Fig. 1
From: Active site localization of methane oxidation on Pt nanocrystals
Schematic of in situ Bragg coherent X-ray diffraction imaging (BCDI). The BCDI measurement scheme during methane catalytic oxidation illustrates the acquisition of (111) Bragg coherent diffraction patterns from the same Pt nanocrystal throughout. Slices through the Bragg coherent diffraction patterns are measured for Pt nanocrystals above the catalytic activation temperature in the presence of different gases. a After 36 min in H2, b 2.6 min, and c 36 min after the O2 insertion, d ~2.6 min, e 16 min, and f 36 min after CH4 was introduced. Under a 20% O2 gas flow, the diffraction pattern becomes distorted (b and c), and continue to evolve when CH4 is added. The distortion fades in f owing to completion of the methane catalytic oxidation process in 1% CH4
