Adam HITCHCOCK
(Department of Chemistry & Chemical Biology, Brockhouse Institute for Materials Research, McMaster University, Hamilton, Canada)
Soft X-ray scanning transmission microscopy (STXM) [1,2] is a powerful tool for nanoscale materials analysis, with significant advantages over analytical X-ray microscopies for studies of radiation sensitive materials. Ptychography (scanning coherent diffraction imaging) [3], can be measured using soft X-ray STXMs. Significant improvements in spatial resolution can be achieved with ptychography (3-14 nm) relative to conventional STXM (15-30 nm). 4D imaging – quantitative chemical mapping in 3D by tilt angle tomography at multiple energies – can be performed with both STXM [4] and ptychography [5]. STXM and ptychography methods will be described, with emphasis on spectromicroscopy, the use of chemical mapping by imaging at many photon energies. Performance will be illustrated by recent 2D and 3D studies of cathodes of low temperature, proton exchange membrane fuel cell (PEM-FC) systems [6,7].
Research supported by AFCC, NSERC, Canada Research Chairs, and the Catalyst Research for Polymer Electrolyte Fuel Cells (CaRPE-FC) network. STXM is performed on BL 10ID1 at the Canadian Light Source (CLS), which is supported by NSERC,CIHR, NRC and U. Saskatchewan, and on BLs 5.3.2.2 & 11.0.2 at the Advanced Light Source (ALS). Ptychography is performed on BL 5.3.2.1 and 11.0.2 at the ALS. ALS is supported by Office of Basic Energy Science, Department of Energy. Ptychography processing is performed using SHARP, a program of the Center for Applied Mathematics for Energy Research Applications, LBNL.
I thank Soleil and the Hermes team for their hospitality during my research leave visit, Mar-Jun, 2018.
[1] A.P. Hitchcock, Soft X-ray Imaging and Spectromicroscopy in Handbook on Nanoscopy, eds. G. Van Tendeloo, D. Van Dyck and S. J. Pennycook (Wiley, 2012).
[2] A.P. Hitchcock, J. Electron Spectrosc. Rel. Phen. 200 (2015) 49.
[3] D.A. Shapiro et al., Nature Photonics. 8 (2014) 765.
[4] G. Schmid, et al, Characterization Tools for Nanoscience & Nanotechnology 5 (2016) 43.
[5] Yu Y, et al. Nature Communications 9 (2018) 921.
[6] A. Putz et al. ECS Transactions 75 (2016) 3.
[7] J. Wu et al J. Power Sources 381 (2018) 72.
Formalités d’entrée :
Accès libre dans l’amphi du pavillon d’Accueil.
Si la manifestation a lieu dans le Grand Amphi SOLEIL du Bâtiment Central merci de vous munir d’une pièce d’identité (à échanger à l’accueil contre un badge d’accès)
Contact : Sandrine Vasseur
Documents à télécharger
sem-180608-hitchcock.pdf (251.56 Ko - pdf) (251.56 Ko)