By combining cyclic voltammetry and potentiostatic current transients with measurements of the potential dependence of gold’s reflectance at 520 nm, we provide unambiguous evidence that glycerol and gold oxidation compete for adsorbed OH, whereby the formation of gold oxide is retarded in the presence of glycerol and the formation of gold oxide inactivates the oxidation of glycerol. Potentiostatic current transients coupled with ATR-SEIRAS at potentials close to the onset of glycerol oxidation also suggest that the adsorption of carboxylates generated upon oxidation of glycerol leads to a progressive decrease of the electrocatalytic activity. However, both ATR-SEIRAS and experiments using a rotating-disk electrode suggest that the adsorption of these carboxylates is an equilibrium process. Therefore, using high flow rates should allow to keep the inhibition of the reaction at an acceptable level. These results are relevant for the design of fuel cells capable of generating electricity plus value-added chemicals from glycerol.

通过将循环伏安法和恒电位瞬变与金在520 nm处的反射率的电势依赖性进行测量相结合，我们提供了明确的证据，甘油和金的氧化作用与吸附的OH竞争，从而在甘油和三价铬存在下，氧化金的形成受到阻碍。氧化金的形成使甘油的氧化失活。电位稳定电流瞬变与ATR-SEIRAS的电位接近于甘油氧化的开始，也表明甘油氧化产生的羧酸盐的吸附会导致电催化活性的逐渐降低。但是，ATR-SEIRAS和使用转盘电极的实验均表明，这些羧酸盐的吸附是一个平衡过程。因此，使用高流速应使反应抑制保持在可接受的水平。这些结果与燃料电池的设计有关，该燃料电池能够发电，并由甘油制成增值化学品。