Selective glucose oxidation to glucaric acid using bimetallic catalysts: Lattice expansion or electronic structure effect?

Our study presents a comprehensive approach for the selective oxidation of glucose to glucaric acid (GA) by heterogeneous catalysis. We have synthesized and characterized Au/ZrO2, AuCu/ZrO2 and AuPt/ZrO2 catalysts using X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and oxygen pulse chemisorption (OPS) techniques. Combining experimental observations with in-depth density functional theory (DFT) studies, we found that bimetallic catalysts form alloys, which exhibit different charac-teristics than monometallic counterparts for the given reaction. We performed batch reactions, varying tem-perature and oxygen pressure, and used the data to construct a predictive microkinetic model. As it turned out, AuPt/ZrO2 showed the highest selectivity, yielding 32% of GA at 100 degrees C and 30 barg O2. Our results provide valuable insights for the developing of efficient catalysts and point out the bottlenecks for the oxidation of glucose to GA.

Automated summary

Our study presents a comprehensive approach for the selective oxidation of glucose to glucaric acid (GA) by heterogeneous catalysis. We synthesized and characterized Au/ZrO2, AuCu/ZrO2, and AuPt/ZrO2 catalysts and found that bimetallic catalysts form alloys, which exhibit different characteristics than monometallic counterparts. We also constructed a predictive microkinetic model and found that AuPt/ZrO2 showed the highest selectivity. These results provide valuable insights for the developing of efficient catalysts and point out the bottlenecks for the oxidation of glucose to GA.