 mol L<sup>−1</sup> and 0.50 mol L<sup>−1</sup> glucose and xylose at cell voltages of +0.4 V, +0.6 V and +0.8 V. Reaction products are analyzed every hour by high performance liquid chromatography. The main products are gluconate and xylonate for glucose and xylose electro-reforming, respectively, but the faradaic yield, the selectivity and the formation rate of gluconate/xylonate decrease with the increase of aldose concentration, whereas lower faradaic yields and higher formation rates of gluconate/xylonate are observed at +0.8 V than at +0.4 V (higher chemical yields).
|
|---|