Enhanced Methane Steam Reforming Over Ni/BaZrO3

Abstract Thin films of BaZrO 3 , 0.5- and 1.0-nm thick, were prepared on high-surface-area MgAl 2 O 4 (MAO) by Atomic Layer Deposition (ALD) and examined as supports for Ni catalysts in Methane Steam Reforming (MSR). Scanning Transmission Electron Microscopy (STEM) showed that the films were conformal with the MAO surface. X-Ray Diffraction (XRD) with Rietveld Analysis indicated that the 1.0-nm film had a perovskite structure. A catalyst with 1-wt% Ni on the BaZrO 3 /MAO support exhibited similarities to exsolution catalysts in that catalysts oxidized at 1073 K and reduced at only 773 K were nearly 4 orders of magnitude less active than catalysts oxidized and reduced at 1073 K. Rates on Ni/BaZrO 3 /MAO catalyst were higher than those on Ni/MAO and exhibited a significantly different activation energy. Because BaZrO 3 is a proton conductor, it is suggested that MSR rates on Ni/BaZrO 3 /MAO are enhanced by proton transfer at the Ni-perovskite interface. Graphical Abstract