Fig. 1: Characterization of fresh catalysts.
From: Dynamic behavior of molecular Pd-acetate trimers and dimers in heterogeneous vinyl acetate synthesis
a, b Pd K edge XANES(a) and EXAFS (b) for the PdOAc/SiO2 (solid red) and PdOAc/KOAc/SiO2 (solid blue) fresh catalysts and the Pd foil (dashed black), PdO (dashed green), and Pd(acac)2 (dashed orange) reference materials. c, d Deconvoluted DRIFTS spectra in the 2000 – 1100 cm−1 acetate region of the fresh PdOAc/SiO2 (c) and PdOAc/KOAc/SiO2 (d) catalysts. A KOAc-free PdCl2/SiO2 sample was used as background for spectra in (c, d). Species present in (c, d) include K2Pd2(OAc)6 dimer (orange, 1640 cm−1), Pd3(OAc)6 trimer (purple, 1610 cm−1), KOAc (green, 1580 cm−1), Pd2(OAc)4 dimer (pink, 1570 cm−1), and bridged silyl acetate (gold, 1545 cm−1). Analysis conditions for experiments in (c, d): 1 atm; 25 °C; and 50 sccm; 100 vol% He.
