ZnCo2O4 supported low-loading Pd as an enhanced catalyst for low temperature oxidation of carbon monoxide

Abstract

We have successfully synthesized a series of Pd/ZnCo2O4 supported catalytic materials with low noble metal loading and high activity by the impregnation method. The Pd/ZnCo2O4 catalysts containing 0.2% Pd have superior performance for oxidizing CO at 80 °C, achieving 100% conversion. There is also no loss of activity after four cycles of tests, with the conversion remaining approximately 100%. Aside from that, various advanced physicochemical characterizations indicate that this excellent catalytic performance stems from the interaction between metal Pd and carrier ZnCo2O4. Pd provides a higher degree of accessibility to the active site, while ZnCo2O4 as a carrier can better stabilize Pd nanoparticles. The 0.2% Pd/ZnCo2O4 exhibits higher levels of Pd2+ species as the electronic interaction between Pd and ZnCo2O4 improves, thus improving CO oxidation catalytic efficiency. Furthermore, the low loading of Pd is crucial for reducing the cost of noble metal catalysts and ameliorating their practicality in industrial applications.