title: Nanoscale Chemical Imaging of an Individual Catalyst Particle with Soft X-ray Ptychography.
abstract: Understanding Fe deposition in fluid catalytic cracking (FCC) catalysis is critical for the mitigation of catalyst degradation. Here we employ soft X-ray ptychography to determine at the nanoscale the distribution and chemical state of Fe in an aged FCC catalyst particle. We show that both particle swelling due to colloidal Fe deposition and Fe penetration into the matrix as a result of precracking of large organic molecules occur. The application of ptychography allowed us to provide direct visual evidence for these two distinct Fe-based deactivation mechanisms, which have so far been proposed only on the basis of indirect evidence.
authors.affiliation: Stanford Synchrotron Radiation Lightsource, Stanford University , Menlo Park, California 94025, United States.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Wise
authors.affiliation: Stanford Synchrotron Radiation Lightsource, Stanford University , Menlo Park, California 94025, United States.
authors.forename: Johanna Nelson
authors.initials: JN
authors.lastname: Weker
authors.affiliation: Inorganic Chemistry and Catalysis group, Debye Institute for Nanomaterials Science, Utrecht University , 3584 CG Utrecht, The Netherlands.
authors.forename: Sam
authors.initials: S
authors.lastname: Kalirai
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: Maryam
authors.initials: M
authors.lastname: Farmand
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: David A
authors.initials: DA
authors.lastname: Shapiro
authors.affiliation: Inorganic Chemistry and Catalysis group, Debye Institute for Nanomaterials Science, Utrecht University , 3584 CG Utrecht, The Netherlands.
authors.forename: Florian
authors.initials: F
authors.lastname: Meirer
authors.affiliation: Inorganic Chemistry and Catalysis group, Debye Institute for Nanomaterials Science, Utrecht University , 3584 CG Utrecht, The Netherlands.
authors.forename: Bert M
authors.initials: BM
authors.lastname: Weckhuysen
keywords: catalyst deactivation; chemical imaging; fluid catalytic cracking; iron and soft X-ray ptychography