A PdCu nanoalloy catalyst for preferential CO oxidation in the presence of hydrogen

Abstract

Catalytic oxidation of carbon monoxide (CO) is one of the essential steps for several environment- and energy-related applications. Here, we report the synthesis of alloy PdCu nanoparticles supported on an Al₂O₃ support as a catalyst for effective removal of CO from H₂-rich flue gases. The alloy phase between Pd and Cu was formed by deposition of organometallic Pd- and Cu-precursors on the Al₂O₃ support followed by thermal reduction under H₂. The alloy PdCu nanoparticles (average size: 30 nm) are in a spherical shape and they are distributed in the range between 10 and 80 nm. The alloy PdCu catalyst showed improved CO oxidation performance both in the presence and absence of H₂ compared to that of the reference Pd catalyst. It is also inferred that the alloy PdCu catalyst showed an onset temperature (T_o) of 50 °C in the presence of H₂ compared to that of CO oxidation in the absence of H₂ (T_o = 100 °C). In addition, the alloy PdCu catalyst showed selective CO oxidation performance below a temperature range of 300 °C. Therefore, the formation of the Pd-based alloy structures may have potential as the preferential CO oxidation catalyst for the catalytic removal of CO from various flue gases.