The modern fast electron and its application to understanding functional perovskite, semiconducting and plasmonic nanostructures

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1 2017 FACTS Seminars

2 The modern fast electron and its application to understanding functional perovskite, semiconducting and plasmonic nanostructures Date: 16 November, 10 am Location: MSE Meeting Room 1 (N ) Presenter: Prof Joanne Etheridge Monash Centre for Electron Microscopy Department of Materials Science and Engineering, Monash University, Australia Abstract: Recent advances in electron-optics have given us the ability to generate and manipulate highly stable, phase coherent electron wavefields that can be brought to a focal point much smaller than an atom. This is enabling the exploration of fundamental phenomena in quantum physics, electronoptics and electron-atom interactions. It is also being applied to probe the atomic and electronic structure of matter with unprecedented spatial and energy resolution. In particular, electron scattering experiments can now be performed from small numbers of important atoms selected from within a specimen, offering powerful capabilities for determining the local structure and bonding of nanostructured materials. This talk will give an overview of these developments, and will illustrate with various applications, including mapping surface plasmon polaritons in metallic nanostructures; revealing Li-dependent 3D octahedral superlattices in Li-ion conductors; determining the structure of photoactive organicinorganic-perovskites; characterising structure-property relationships in semiconducting nanostructures; understanding crystal growth and shape control in metal nanoparticles; and imaging the distribution of electrons as they scatter within an atomic lattice.

3 Quantitative high-resolution electron holography of two-dimensional transition metal dichalcogenides Date: Wednesday 15 November, 4-5 pm Location: MSE Meeting Room 1 (N ) Presenter: Prof Rafal Dunin-Borkowski Institute for Microstructure Research (Director) Ernst Ruska-Centre for Microscopy & Spectroscopy with Electrons RWTH Aachen University (Professor) Abstract: Off-axis electron holography is a powerful technique for recording the phase shift of a high-energy electron wave that has passed through an electron-transparent specimen in the transmission electron microscope. The phase shift is, in turn, sensitive to the electrostatic potential and magnetic induction in the specimen, projected in the electron beam direction. We are currently working on several model-based approaches that can be used to provide quantitative interpretations of phase images recorded using off-axis electron holography. In this talk, I will show how iterative fitting of specimen thickness, specimen tilt, absorption, image spread and electron optical aberrations can be performed by comparing experimental phase and amplitude images of twodimensional WSe2 with simulations on an absolute scale. The simulations are based on scattering potentials derived from density functional theory and include bonding effects, which are found to be necessary to achieve quantitative agreement between experimental and simulated phase images. By removing residual aberrations from the experimental phase and amplitude images and comparing them with simulations, a quantitative description of the atomic structure of the material, including the detection of changes in electrostatic potential associated with individual structural defects and dopant atoms, becomes possible.

4 Micromanipulator Live Demo Session Date / Time: 26 th Oct 2017, 1pm to 4pm Location: FACTS There will be a live demo session by Japan Micro Support Co. ltd on 26 th Oct for their micromanipulator. The micromanipulator is very useful for picking up very small sample up to a few micron in size. You may find it useful for your research. For more information on the demo schedule, please refer to the pdf.

5 "In operando TEM observations of solar cells and resistive switching memory devices; Visualizing correlations between electrical properties and the structural changes" Date: 6 April 2017, 10:00-11:00am Location: MSE Meeting Room 1 (N ) Presenter: Martial Duchamp Assistant Professor School of Materials Science and Engineering Abstract: Transmission electron microscopy (TEM) is typically regarded as a static observation technique. Recent hardware advancements, however, have facilitated TEM-based in operando studies lending nanometer scale insight into the performance of materials and devices under external stimuli. This talk will offer an introduction to high resolution imaging and spectroscopic capabilities of modern transmission electron microscopes, before presenting recent results of in operando studies of real devices. The audience will learn how visualization of diffusion and nucleation processes can provide greater understanding of device performance, with primary focus on perovskite solar cells and thin film resistive switching devices. Apparatus used for in situ and in operando observations will be introduced, and current and future capabilities for in operando TEM investigations at FACTS will be presented.

6 2016 FACTS Seminars

7 FACTS Seminar: "Applications and Recent Advancements In Aberration- Corrected TEM: A Sneak Peek Into The Future Of Advanced Microscopy at FACTS" Date / Time: 7 Dec. 2016, 10:00-12:00 Location: MSE Meeting Room (N ) Presenter: Dr. Chris Boothroyd (FACTS) (Please register for this seminar at the below link, event location can hold up to 40 pax for this seminar): Abstract The maximum achievable resolution of electron microscopes is not limited by the fundamental properties of electrons, but rather by intrinsic imperfections of their electron lenses, of which the most severe is spherical aberration. While methods to overcome aberrations have been known for many years, it is only recently that practical aberration correctors have been developed for the latest generation of transmission electron microscopes. In this talk, the speaker will describe on how aberration correctors work, present examples of some investigations made using aberration-corrected TEMs and introduce the new instruments which will be coming to FACTS in 2017.

8 FACTS Seminar: "Introduction to Small-Wide Angle X-ray Scattering" Date / Time: 29 Nov. 2016, 14:00-16:00 Location: MSE Meeting Room (N ) Presenter: Dr. Sandra Desvergne-Bléneau (Xenocs, France) (Please register for this seminar at the below link, event location can hold up to 40 pax for this seminar): Abstract Nanostructured materials hold major expectations for the progress of fundamental & applied research. Understanding their properties requires investigations on a large range of compositions or process combinations demanding characterization over broad length scales. Moreover, one route for new materials is based on a bottom up approach, i.e. self-assembly of complex materials. Being of significant interest for a wide range of applications, they still require control and better understanding of their morphology, both for fundamental studies and for routine quality controls. Small Angle X-ray Scattering (SAXS) is a powerful measuring method for investigating nanostructured materials, providing information in the range from 1 nm to beyond 150 nm such as nanoscale morphology, mesoscale phase identification or surface to volume ratio of internal structures as a few examples. The method requires little sample preparation, is nondestructive and unlike microscopy probes a large volume of the sample enabling a statistically meaningful result. The same technique can be applied to surface only in the so-called "grazing incidence geometry". It can be combined with Wide Angle X-ray Scattering (WAXS) to get information on the material crystalline structure. Different experimental conditions such as temperature, humidity and mechanical stress can also be applied enabling in-situ structural investigation over changing conditions.

9 Topas Workshop Date / Time: 25 November 2016, 9:00-17:00 Location: NTU, TR+15 (NS ) Trainer: Dr. Tony Wang (Bruker) This will be a 1-day hands-on workshop for experienced TOPAS users. For more info please donwload the attached agenda.

10 Topas Workshop Date / Time: 29 July 2016, 9:00-16:00 Location: MSE E-learning Studio (N4.1-B2-01) Trainer: Dr. Tony Wang (Bruker) In this 1-day hands-on workshop, you will get to know the latest updates in TOPAS V5 software, which include the various applications for TOPAS in structure determination, refinement & quantitative phase analysis. You will also have to opportunity to meet with other TOPAS Users, and get any of your questions answered by our Bruker X-Ray Applications team.

11 Sustainable Energy Materials Research at SSRL Date / Time: 16 June 2016, 10:00 Location: MSE Conference Room, N Speaker: Prof. Michael Toney (SSRL, USA) The development of a carbon free economy is probably the greatest challenge facing humanity inthe coming decades. This has spurred significant research aimed at developing carbonfreeenergy sources and distribution. Here, a significant requirement is the discovery and developmentof new inexpensive and Earth abundant (or sustainable) materials for these technologies. In thistalk, I will describe the X-ray based research at SSRL involving materials that can be used forsustainable energy generation, use, and storage. I will first give a broad overview of X-raycharacterization techniques and then give a few examples of characterization of sustainableenergy materials to illustrate the breath of our efforts.

12 29 th International Symposium on Polymer Analysis and Characterization (ISPAC 2016) Date: June 2016 Location: Nanyang Executive Centre, Nanyang Technological University, Singapore Conference Chairperson: A/P Yeng Ming Lam (MSE, NTU) The International Symposium for Polymer Analysis and Characterization (ISPAC 2016) is an annual conference which usually takes place in the US or Europe. This year ISPAC is coming to NTU hence this is a great opportunity to take part in this international conference! It will be held in NTU from June We have lined up a series of very exciting symposia and speakers for this conference and would like to encourage you, your research staff and students to participate strongly in this conference and share your exciting work with other researchers in this field. There will also be a full day of short courses that will benefit young researchers and people new to some of these characterisation techniques. Conference website: Polymer-Analysis-and-Characterization.aspx

13 Panalytical XRD Application Seminar Date / Time: 21 March 2016, 14:00-16:00 Location: MSE N Speaker: Dr. Marco Sommariva (Panalytical) In this seminar, invited guest speaker Dr Sommariva will share on the various advanced applications. These include thin films analysis, residual stress, texture analysis as well as challenging applications which are normally devoted to synchrotron facilities. For example Small-Angle X-ray Scattering and Pair Distribution Function of nanomaterials. Dr Sommariva will be covering these applications in relation to PANalytical's XRD diffractometers, so that you can better optimise your instrument.