Fig. 4: Surface chemistry of palladium clusters and nanoparticles during CH4 oxidation.
From: Anchoring PdOx clusters on defective alumina for improved catalytic methane oxidation
a Operando Fourier transform-infrared (FT-IR) spectra of Pd/Al2O3 (Pd NPs) and Pd/Al2O3-x (Pd clusters) at the steady states under reaction condition. CH4 : O2 : He = 2:8:90, reaction temperature = 400 °C, GHSV = 60,000 mL·gcat−1·h−1. In-situ FT-IR spectra of Pd/Al2O3 (b) and Pd/Al2O3-x (c) in the successive O2-to-CH4 and CH4-to-O2 switching processes, reaction temperature = 400 °C. Plots of the normalized integrated area of the IR absorption of each surface species on Pd/Al2O3 (d) and Pd/Al2O3-x (e) as a function of time during gas switching experiments.
