title: Operando Nanobeam Diffraction to Follow the Decomposition of Individual Li2O2 Grains in a Nonaqueous Li-O2 Battery.
abstract: Intense interest in the Li-O2 battery system over the past 5 years has led to a much better understanding of the various chemical processes involved in the functioning of this battery system. However, detailed decomposition of the nanostructured Li2O2 product, held at least partially responsible for the limited reversibility and poor rate performance, is hard to measure operando under realistic electrochemical conditions. Here, we report operando nanobeam X-ray diffraction experiments that enable monitoring of the decomposition of individual Li2O2 grains in a working Li-O2 battery. Platelet-shaped crystallites with aspect ratios between 2.2 and 5.5 decompose preferentially via the more reactive (001) facets. The slow and concurrent decomposition of individual Li2O2 crystallites indicates that the Li2O2 decomposition rate limits the charge time of these Li-O2 batteries, highlighting the importance of using redox mediators in solution to charge Li-O2 batteries.
authors: Department of Radiation Science and Technology, Delft University of Technology , Mekelweg 15, 2629JB Delft, The Netherlands.
authors: Swapna
authors: S
authors: Ganapathy
authors: Department of Radiation Science and Technology, Delft University of Technology , Mekelweg 15, 2629JB Delft, The Netherlands.
authors: Jouke R
authors: JR
authors: Heringa
authors: Department of Radiation Science and Technology, Delft University of Technology , Mekelweg 15, 2629JB Delft, The Netherlands.
authors: Maria S
authors: MS
authors: Anastasaki
authors: Department of Chemistry and the Waterloo Institute for Nanotechnology, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada.
authors: Brian D
authors: BD
authors: Adams
authors: Department of Radiation Science and Technology, Delft University of Technology , Mekelweg 15, 2629JB Delft, The Netherlands.
authors: Martijn
authors: M
authors: van Hulzen
authors: Kavli Institute of Nanoscience Delft, Department of Quantum Nanoscience, Delft University of Technology , Lorentzweg 1, 2628CJ Delft, The Netherlands.
authors: Shibabrata
authors: S
authors: Basak
authors: Department of Radiation Science and Technology, Delft University of Technology , Mekelweg 15, 2629JB Delft, The Netherlands.
authors: Zhaolong
authors: Z
authors: Li
authors: European Synchrotron Radiation Facility , 6 rue Jules Horowitz, BP 220, 38043 Grenoble Cedex, France.
authors: Jonathan P
authors: JP
authors: Wright
authors: Department of Chemistry and the Waterloo Institute for Nanotechnology, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada.
authors: Linda F
authors: LF
authors: Nazar
authors: Department of Radiation Science and Technology, Delft University of Technology , Mekelweg 15, 2629JB Delft, The Netherlands.
authors: Niels H
authors: NH
authors: van Dijk
authors: Department of Radiation Science and Technology, Delft University of Technology , Mekelweg 15, 2629JB Delft, The Netherlands.
authors: Marnix
authors: M
authors: Wagemaker